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ABCB Reference Document AUTOMATIC FIRE SPRINKLER SYSTEMS September 2008 This document includes material (including illustrations) based on Australian Standards AS 2118.1- 1999 and AS 2118 - 2006. The copyright owner, Standards Australia Limited, has consented to the reproduction of that material in this document for the purpose of allowing it to be issued for public review. However, Standards Australia Limited does not accept responsibility for the technical content of this public review document.

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Page 1: Fire Sprinkler - ABCB Reference Document - Automatice Fire Sprinkler System

ABCB Reference Document

AUTOMATIC FIRE SPRINKLER SYSTEMS

September 2008

This document includes material (including illustrations) based on Australian Standards AS 2118.1-1999 and AS 2118 - 2006. The copyright owner, Standards Australia Limited, has consented to the reproduction of that material in this document for the purpose of allowing it to be issued for public review. However, Standards Australia Limited does not accept responsibility for the technical content of this public review document.

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PREFACE This reference document was prepared by the Australian Building Codes Board. The document has been prepared in consideration of the content of AS2118.1 (2006) ‘Automatic Fire Sprinkler Systems’ with modifications as necessary to render it suitable for adoption within the Building Code of Australia (BCA).

The document includes changes to AS2118 (1999) that reflect advances in technology and also refines the content of AS2118 (1999) for clarity and conciseness.

The document also reflects the ABCB objective to include all public policy matters within the BCA.

Changes to Sections 1 and 2

(a) Preface and Foreword amended to reflect the goals of the BCA

(b) Revised ‘Scope’ to reflect the requirements of the ABCB

(c) New definitions added for the terms ‘Appropriate Authority’, ‘Building Solution’ and ‘Required Duration’ and an amended definition for ‘Design Area’,

(d) General classifications of systems have been relocated to the BCA

(e) Required duration times have been relocated to the BCA

Changes to Sections 3, 5, 6, 8, 10 and 12

(a) Various editorial changes for consistency with the BCA

(b) Certain requirements for the operation of alarms have been relocated to the BCA

(c) Required duration times have been relocated to the BCA

(d) Permitted exceptions in Section 3 have been reduced to reflect safety and compatibility issues.

(e) Tables for sprinkler clearances in Section 5 have been expanded to include Light Hazard spray sprinklers.

(f) Concealed space protection has been revised to take into account potential changes during the life of the building.

(g) Requirements for systems interface alarm signals have been added to Section 8 to align with current practice.

(h) The design process for ordinary hazard in Section 10 has been simplified to align with the previously adopted approach in Section 9 particularly in regard to the number of sprinklers in operation.

(i) The principles for calculations in Section 12 remain unchanged; however, the determination of the design area has been simplified. An appendix has been provided to assist the designer with hydraulic calculations in preparing the graphical representation of supply and demand curves and includes worked examples.

Changes to Section 4

The restructured Section 4 discards the principle of graded water supplies. Instead, it accepts a single town main supply meeting prescribed criteria, including the capability of simultaneously supplying specified hydrant flows, as the benchmark ‘reliable supply’.

Other acceptable sources of water supply are selected to equate to this reliability benchmark. For example, when a town main supply requires boosting by automatic pumps in order to meet the specified flow and pressure demand, two parallel-connected full capacity pumps are required, one electric motor-driven and the other diesel engine-driven.

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Where a higher degree of water supply reliability is required (in the case, for example, of a high-rise apartment building), Section 4 introduces the concept of ‘dual’ water supplies. ‘Dual’ water supplies are not ‘duplicate’ supplies, but are considered to be more reliable than single supplies. This is illustrated in the case of pump suction tanks which, as single supplies, may be 2/3 capacity (if provided with adequate automatic inflow) and supply two automatic full capacity pumps, one electric motor-driven and the other diesel engine-driven.

The corresponding dual water supply arrangement would involve two-pump suction tanks (each 2/3 capacity and not requiring automatic inflow) supplying two automatic full capacity pumps, one electric motor-driven and the other diesel engine-driven.

Changes to Sections 7 and 13

AS 2118.8, AS 2118.9 and AS 2118.10 have been included in this Standard, consistent with consolidating the AS 2118 sprinkler suite of Standards.

Section 14

Consistent with the elements comprising design, installation and commissioning of automatic fire sprinkler systems, Section 14 addresses commissioning and acceptance testing of sprinklers and covers the hydrostatic pressure test, pre-test equipment checks, equipment tests and water supply tests. Personnel involved in the commissioning process have a commissioning check list to follow to ensure that, when complete, the system is ready for operation.

Appendices A and B have been deleted in accordance with the ABCB Protocol for Development of Reference Documents

Appendix C ‘Graphic representation of hydraulic characteristics’ is new and should be of assistance when interpreting the requirements of Sections 4 and 12.

Appendix D has been deleted

The suite of sprinkler installation systems and components, when completed, will incorporate the current AS 4118 series and will comprise two sets, all within the AS 2118 designation, as follows:

AS 2118 Automatic fire sprinkler—Systems Part 1: General systems requirements Part 2: Drenchers Part 3: Deluge Part 4: Residential Part 5: Home (Supersedes ‘Domestic’) Part 6: Combined sprinklers and hydrants

AS 4118 Automatic fire sprinkler—Components Part 1.1: Sprinklers and sprayers Part 1.2: Alarm valves (wet) Part 1.3: Water motor alarms Part 1.4: Valve monitors Part 1.5: Deluge and pre-action valves Part 1.6: Stop valves and non-return valves Part 1.7: Alarm valves (dry) Part 1.8: Pressure reducing valves Part 2.1: Piping—General

The terms ‘normative’ and ‘informative’ have been used in this Standard to define the application of the appendix to which they apply. A ‘normative’ appendix is an integral part of a Standard, whereas an ‘informative’ appendix is only for information and guidance.

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This Standard incorporates commentary on some of the clauses. The commentary directly follows the relevant clause, is designated by ‘C’ preceding the clause number and is printed in italics in a panel. The commentary is for information only and does not need to be followed for compliance with the Standard.

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CONTENTS

PREFACE 2

FOREWORD 14

SECTION 1 SCOPE AND GENERAL 15

1.1 SCOPE................................................................................................................................ 15

1.2 REFERENCED DOCUMENTS.......................................................................................... 15

1.3 DEFINITIONS ................................................................................................................... 16 1.3.1 Alarm signalling equipment (ASE) ............................................................................... 16 1.3.2 Alarm valve................................................................................................................... 16 1.3.3 Appropriate Authority ................................................................................................... 16 1.3.4 Automatic inflow........................................................................................................... 16 1.3.5 Building owner.............................................................................................................. 16 1.3.6 Building Solution .......................................................................................................... 16 1.3.7 Compartment................................................................................................................. 16 1.3.8 Design area.................................................................................................................... 17 1.3.9 Design density ............................................................................................................... 17 1.3.10 Designated building entry point (DBEP) ..................................................................... 17 1.3.11 Designated site entry point (DSEP) ............................................................................. 17 1.3.12 Effective height ........................................................................................................... 17 1.3.13 Fire and draft stop ....................................................................................................... 17 1.3.14 High-rise ..................................................................................................................... 17 1.3.15 Installation................................................................................................................... 17 1.3.16 K factor (nominal) ....................................................................................................... 17 1.3.17 Listed .......................................................................................................................... 18 1.3.18 Maximum flow rate of the system (Qmax.) .................................................................... 18 1.3.19 Monitoring centre ........................................................................................................ 18 1.3.20 Multiple controls ......................................................................................................... 18 1.3.21 Multistorey .................................................................................................................. 18 1.3.22 Net positive suction head (NPSH) ............................................................................... 18 1.3.23 Open joists and exposed common rafters..................................................................... 18 1.3.24 Post or box pallet......................................................................................................... 18 1.3.25 Required duration of operation .................................................................................... 18 1.3.26 Special sprinkler .......................................................................................................... 18 1.3.27 Special sprinkler system .............................................................................................. 19 1.3.28 Sprayer ........................................................................................................................ 19 1.3.29 Sprinkler-protected building........................................................................................ 20 1.3.30 Sprinkler system.......................................................................................................... 20 1.3.31 Standard sprinkler........................................................................................................ 20 1.3.32 Standard sprinkler system............................................................................................ 22 1.3.33 Thermal sensitivity ...................................................................................................... 22

SECTION 2 SPRINKLER SYSTEM DESIGN DATA 23

2.1 TYPES OF SPRINKLER SYSTEMS AND AREA LIMITATIONS .................................. 23 2.1.1 General .......................................................................................................................... 23 2.1.2 Standard sprinkler system.............................................................................................. 23 2.1.3 Special sprinkler systems............................................................................................... 27

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2.1.4 Sprinkler compatibility .................................................................................................. 29

SECTION 3 EXTENT OF PROTECTION AND SYSTEM MONITORING 30

3.1 PROTECTION AGAINST EXPOSURE HAZARDS ......................................................... 30 3.1.1 General .......................................................................................................................... 30 3.1.2 Sprinklers ...................................................................................................................... 30 3.1.3 Shielding ....................................................................................................................... 30 3.1.4 Sprinkler spacing and location....................................................................................... 30 3.1.5 Piping ............................................................................................................................ 35 3.1.6 Performance .................................................................................................................. 35 3.1.7 Water supply ................................................................................................................. 35

3.2 ALARM SIGNALLING ..................................................................................................... 35 3.2.1 General .......................................................................................................................... 35 3.2.2 Integrity and marking requirements—Electrical wiring................................................. 35

3.3 SYSTEM COMPONENT FAULT MONITORING............................................................ 35 3.3.1 General .......................................................................................................................... 35 3.3.2 Fault monitoring devices ............................................................................................... 35 3.3.3 Systems to be monitored................................................................................................ 36 3.3.4 Components to be monitored......................................................................................... 36 3.3.5 Installation..................................................................................................................... 36

SECTION 4 WATER SUPPLIES 37

4.1 SUPPLY ............................................................................................................................. 37 4.1.1 General .......................................................................................................................... 37 4.1.2 Reliable water supply .................................................................................................... 37 4.1.3 Acceptable sources of water supply............................................................................... 37

4.2 DUAL WATER SUPPLIES................................................................................................ 37 4.2.1 General .......................................................................................................................... 37 4.2.2 Acceptable arrangements............................................................................................... 38

4.3 GENERAL WATER SUPPLY PROVISIONS.................................................................... 40 4.3.1 General .......................................................................................................................... 40 4.3.2 Town main water supply ............................................................................................... 40 4.3.3 Private system water supply .......................................................................................... 41 4.3.4 Pump suction tank water supply .................................................................................... 42 4.3.5 Supply from natural source............................................................................................ 45 4.3.6 Gravity tank water supply.............................................................................................. 48 4.3.7 Pressure tank water supply ............................................................................................ 49 4.3.8 Pump system design and installation ............................................................................. 50 4.3.9 Pumpsets ....................................................................................................................... 54

4.4 PROVING OF WATER SUPPLIES ................................................................................... 55

4.5 CONNECTIONS FOR OTHER SERVICES....................................................................... 55 4.5.1 General .......................................................................................................................... 55 4.5.2 Combined sprinkler and hydrant water supply............................................................... 55 4.5.3 Fire hose reel connections ............................................................................................. 56 4.5.4 Fire brigade booster connection..................................................................................... 57

SECTION 5 SPACING AND LOCATION OF SPRINKLERS 58

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5.1 SPACING OF SPRINKLERS............................................................................................. 58 5.1.1 Standard sprinkler spacing............................................................................................. 58 5.1.2 Special sprinkler spacing ............................................................................................... 58 5.1.3 Staggered spacing.......................................................................................................... 58

5.2 MINIMUM DISTANCE BETWEEN SPRINKLERS ......................................................... 58

5.3 LOCATION OF SPRINKLERS (OTHER THAN SIDEWALL SPRINKLERS) ................ 58 5.3.1 General .......................................................................................................................... 58 5.3.2 Walls and partitions....................................................................................................... 58 5.3.3 Ceilings, roofs and underside of stairs ........................................................................... 60

5.4 SPACING AND LOCATION OF SIDEWALL SPRINKLERS.......................................... 61 5.4.1 General .......................................................................................................................... 61 5.4.2 Spacing of special sidewall sprinklers ........................................................................... 61 5.4.3 Maximum spacing of sidewall sprinklers ...................................................................... 61 5.4.4 Distance between rows of sprinklers ............................................................................. 61

5.5 OBSTRUCTIONS TO SPRINKLER DISCHARGE........................................................... 61 5.5.1 General .......................................................................................................................... 61 5.5.2 Standard upright and pendent sprinklers........................................................................ 61 5.5.3 Standard sidewall sprinklers .......................................................................................... 63 5.5.4 Standard upright and pendent sprinklers near columns.................................................. 65 5.5.5 Standard sidewall sprinklers near columns .................................................................... 66 5.5.6 Roof trusses................................................................................................................... 66 5.5.7 Clear space below sprinklers ......................................................................................... 67 5.5.8 Obstructions in clear space ............................................................................................ 67 5.5.9 Obstructions under sprinklers ........................................................................................ 67

5.6 CONCEALED SPACES..................................................................................................... 68 5.6.1 General .......................................................................................................................... 68 5.6.2 Protection criteria .......................................................................................................... 69 5.6.3 Hydraulic design—concealed spaces............................................................................. 69 5.6.4 Deformable ceilings ...................................................................................................... 69

5.7 SPECIAL CONSIDERATIONS (SUPPLEMENTARY PROTECTION) FOR REQUIRED SPRINKLER SYSTEMS. ......................................................................................................... 69

5.7.1 Machinery pits and production lines.............................................................................. 69 5.7.2 Hoists, lift shafts, building services shafts and enclosed chutes..................................... 69 5.7.3 Elevators, rope or strap races, exhaust ducts, gearing boxes and dust receivers............. 70 5.7.4 Corn, rice, provender and oil mills ................................................................................ 70 5.7.5 Bins and silos ................................................................................................................ 71 5.7.6 Escalators ...................................................................................................................... 71 5.7.7 Canopies........................................................................................................................ 71 5.7.8 Roof overhang ............................................................................................................... 71 5.7.9 Exterior docks and platforms......................................................................................... 71 5.7.10 Covered balconies ....................................................................................................... 71 5.7.11 Enclosed paint lines, drying ovens, drying enclosures ................................................. 71 5.7.12 Spray booths................................................................................................................ 72 5.7.13 Oil and flammable liquid hazards ................................................................................ 72 5.7.14 Commercial type cooking equipment and associated ventilation systems.................... 72 5.7.15 Air-handling plant ....................................................................................................... 75 5.7.16 Computer and other electronic equipment areas .......................................................... 75 5.7.17 Cupboards and wardrobes............................................................................................ 75 5.7.18 Film and television production studios ........................................................................ 75

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5.7.19 Theatres and music halls (protection on the stage side of the proscenium wall) .......... 75 5.7.20 Cold chambers............................................................................................................. 76

SECTION 6 SPRINKLERS, SPRAYERS AND MULTIPLE CONTROLS 78

6.1 GENERAL.......................................................................................................................... 78

6.2 TYPES OF SPRINKLERS, SPRAYERS AND MULTIPLE CONTROLS ......................... 78 6.2.1 Standard sprinklers ........................................................................................................ 78 6.2.2 Special sprinklers .......................................................................................................... 78 6.2.3 Sprayers......................................................................................................................... 78 6.2.4 Multiple controls ........................................................................................................... 79

6.3 HYDRAULIC CHARACTERISTICS OF STANDARD SPRINKLERS ............................ 79

6.4 APPLICATION OF SPRINKLER TYPES ......................................................................... 79

6.5 TEMPERATURE RATINGS.............................................................................................. 80

6.6 COLOUR CODING............................................................................................................ 80

6.7 ANTI-CORROSION TREATMENT OF SPRINKLERS .................................................... 80

6.8 SPRINKLER GUARDS...................................................................................................... 80

6.9 ESCUTCHEON PLATE ASSEMBLIES ............................................................................ 80

6.10 PROTECTION AGAINST FROST .................................................................................. 81

SECTION 7 PIPING 82

7.1 PIPE AND PIPE FITTINGS ............................................................................................... 82

7.2 HYDRAULIC TEST PRESSURE ...................................................................................... 82

7.3 PIPING IN NON-SPRINKLER-PROTECTED BUILDINGS............................................. 82

7.4 DRAINAGE ....................................................................................................................... 82 7.4.1 Wet system piping ......................................................................................................... 82 7.4.2 Dry or alternate wet and dry system piping ................................................................... 82

7.5 FLEXIBLE TUBE ASSEMBLIES ..................................................................................... 82

7.6 ORIFICE PLATES ............................................................................................................. 83

7.7 SUPPORT OF SPRINKLER PIPING ................................................................................. 83 7.7.1 General .......................................................................................................................... 83 7.7.2 Design ........................................................................................................................... 83 7.7.3 Corrosion protection of pipe supports............................................................................ 83 7.7.4 Requirements for pipe support components (see Figures 7.7.8.1(A) and (B))................ 84 7.7.5 Fixing of pipe supports.................................................................................................. 85 7.7.6 Spacing of supports ....................................................................................................... 86 7.7.7 Location of supports ...................................................................................................... 87 7.7.8 Verification of design .................................................................................................... 88

7.8 INSTALLATION—GENERAL ......................................................................................... 91

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7.8.1 Pipe and pipe fitting specifications ................................................................................ 91 7.8.2 Welding of piping.......................................................................................................... 92 7.8.3 Hydrostatic pressure test................................................................................................ 92 7.8.4 Pneumatic leak test ........................................................................................................ 92 7.8.5 Embedding of piping ..................................................................................................... 92 7.8.6 Corrosion protection of piping....................................................................................... 92 7.8.7 Protection of piping against mechanical damage ........................................................... 92 7.8.8 Facilities for flushing piping.......................................................................................... 92 7.8.9 Prohibited use of piping................................................................................................. 92 7.8.10 Pipe sizes..................................................................................................................... 93 7.8.11 Spacing of brackets and clips ...................................................................................... 93

7.9 INSTALLATION—STEEL PIPING .................................................................................. 93 7.9.1 Pipe and pipe fitting specifications ................................................................................ 93 7.9.2 Pipes.............................................................................................................................. 93 7.9.3 Pipe jointing .................................................................................................................. 93

7.10 INSTALLATION—LIGHT WALL STEEL PIPING........................................................ 94 7.10.1 Pipe and pipe fitting specifications .............................................................................. 94 7.10.2 Pipes............................................................................................................................ 94 7.10.3 Pipe jointing ................................................................................................................ 94

7.11 INSTALLATION—COPPER PIPING ............................................................................. 94 7.11.1 General ........................................................................................................................ 94 7.11.2 Pipes............................................................................................................................ 94 7.11.3 Pipe jointing ................................................................................................................ 95 7.11.4 Pipe bending................................................................................................................ 95

7.12 INSTALLATION—PLASTIC PIPING ............................................................................ 95 7.12.1 Pipe and pipe fitting specifications .............................................................................. 95 7.12.2 Pipe and fittings—Jointing .......................................................................................... 96 7.12.3 Corrosion protection of piping..................................................................................... 96

SECTION 8 VALVES AND ANCILLARY EQUIPMENT 97

8.1 CONTROL ASSEMBLIES................................................................................................. 97 8.1.1 General .......................................................................................................................... 97 8.1.2 Designated site and building entry points ...................................................................... 97

8.2 STOP VALVES.................................................................................................................. 97 8.2.1 General .......................................................................................................................... 97 8.2.2 Main stop valves............................................................................................................ 98 8.2.3 Stop valves controlling water supplies........................................................................... 98 8.2.4 Subsidiary stop valves ................................................................................................... 98

8.3 BLOCK PLAN ................................................................................................................... 98

8.4 ‘SPRINKLER STOP VALVE INSIDE’ PLATE................................................................. 99

8.5 EMERGENCY INSTRUCTIONS..................................................................................... 100

8.6 PRESSURE GAUGE SCHEDULE................................................................................... 100

8.7 SYSTEM INTERFACE DIAGRAM................................................................................. 102

8.8 STOP, DRAIN AND TEST VALVES, AND ALARM COCKS....................................... 102

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8.9 NON-RETURN (BACK-PRESSURE) VALVES ............................................................. 102

8.10 ALARM VALVES ......................................................................................................... 103 8.10.1 Wet............................................................................................................................ 103 8.10.2 Dry ............................................................................................................................ 103 8.10.3 Composite alarm valves............................................................................................. 103 8.10.4 Accelerators or exhausters for alarm valves (dry system).......................................... 103 8.10.5 Identification of control assemblies and water motor alarms ..................................... 103

8.11 PRESSURE-REDUCING VALVE STATIONS ............................................................. 103

8.12 DELUGE AND PRE-ACTION VALVES ...................................................................... 104 8.12.1 Deluge valves ............................................................................................................ 104 8.12.2 Pre-action valves ....................................................................................................... 104

8.13 ALARM DEVICES ........................................................................................................ 104 8.13.1 General ...................................................................................................................... 104 8.13.2 Prevention of false alarms ......................................................................................... 104 8.13.3 Water motor alarms ................................................................................................... 105 8.13.4 Fire alarm signal........................................................................................................ 106 8.13.5 System interface alarm signal .................................................................................... 106 8.13.6 Lock-open valve ........................................................................................................ 106 8.13.7 Testing of alarm devices............................................................................................ 106

8.14 REMOTE TEST VALVES ............................................................................................. 106

8.15 PRESSURE GAUGES.................................................................................................... 107

SECTION 9 LIGHT HAZARD CLASS SYSTEMS 109

9.1 GENERAL........................................................................................................................ 109

9.2 DESIGN DATA................................................................................................................ 109

9.3 WATER SUPPLY ............................................................................................................ 109 9.3.1 Flow and pressure requirements .................................................................................. 109 9.3.2 Water storage capacity ................................................................................................ 109 9.3.3 Additional storage capacity ......................................................................................... 110 9.3.4 Pump suction tanks...................................................................................................... 110 9.3.5 Pressure tanks.............................................................................................................. 110 9.3.6 Pumpsets ..................................................................................................................... 110 9.3.7 Proving of water supplies ............................................................................................ 110

9.4 SPRINKLERS .................................................................................................................. 110 9.4.1 Size and type ............................................................................................................... 110 9.4.2 Maximum area coverage per sprinkler......................................................................... 110 9.4.3 Reduced coverage........................................................................................................ 110 9.4.4 Maximum spacing ....................................................................................................... 111 9.4.5 Special sprinklers ........................................................................................................ 111

9.5 PIPING ............................................................................................................................. 111 9.5.1 Pipe types .................................................................................................................... 111 9.5.2 Pipe sizes..................................................................................................................... 111 9.5.3 Hydraulic calculations ................................................................................................. 111 9.5.4 Concealed spaces......................................................................................................... 111

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SECTION 10 ORDINARY HAZARD CLASS SYSTEMS 112

10.1 GENERAL...................................................................................................................... 112

10.2 DESIGN DATA.............................................................................................................. 112 10.2.1 General ...................................................................................................................... 112 10.2.2 Sprinklers under flat roofs and ceilings ..................................................................... 112 10.2.3 Sprinklers under sloping roofs and in bays ................................................................ 112

10.3 WATER SUPPLY .......................................................................................................... 113 10.3.1 Flow and pressure requirements ................................................................................ 113 10.3.2 Water storage capacity .............................................................................................. 113 10.3.3 Additional storage capacity ....................................................................................... 113 10.3.4 Pump suction tanks.................................................................................................... 113 10.3.5 Pressure tanks............................................................................................................ 114 10.3.6 Pumpsets ................................................................................................................... 114 10.3.7 Proving of water supplies .......................................................................................... 114

10.4 SPRINKLERS ................................................................................................................ 114 10.4.1 Size and type ............................................................................................................. 114 10.4.2 Maximum area coverage per sprinkler....................................................................... 114 10.4.3 Reduced coverage...................................................................................................... 114 10.4.4 Maximum spacing ..................................................................................................... 114 10.4.5 Maximum distance from walls and partitions (see also Clause 5.3.2) ........................ 115 10.4.6 Special sprinklers ...................................................................................................... 115

10.5 PIPING ........................................................................................................................... 115 10.5.1 Pipe types .................................................................................................................. 115 10.5.2 Pipe sizes................................................................................................................... 115 10.5.3 Hydraulic calculations ............................................................................................... 115 10.5.4 Concealed spaces....................................................................................................... 115

SECTION 11 HIGH HAZARD CLASS SYSTEMS 116

11.1 DESIGN DATA.............................................................................................................. 116 11.1.1 General ...................................................................................................................... 116 11.1.2 Process risks .............................................................................................................. 116 11.1.3 High piled storage risks ............................................................................................. 116 11.1.4 Type of system .......................................................................................................... 122

11.2 WATER SUPPLIES ....................................................................................................... 127 11.2.1 Pressure and flow requirements ................................................................................. 127 11.2.2 Minimum capacity of water supplies ......................................................................... 128 11.2.3 Pumps........................................................................................................................ 130 11.2.4 Proving of water supplies .......................................................................................... 130

11.3 SPACING OF STANDARD SPRINKLERS................................................................... 130 11.3.1 Maximum area coverage per sprinkler....................................................................... 130 11.3.2 Maximum distance between sprinklers on range pipes and between adjacent rows of

sprinklers ................................................................................................................. 130 11.3.3 Maximum distance from walls and partitions ............................................................ 130

11.4 SYSTEM COMPONENTS ............................................................................................. 130 11.4.1 Sprinklers .................................................................................................................. 130 11.4.2 Piping ........................................................................................................................ 131

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SECTION 12 HYDRAULIC CALCULATION OF SPRINKLER SYSTEMS 140

12.1 GENERAL...................................................................................................................... 140

12.2 DESIGN AREAS (ASSUMED AREAS OF OPERATION) ........................................... 140

12.3 SPRINKLERS IN SIMULTANEOUS OPERATION ..................................................... 141

12.4 SPRINKLER DISCHARGE FLOW RATES .................................................................. 141 12.4.1 Light Hazard and Ordinary Hazard class systems...................................................... 141 12.4.2 High Hazard class systems ........................................................................................ 141

12.5 POSITION OF DESIGN AREAS ................................................................................... 142 12.5.1 Hydraulically most unfavourable areas of operation.................................................. 142 12.5.2 Hydraulically most favourable areas of operation .................................................. 147

12.6 SHAPE OF DESIGN AREAS......................................................................................... 147 12.6.1 Hydraulically most unfavourable areas of operation.................................................. 147 12.6.2 Hydraulically most favourable areas of operation...................................................... 148

12.7 SUPPLY-DEMAND GRAPH......................................................................................... 149 12.7.1 General ...................................................................................................................... 149 12.7.2 Supply characteristics ................................................................................................ 149 12.7.3 Demand characteristics.............................................................................................. 149

12.8 WATER SUPPLIES ....................................................................................................... 150

12.9 PUMPSETS .................................................................................................................... 150 12.9.1 General ...................................................................................................................... 150 12.9.2 Maximum flow rate of the system (Qmax.) .................................................................. 150

12.10 CALCULATION OF PRESSURE LOSS IN PIPES ..................................................... 150

12.11 PRESSURE LOSSES.................................................................................................... 153 12.11.1 Fittings and valves................................................................................................... 153 12.11.2 Dry pendent (or upright) sprinklers ......................................................................... 153

12.12 ACCURACY OF CALCULATIONS............................................................................ 153

12.13 MINIMUM SPRINKLER DISCHARGE PRESSURE (HIGH HAZARD ONLY)........ 153

12.14 MINIMUM PIPE SIZES............................................................................................... 154

12.15 VELOCITY LIMITATION .......................................................................................... 154

12.16 VELOCITY PRESSURE .............................................................................................. 154

12.17 IDENTIFICATION OF FULLY HYDRAULICALLY CALCULATED SYSTEMS............. 154

APPENDIX A ORIFICE PLATES 156

A1 GENERAL...................................................................................................................... 156

A2 REQUIREMENTS.......................................................................................................... 156

A3 NOTES ON THE USE OF TABLES A1 AND A2 ......................................................... 156

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APPENDIX B WATER SUPPLY ARRANGEMENTS 159

APPENDIX C GRAPHIC REPRESENTATION OF HYDRAULIC CHARACTERISTICS 163

C1 GENERAL...................................................................................................................... 163

C2 THE SUPPLY-DEMAND GRAPH................................................................................. 163

C3 STATIC PRESSURE AND DEMAND CURVES........................................................... 164

C4 SINGLE TOWN MAIN SUPPLY................................................................................... 165

C5 PUMPS DRAWING DIRECT FROM A SINGLE TOWN MAIN SUPPLY................... 168

C6 DUAL TOWN MAIN SUPPLIES................................................................................... 176

C7 HIGH-RISE SYSTEMS WITH BOOSTED TOWN MAIN SUPPLIES.......................... 183

C8 PUMPS DRAWING FROM PUMP SUCTION TANKS ................................................ 189

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FOREWORD Automatic fire sprinklers can provide a level of fire safety for the occupants of buildings, and fire service personnel engaged in search, rescue and firefighting operations whilst providing a level of fire protection for buildings and structures.

The scope of property protection provided through compliance with this document is deemed to be consistent with the respective performance requirements of the BCA. Compliance with other applicable legislation should not be assumed.

When designing a sprinkler system there is a need to consider how other fire safety systems may impact on the function and operation of a sprinkler system. Other active fire safety systems that can either interface or integrate with a fire sprinkler system, include; fire automatic heat and smoke detection systems, emergency warning and intercommunication systems and smoke management systems.

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15

S E C T I O N 1 S C O P E A N D G E N E R A L

1.1 SCOPE

This Standard specifies a deemed-to-satisfy Building Solution for the design and installation of automatic fire sprinkler systems in buildings and structures listed in BCA Table E1.5.

1.2 REFERENCED DOCUMENTS

The following documents are referred to in this Standard:

AS 1074 Steel tubes and tubulars for ordinary service

1281 Cement mortar lining of steel pipes and fittings

1349 Bourdon tube pressure and vacuum gauges

1432 Copper tubes for plumbing, gasfitting and drainage applications

1516 The cement mortar lining of pipelines in situ

1579 Arc-welded steel pipes and fittings for water and waste-water

1650 Galvanized coatings on ferrous articles Metric Units

1670 Fire detection, warning, control and intercom systems—System design, installation and commissioning

1670.1 Part 1: Fire

1674.1 Safety in Welding and Allied Processes Part 1 – Fire Precautions

1724 Cast grey iron pressure pipes and fittings with bolted gland joints

1735 Lifts, escalators and moving walks

1834 Material for soldering Part 1 – Solder Alloys

1873 Powder-actuated (PA) hand-held fastening tools

2118 Automatic fire sprinkler systems 2118.1 Part 1: General requirements Part 2 Not referenced in 06 code except in approval section 2118.3 Part 3: Deluge 2118.6 Part 6: Combined sprinkler and hydrant

2201 Intruder alarm systems 2201.2 Part 2: Monitoring centres 2419.1 Part 1: Fire hydrant installations - System design, installation and

commissioning

2544 Grey iron pressure fittings

2941 Fixed fire protection installations—Pumpset systems

3688 Water supply—Metallic fittings and end connectors

4041 Pressure piping

4118 Fire sprinkler systems 4118.1.1 Part 1.1: Components—Sprinklers and sprayers 4118.1.2 Part 1.2: Components—Alarm valves (wet) 4118.1.3 Part 1.3: Components—Water motor alarms

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4118.1.4 Part 1.4: Components—Valve monitors 4118.1.5 Part 1.5: Components—Deluge and pre-action valves 4118.1.6 Part 1.6: Components—Stop valves and non-return valves 4118.1.7 Part 1.7: Components—Alarm valves (dry) 4118.1.8 Part 1.8: Components—Pressure-reducing valves 4118.2.1 Part 2.1: Piping—General

4428 Fire detection, warning, control and intercom systems—Control and indicating equipment

4428.1 Part 1: Fire 4428.6 Part 6: Alarm signalling equipment

4254 Ductwork for air-handling systems in buildings AS/NZS

1167.1 Welding and Brazing Filler Metals Part 1 – Filler metal for brazing and braze welding

1668.1 Part 1 The use of ventilation and airconditioning in buildings—Fire and smoke control in multi-compartment buildings

3000 Electrical installations (known as the Australian/New Zealand Wiring Rules)

3013 Electrical installations—Classification of the fire and mechanical performance of wiring systems.

3500 Plumbing and drainage 3500.1 Part 1: Water services 3500.1.2 Part 1.2: Water supply—Acceptable solutions

1.3 DEFINITIONS

For the purpose of this Standard the following definitions apply.

1.3.1 Alarm signalling equipment (ASE)

Equipment complying with AS 4428.6, Alarm signalling equipment.

1.3.2 Alarm valve

A non-return valve that allows the water to enter the installation and operate the alarms when the installation pressure falls below the water supply pressure.

1.3.3 Appropriate Authority

The relevant authority as determined by the building regulatory legislation in each State and Territory.

1.3.4 Automatic inflow

Automatic flow into a tank to partially make up, within a prescribed time, water drawn off under operational conditions.

1.3.5 Building owner

The owner of a building or the authorised representative of the owner.

1.3.6 Building Solution

As defined within the Building Code of Australia

1.3.7 Compartment

A space that is enclosed by walls and a ceiling. The walls of the compartment enclosure may have openings to an adjoining space, provided there is a minimum depth of 200 mm

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from the ceiling to the top of the opening. Not to be confused with fire or smoke compartment as defined in the BCA.

1.3.8 Design area

An area containing the maximum number of sprinklers likely to operate when involved in a fire.

1.3.9 Design density

The minimum density of discharge of water in millimetres per minute (mm/min) for which a sprinkler installation is designed. It is determined by the discharge of the group of sprinklers in the design area, in litres per minute (L/min), divided by the area covered by that group in square metres (m2). Also known as ‘Design density of discharge’.

1.3.10 Designated building entry point (DBEP)

An entry point to a building that provides firefighters with information as to the location of the fire alarm.

1.3.11 Designated site entry point (DSEP)

An entry point to a site that provides firefighters with information as to the location of the building from which the fire alarm originated.

1.3.12 Effective height

As defined within the Building Code of Australia.

1.3.13 Fire and draft stop

A partition or bulkhead, extending from end to end and top to bottom of a concealed space, installed to delay the spread of fire and constructed from imperforate materials that are non-shatterable under fire conditions.

NOTES: 1 Examples of acceptable fire and draught stops include the following:

(a) Structural features such as a reinforced beam or steel joist extending to or through the ceiling, and a brick wall extended up through the ceiling to the floor above.

(b) A purpose-built partition mounted on wood or steel framework, constructed of 10 mm gypsum board, 0.6 mm sheet steel or 7 mm high-density tempered hardboard.

2 They have the following acceptable apertures: (a) Openings for the passage of individual pipes, conduits and airconditioning ducts,

provided that such openings are reasonably close fitting or sealed with fire resistant sealant.

(b) Openings not exceeding 2 m in width for the passage of groups of pipes, conduits and airconditioning ducts, protected by a ‘cut-off’ sprinkler or sprinklers as required to provide full protection to such openings.

1.3.14 High-rise

A multistorey building exceeding an effective height of 25 m (see Clauses 1.3.12 and 1.3.21).

1.3.15 Installation

The portion of a sprinkler system downstream from and inclusive of a control assembly.

1.3.16 K factor (nominal)

A constant that defines the pressure and flow characteristics of a sprinkler, as determined by the formula

PQK =

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where

Q = Flow, L/min

P = Pressure, kPa

1.3.17 Listed

Sprinkler equipment or materials that are demonstrated to meet the requirements of AS 4118 or have been tested in a specified manner and found suitable for use.

1.3.18 Maximum flow rate of the system (Qmax.)

The maximum flow rate of the system (Qmax.) occurs at the point of intersection of the maximum water supply curve and the hydraulically most favourable system requirement curve when the hydraulic characteristics are represented in accordance with the requirements of Clauses 12.7 and 12.9.

1.3.19 Monitoring centre

A facility that receives signals from a monitored site and transmits signals to a fire dispatch centre.

1.3.20 Multiple controls

Heat-sensitive sealed valves that control a single outlet or multiple outlets using either a glass bulb or a soldered link or lever as the heat-sensing device.

1.3.21 Multistorey

A building with a rise of more than two storeys, which may also be a high-rise building (see Clause 1.3.14) or with more than two storeys below the floor of the lowest storey providing egress to a road or open space.

1.3.22 Net positive suction head (NPSH)

The total inlet head, plus the head corresponding to the atmospheric pressure, minus the head corresponding to the vapour pressure. NPSH, as well as inlet total head, is referred to the reference plane. It is necessary to make a distinction between—

(a) required net positive suction head (NPSHR)—a function of pump design, which may be obtained from the pump manufacturer; and

(b) available net positive suction head (NPSHA)—a function of the system in which the pump operates, which can be calculated for any installation.

1.3.23 Open joists and exposed common rafters

A series of members (including purlins) spaced not more than 600 mm apart, measured from centre to centre of members.

1.3.24 Post or box pallet

Solid or mesh box with the open face uppermost, designed to be stacked one upon the other in a self-supporting manner.

1.3.25 Required duration of operation

The minimum period of operation of an automatic fire sprinkler system as required by Deemed-to-Satisfy Provisions of the BCA

1.3.26 Special sprinkler

A listed sprinkler other than those specified in Table 1.1 of AS 4118.1.1. (See also Clause 6.2.2.) Special sprinklers include the following:

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(a) Extended coverage sprinkler A type of spray sprinkler with a higher pressure requirement and a modified deflector specifically developed to achieve an extended maximum protected area.

(b) Large drop sprinkler A type of sprinkler that is capable of producing large water droplets, enabling better penetration of the fire plume and improved ability to control high-challenge fires.

(c) Early suppression fast response sprinkler (ESFR) A type of fast response sprinkler developed to provide fire suppression of high-challenge fires, which, in many instances, eliminates the need for in-rack protection. This sprinkler has special design requirements and limitations in respect to the building structure and the system application.

(d) Residential sprinkler A type of fast response sprinkler, developed for the type of fire hazard found in dwellings, with spray patterns and discharge rates specifically designed for life safety applications.

(e) Sealed water mist nozzle A fast response, sealed, spray nozzle listed as providing equivalent performance to pendent spray sprinklers for Light Hazard and Ordinary Hazard Group 1 and 2 application.

(f) Enhanced protection extended coverage (EPEC) A type of fast response sprinkler with enhanced fire control characteristics for extended coverage in Ordinary Hazard Group 3 applications.

C1.3.26 The difference between special sprinklers and standard sprinklers, in simple terms, can best be described as follows:

(a) Special sprinklers have been developed for a specific purpose, and the system design parameters must suit the sprinkler performance characteristics. (The sprinkler characteristics dictate the system design parameters required.) As such, standard sprinkler system design requirements, as specified in this Standard, may not be suited to systems incorporating special sprinklers. Design requirements for such systems should be determined with reference to Clause 2.3.3.

(b) Standard sprinklers have been developed to suit the particular system design parameters set down in Sections 9, 10, and 11 of this Standard. (The system design parameters dictate the required sprinkler characteristics.)

The design of systems using standard sprinklers is based on providing a given density of water over a specified floor area. Standard sprinklers were originally restricted to those conforming to specific thread and orifice sizes. The range has been extended to include sprinklers with larger thread and orifice size, provided the sprinklers suit the system design parameters of Sections 9, 10 and 11. These sprinklers include large orifice types, which are also often identified by reference

to a ‘K factor’ (a constant in the formulaP

QK = , see Clause 1.4.14).

1.3.27 Special sprinkler system

A system utilizing either in total, or in part, sprinkler types other than those listed in AS 4118.1.1. (See also Clauses 2.1.3 and 6.2.2.)

1.3.28 Sprayer

Special purpose nozzle for use in water spray systems with capabilities of extinguishing, containing or controlling fires involving hazards such as flammable liquids.

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C1.3.28 Sprayers generally are of two basic types, medium velocity and high velocity. Medium-velocity sprayers are either open or sealed with a heat-responsive element, producing a fine droplet spray with a limited distance of direct impingement. They are designed for the extinguishing, containing or controlling fires involving low-flashpoint liquids as well as for cooling protected (adjacent) areas exposed to fire. High-velocity sprayers are open-type sprayers producing a large droplet with high momentum and have a direct impingement distance of up to 5 m. High-velocity sprayers are designed for extinguishing, containing and controlling fires involving high-flashpoint liquids, principally by the emulsification of the burning fuel surface.

1.3.29 Sprinkler-protected building

A building equipped throughout with a sprinkler system installed in accordance with this Standard.

1.3.30 Sprinkler system

A system comprising components such as valves, alarms, pipework, sprinklers and water supplies designed to control fire in a building. Sprinkler systems may be either standard systems or special systems, and may be arranged to operate as one or a combination of the following:

(a) Wet system A system permanently charged with water both above and below the installation alarm valve (wet) (see Clause 8.10.1).

(b) Alternate wet and dry system A system that incorporates either a composite alarm valve, or a combination valve set comprising an alarm valve (wet) and an alarm valve (dry).

(c) Dry system A system permanently charged with air or inert gas under pressure, above the alarm valve (dry) and with water below (see Clause 8.10.2).

(d) Pre-action system A combination of a sprinkler system and an independent system of heat or smoke detectors installed in the same area as the sprinklers. A heat or smoke detector operates prior to the sprinklers, allowing the pre-action valve to open and water to flow into the sprinkler piping, before the first sprinkler starts to operate (see Clause 8.12.2).

(e) Recycling pre-action system A system with heat detectors and incorporating a pre-action flow control valve capable of repeated on/off cycles appropriate to the possible redevelopment of fire in the protected area. The cycling occurs as a result of heat detector operation which, as an electric interlock, causes the pre-action flow control valve to open and close.

(f) Deluge system A system of open sprinklers controlled by a quick-opening valve, (deluge valve) (see Clause 8.12.1) which is operated by a system of listed heat detectors or sprinklers installed in the same areas as the open sprinklers (see AS 2118.3).

(g) Tail-end system A system essentially similar to dry, alternate wet and dry, pre-action and deluge systems, with the limitation that it only forms an extension to a sprinkler installation.

1.3.31 Standard sprinkler

A sprinkler conforming to the thread sizes, deflector type and K factors specified in AS 4118.1.1, or spray sprinklers with K factors of 16.0 (ELO), 20.0 (VELO), 24.0 or 36.0. (See also Clause 6.2.1.)

Standard sprinklers include the following:

(a) Conventional sprinkler A sprinkler designed to produce a spherical type of discharge with a proportion of water being thrown upwards to the ceiling. A conventional sprinkler is usually designed with a universal type deflector enabling

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the sprinkler to be used in either the upright or pendent position. Some conventional sprinklers are made in two types: one suitable for use in the upright position and the other for use in the pendent position.

(b) Spray sprinkler A sprinkler designed to produce a parabolic discharge below the plane of the deflector with little or no water being discharged upwards to wet the ceiling. Spray sprinklers are made in two types: one suitable for use in the upright position and the other for use in the pendent position.

(c) Flush sprinkler A sprinkler designed for use with concealed piping where it is required, for reasons of appearance, to make the sprinklers inconspicuous.

NOTES: 1 A flush sprinkler is installed pendent, with the base flush to the ceiling, but has an

exposed heat-responsive element and retracted deflector which drops down to the normal position on actuation.

2 Flush sprinklers are normally used in hotel lobbies, dining rooms, offices, boardrooms and parts of retail stores. Flush sprinklers are not suitable for use in atmospheres that are corrosive or subject to a high dust content. Flush sprinklers utilizing chains to locate the deflector are only suitable for use with level ceilings unless specifically listed otherwise.

(d) Recessed sprinkler A sprinkler comprising a spray sprinkler provided with a separate escutcheon housing, usually two-piece adjustable, where part of the sprinkler yoke and heat-responsive element are mounted within the recessed housing.

NOTE: Escutcheon housings are used with the spray sprinkler to ensure that the response time of the heat-responsive element is not unduly impeded and that the discharge spray pattern is not obstructed.

(e) Concealed sprinkler A sprinkler comprising a spray sprinkler that is fully recessed in a concealed housing and fitted with a cover plate assembly designed to release at or before the operating temperature of the sprinkler.

NOTE: Concealed sprinklers provide the same unobtrusive appearance as flush sprinklers.

(f) Sidewall sprinkler A sprinkler designed for installation along the walls of a room close to the ceiling. A sidewall sprinkler provides a one-sided (half-paraboloid) discharge pattern directed outwards with a small proportion discharging on the wall behind the sprinkler.

NOTES: 1 Sidewall pattern sprinklers are not normally a substitute for conventional or spray pattern

sprinklers and their use is limited to such locations as offices, entrance halls, lobbies and corridors.

2 A sidewall sprinkler may be used to advantage in drying tunnels and hoods over papermaking machines where condensate dripping from sprinklers and pipework at the ceiling could be troublesome and also in certain other locations, such as shop windows and under platforms having low headroom, where sprinklers would be subject to damage.

(g) Dry pendent and dry sidewall sprinkler A sprinkler designed for use in portions of premises protected by a dry or an alternate wet and dry system where it is not practicable to install sprinklers in the upright position, or in a wet system where the sprinklers may be subject to frost.

NOTE: Dry pendent and dry sidewall sprinklers are designed having either conventional or pendent spray-type deflectors. Dry pendent and dry sidewall sprinklers are manufactured integral with drop pipes of varying lengths, the valve being so placed that there is no pocket or depression where water can be trapped.

(h) Dry upright sprinkler A sprinkler essentially the same as the dry pendent types except that an upright type deflector is incorporated.

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NOTE: A dry upright sprinkler is designed for use in wet systems for the protection of concealed spaces subject to freezing.

(i) Fast-response sprinkler A sprinkler that has a high level of thermal sensitivity, which enables it to respond at an early stage of fire development and belongs to the fast-response category (see AS 4118.1.1).

(j) Enlarged orifice sprinkler A sprinkler having a nominal 20 mm diameter orifice and a nominal 15 mm shank fitted with a metal rod extension (pintle), which is used for upgrading the density requirements of existing ordinary hazard installations (see AS 4118.1.1).

(k) Large orifice, extra large orifice and very extra large orifice sprinklers Types of sprinklers with increased orifice sizes to permit high-flow rates.

C1.3.30 The life safety aspects of a sprinkler system are improved by using fast response sprinklers. Fast response and quick response are synonymous terms.

1.3.32 Standard sprinkler system

A system utilizing sprinkler types as listed in AS 4118.1.1. (See also Clause 6.2.1.)

1.3.33 Thermal sensitivity

A measure of the response time index (RTI) and the conductivity factor © expressed in categories of RTI, being: fast response, special response or standard response (see AS 4118.1.1).

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S E C T I O N 2 S P R I N K L E R S Y S T E M D E S I G N D A T A

2.1 TYPES OF SPRINKLER SYSTEMS AND AREA LIMITATIONS

2.1.1 General

Sprinkler systems are either—

(a) standard sprinkler systems (see Clause 1.3.31 ); or

(b) special sprinkler systems (see Clause 1.3.27).

2.1.2 Standard sprinkler system

2.1.2.1 General requirements

A standard sprinkler system shall be arranged to operate as one or a combination of the following:

(a) Wet system.

(b) Alternate wet and dry system.

(c) Dry system.

(d) Pre-action system.

(e) Recycling pre-action system.

(f) Deluge system.

(g) Tail-end system.

Standard sprinkler systems shall comply with the requirements set out in Clauses 2.1.2.2 to 2.1.2.9, as applicable.

2.1.2.2 Wet systems

Wet systems shall not be installed in premises where there is danger, at any time, of the water in the pipes freezing or where the lowest average ambient temperature is less than 4°C.

Wet systems shall be so designed that the maximum floor area, excluding concealed spaces but including mezzanine floor areas, controlled by one control assembly, including tail-end extensions (see Clause 2.1.2.8) does not exceed the following:

(a) 9000 m2 for Light Hazard and Ordinary Hazard installations.

(b) 8000 m2 for High Hazard process occupancy installations

(c) 8000 m2 for High Hazard storage occupancy installations provided the total area of storage does not exceed 1000 m 2 and there is ceiling or roof protection only;

(d) 6000 m2 for High Hazard storage risk installations where the total area of storage exceeds 1000 m2 and there is ceiling or roof protection only;

(e) 8000 m2 for High Hazard storage occupancy installations provided the total area of storage has intermediate level sprinklers; or

(f) 4000 m2 for single installations controlling intermediate level sprinklers in storage racks, made up of the floor area occupied by the racks and the aisles combined.

Where single installations protect both High Hazard areas and Ordinary Hazard or Light Hazard areas, the High Hazard area shall not exceed the floor area specified in Items (b), (c), (d) or (e) above, as appropriate, and the total area shall not exceed 9000 m2.

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2.1.2.3 Alternate wet and dry systems (see Clause 1.3.29)

An alternate wet and dry sprinkler system shall incorporate either a composite alarm valve (see Clause 8.10.3) or a combination set comprising an alarm valve (wet) and an alarm valve (dry) (see Clauses 8.10.1 and 8.10.2). During winter months, the installation piping above the composite alarm valve, or alarm valve (dry) shall be charged with air and the remainder of the system, below the valve, shall be charged with water and, at other times, the system shall operate as a wet system as described in Clause 2.1.2.2.

Sprinklers in alternate wet and dry systems shall be installed in the upright position, above the line of pipe. An exception is allowed where listed dry pendent sprinklers (see Clause 1.3.30) are installed or where sprinklers have an anti-freezing device incorporated therein.

Piping shall be arranged with slope for drainage (see Clause 7.4).

Alternate wet and dry systems shall be so designed that the maximum floor area, including mezzanine floor areas, controlled by one control assembly, including tail-end extensions (see Clauses 2.1.2.8 and 2.1.2.9), does not exceed the following:

(a) Where an accelerator or exhauster is used—

(i) 3700 m2 for Light Hazard and Ordinary Hazard systems; and

(ii) 2100 m2 for High Hazard systems.

(b) Where an accelerator or exhauster is not used—

(i) 2500 m2 for Light Hazard and Ordinary Hazard systems; and

(ii) 1400 m2 for High Hazard systems.

2.1.2.4 Dry systems (see Clause 1.3.29)

A dry sprinkler system shall be permanently charged with air or inert gas under pressure above the alarm valve (dry) and with water below the valve.

Dry systems permit sprinklers to be installed in buildings where the temperature conditions are maintained close to or below freezing, such as in cool stores, or fur vaults, or where the temperature is maintained above 70°C, such as in drying ovens (see Clause 5.6.14).,

The floor area controlled by one control assembly in a dry system shall not exceed that prescribed in Clause 2.1.2.3 for alternate wet and dry systems.

Piping shall be arranged with slope for drainage (see Clause 7.4). Standard sprinklers shall only be installed in the upright position above the line of the pipe.

2.1.2.5 Pre-action systems (see Clause 1.3.29)

Pre-action systems may remain dry with atmospheric air above the alarm valve when they protect areas not exceeding 200 m2 otherwise they shall be permanently charged with air or inert gas under pressure. Where the systems are pressurized above the alarm valve, they shall be monitored so that an alarm is given on a reduction of pressure.

The pre-action alarm valve shall be operated as follows:

(a) For a single interlock pre-action configuration—solely by the system of heat or smoke detectors to allow the sprinkler piping to become charged with water prior to or following the operation of a sprinkler.

(b) For a double interlock pre-action configuration—by both the system of detectors and the monitored low-pressure alarm resulting from the operation of a sprinkler.

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The pre-action detection system may utilize a heat or smoke detection system complying with AS 1670.1 as referenced in the BCA or, where electrical supply is to be avoided, a sprinkler detection system charged with either air or water under pressure. In each case the detection system shall automatically initiate an alarm.

The heat or smoke detection system shall operate a solenoid valve or trip mechanism as one action to release the pre-action alarm valve. Solenoid valve wiring shall be fire resistant and supervised when the solenoid is not continuously energised as ‘fail-safe’, that is, set to release when de-energized.

The floor area controlled by one control assembly in a pre-action system shall not exceed that prescribed in Clause 2.1.2.2 for wet systems.

Where the piping could be subject to freezing, it shall be arranged with slope for drainage -(see Clause 7.4) and standard sprinklers shall be installed in the upright position above the line of pipe.

The installation spacing and location of heat or smoke detectors shall comply with the requirements of AS 1670.1 as referenced in the BCA.

C2.1.2.5 A single interlock system only becomes a wet system following the operation of the detection system, the objective being to prevent a discharge of water from piping or sprinklers that may have suffered mechanical damage.

A double interlock system offers the greatest safeguard against inadvertent water discharge by requiring that both the system of detectors and the sprinkler installation be activated before water is admitted to the installation piping.

2.1.2.6 Recycling pre-action systems

Re-closing the flow control valve shall be delayed for a period of 5 min, by means of an automatic timer, as a safety measure. Should the fire re-kindle and re-actuate the heat detectors, the flow control valve shall re-open immediately and water shall again flow from the open sprinklers.

The floor area controlled by one control assembly in a recycling pre-action system shall not exceed that prescribed in Clause 2.3.2.2 for wet systems.

The piping shall be arranged with slope for drainage (see Clause 7.4) and standard sprinklers shall be installed in the upright position above the line of pipe.

The installation and spacing of heat or smoke detectors in recycling pre-action systems shall comply with the requirements of AS 1670.1 as referenced in the BCA

2.1.2.7 Deluge systems (see Clause 1.3.29)

Deluge systems shall be in accordance with AS 2118.3.

C2.1.2.7 Deluge systems are designed primarily for special hazards such as those listed as High Hazard in Clause 2.2. Where any fire could be anticipated to be intense and with a fast rate of propagation. In such circumstances, it is desirable to apply water simultaneously over a complete zone in which a fire may originate by admitting water to open sprinklers or to medium- or high-velocity sprayers.

2.1.2.8 Tail-end systems (see Clause 1.3.29)

Tail-end systems shall form extensions to sprinkler systems.

The following limitations and specific requirements shall apply for tail-end installations:

(a) The total area of tail-end systems on one wet pipe installation shall not exceed 2500 m2. Any one tail-end system shall not exceed 1000 m2.

(b) The subsidiary stop valve shall be monitored in accordance with Clause 3.4.

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(c) Suitable drainage shall be provided.

(d) Tail-end systems connected to dry and alternate wet and dry installations shall be limited to dry systems.

2.1.2.9 Tail-end anti-freezing solution systems

Tail-end anti-freezing solution systems shall only be connected to wet pipe installations.

In addition to the requirements of Clause 2.1.2.8, the following requirements shall apply for tail-end systems incorporating anti-freezing solutions:

(a) Piping within the area subject to freezing shall be filled with anti-freezing solution and shall be arranged so as to prevent diffusion of water into that area.

(b) Anti-freezing solutions shall have a freezing point of not less than 10°C below the minimum temperature possible in the area subject to freezing.

(c) The area covered by any tail-end anti-freezing solution system shall not exceed 250 m2.

(d) The piping shall be arranged so that the interface between the anti-freezing solution and the water in the wet system is lower than the point of connection to the wet system.

(e) The following valves and fittings shall be incorporated in the piping:

(i) A subsidiary stop valve monitored in accordance with Clause 3.4.

(ii) A drain valve.

(iii) An upper test valve, not more than 350 mm nor less than 250 mm below the filling connection in the wet system.

(iv) A lower test valve, not less than 1.2 m below the upper test valve.

(v) A filling connection.

(vi) A non-return valve. The disc of the non-return valve shall have a 1 mm hole to allow for expansion of the solution during a temperature rise and thus prevent damage to sprinklers. All valves in the system piping shall be metal-faced.

NOTES: 1 These systems are suitable for use in small coolrooms and freezing chambers and other areas

such as loading docks and outhouses in localities subject to freezing conditions. 2 See Figure 2.1.2.9 for an arrangement of the fittings.

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DIMENSIONS IN MILLIMETRES

FIGURE 2.1.2.9 ARRANGEMENT OF SUPPLY PIPING AND VALVES, AND TAIL-END ANTI-FREEZING SOLUTION SYSTEM

2.1.3 Special sprinkler systems

2.1.3.1 General requirements

A special sprinkler system, as defined in Clause 1.3.26, shall be arranged to operate as one or a combination of the following:

(a) Wet system.

(b) Alternate wet and dry system.

(c) Dry system.

(d) Pre-action system.

(e) Recycling pre-action system.

(f) Tail-end system.

A special sprinkler system shall comply with the requirements set out in Clauses 2.1.2.2 to 2.1.2.9 and Clauses 2.1.3.2 to 2.1.3.5. NOTE: The use of special sprinklers in High Hazard deluge systems is not recommended unless the special sprinkler is listed for High Hazard applications. Deluge systems should utilize open standard sprinklers or listed medium- or high-velocity sprayers.

2.1.3.2 Specific requirements

2.1.3.2.1 General

Special sprinkler systems shall incorporate special sprinklers installed in accordance with the spacing, location, maximum and minimum pressure limitations, and other requirements set out in -

(a) the listing for the specific sprinkler;

(b) the manufacturer’s published data sheets, and

(c) the codes and Standards referenced therein.

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The critical design and installation requirements for special sprinkler systems are those that directly affect the performance of the sprinklers. They shall apply only to that part of each system downstream of the control assembly. Other issues, such as the maximum floor area controlled by one control assembly, alarm and monitoring systems, valving, pipe materials, hangers, bracing and the like, shall conform to the requirements of this Standard.

The maximum area covered by a special sprinkler installation shall be in accordance with Clause 2.1.2.2 to 2.1.2.9

2.1.3.3 ESFR sprinkler system

Special sprinkler systems incorporating ESFR sprinklers (see Clause 1.3.26) shall be wet systems and shall be designed in accordance with Factory Mutual Loss Prevention Data Sheets 2-2 and 8-9 and the requirements of this Section

C2.1.3.3 ESFR sprinkler systems are designed exclusively to suppress high-challenge fires in High Hazard storage occupancies. In many instances, in-rack sprinklers can be reduced or eliminated. The system is expected to discharge a large volume of water at high speed, directly onto a fire to suppress the fire before it is fully developed. ESFR sprinklers are quick-acting high-performance sprinklers which have the capability of suppressing fires within designated occupancies.

2.1.3.4 Special systems incorporating residential sprinklers

Residential sprinkler heads may be installed in wet pipe sprinkler systems conforming to this Standard, provided the following criteria are met:

(a) The installation of residential sprinklers is limited to sole occupancy units and their adjoining corridors in residential portions of buildings.

(b) The design requirements of the portion of the system utilizing residential sprinklers conform to Section 9, Light Hazard, and the number of sprinklers assumed to be in operation includes the hydraulically most unfavourable six sprinklers.

(c) Residential sprinklers are listed and installed in strict accordance with positioning, spacing and roof slope requirements. The minimum design density for residential sprinkler systems is 2 mm/min, but not less than that produced from the flow requirements of the individual sprinkler as a function of its spacing, roof slope, temperature rating and minimum pressure requirements.

(d) Special sprinkler systems incorporating residential sprinklers are designed such that the maximum floor area, excluding concealed spaces but including mezzanine floor areas, controlled by one control assembly, does not exceed 9000 m2.

(e) Concealed spaces are protected in accordance with Clause 5.6.

C2.1.3.4 Residential sprinkler system design criteria for buildings up to four storeys in involve concessions in terms of extent of sprinkler coverage. Such concessions have not been demonstrated to be applicable to taller buildings involving common service shafts, central HVAC systems, and the like. Therefore, these taller buildings should be protected in accordance with the requirements of this Standard.

Standard sprinkler systems that permit the inclusion of residential sprinklers are designated as special sprinkler systems.

2.1.3.5 Hydraulic calculation

Special sprinkler system designs shall utilize hydraulic calculation procedures, in accordance with Section 12.

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2.1.4 Sprinkler compatibility

Except where localized higher than normal ambient temperatures exist (see Clause 6.5), all sprinklers installed in a compartment shall be of the same category of heat response (RTI), temperature rating, K factor, type (Standard or Special) and sub type (Large Orifice, Large Drop, ESFR, etc.).

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S E C T I O N 3 E X T E N T O F P R O T E C T I O N A N D S Y S T E M M O N I T O R I N G

3.1 PROTECTION AGAINST EXPOSURE HAZARDS

3.1.1 General

Where compliance with the BCA requires an external wall to be protected by a sprinkler system, clauses 3.1.2 to 3.1.7 shall apply.

3.1.2 Sprinklers

All sealed sprinklers used for exposure protection shall be rated as fast response, as defined in AS 4118.1.1, and shall have a temperature rating of 93°C.

Sprinklers shall be any of the following types and orientation:

(a) Pendent spray (SP)—mounted horizontally with the deflector towards the window or wall.

(b) Upright spray (SU)—mounted horizontally with the deflector away from the window or wall.

(c) Pendent sidewall—(WP) mounted pendent and oriented to direct the spray towards the window or wall.

(d) Pendent sidewall—(WP) mounted horizontally and oriented to direct the spray downwards and parallel to the window or wall.

(e) Horizontal sidewall—(WH) mounted pendent and oriented to direct the spray downwards and parallel to the window or wall.

(f) Sprinklers specifically designed for the purpose and located and spaced in accordance with their listing.

Conventional sprinklers (CU/P) shall not be used, except in the case of protection beneath roof overhangs. Sprinklers beneath roof overhangs shall not be considered a substitute for protection of walls.

3.1.3 Shielding

Where building features do not shield sprinklers to prevent cooling from sprinklers operating above, such sprinklers shall be fitted with metal shields not less than 80 mm diameter.

C3.1.3 The use of sprinkler shields as a device for heat collection has been shown in fire tests to be of no value as an aid for sprinkler operation compared to a non-shielded sprinkler.

3.1.4 Sprinkler spacing and location

Unless specifically listed otherwise, sprinklers shall be located in accordance with Tables 3.1.4(A) and 3.1.4(B).

In addition to the requirements contained in Tables 3.1.4(A) and 3.1.4(B), a sprinkler shall be positioned not more than 1.25 m horizontally from—

(a) the vertical extremities of the protected surface;

(b) the vertical extremities of each glazed opening, with the sprinkler located within the opening; and

(c) the centre of any building feature such as downpipes and glazing bars or mullions that project more than 40 mm from the protected surface.

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Where vertical glazing bars or mullions project more than 40 mm from the glazed surface and are spaced not more than 1660 mm centre to centre, every alternate sprinkler may be positioned on the centre-line of a mullion or glazing bar, provided the sprinklers are positioned within 1.25 m of each side of any vertical glazing bar or mullion that exceeds 40 mm in width.

TABLE 3.1.4(A)

SPRINKLER SPACING

Measurement Spacing Measured

Max. Min. Point of measurement

Horizontal Horizontally 2.5 m 1.8 m (see Note) Centre of sprinkler

Vertical Vertically 4.0 m N/A Deflector to deflector

NOTE: The 1.8 m minimum distance may be reduced where sprinklers are separated by a baffle or building feature that will prevent cooling from an adjacent operating sprinkler.

TABLE 3.1.4(B)

SPRINKLER LOCATION

Measurement, mm Orientation Measured

Max. Min. Point of

measurement

Horizontal Vertically below top of protected surface 100 50 Centre of sprinkler

Pendent Vertically below top of protected surface 100 50 Sprinkler deflector

SP and SU horizontal (spray towards wall) Horizontal from wall 300 100 Sprinkler deflector

WP pendent (spray towards wall) Horizontal from wall 300 100 Centre of sprinkler

WP horizontal (spray parallel to wall) Horizontal from wall 100 50 Sprinkler deflector

WH pendent (spray parallel to wall) Horizontal from wall 100 50 Centre of sprinkler

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DIMENSIONS IN MILLIMETRES

FIGURE 3.1.4 (A) GLAZED OPENINGS—TYPICAL ORIENTATION AND LOCATION OF SPRINKLERS

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Glazed openings in external wall Mullions or glazing bars projecting

not more than 40 mm from the glazed surface Maximum spacing of sprinklers

FIGURE 3.1.4 (B) GLAZED OPENINGS—SPACING OF SPRINKLERS

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Part (a)

Part (b)

DIMENSIONS IN MILLIMETRES

FIGURE 3.1.4 (c) GLAZED OPENINGS—SHIELDED BY MULLIONS—SPACING OF SPRINKLERS

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3.1.5 Piping

External sprinklers shall be fed either individually by range pipes or as groups by dedicated distribution pipes connected to a distribution pipe of the internal sprinkler system.

Pipe sizes shall be determined by full hydraulic calculation methods.

C3.1.5 In cases where excessive sprinkler system downtime may be occasioned by the post-fire replacement of external sprinklers, groups of external sprinklers should be connected by dedicated distribution pipes fitted with locked-open isolation valves. The fitting of locked-open sectional stop valves on connections to external protection can greatly decrease the time taken to restore a system following an operation of the external sprinklers and should be considered for all such installations.

3.1.6 Performance

Sprinkler systems that incorporate exposure protection shall be fully hydraulically designed so that the flow from any external sprinkler shall be not less than 75 L/min when the required maximum numbers of external sprinklers are operating.

Where the area to be protected by an individual sprinkler is less than 2.5 m wide, the flow rate may be reduced proportionally subject to a minimum end-head pressure of 70 kPa.

The required number of sprinklers assumed to be in simultaneous operation shall be the number of sprinklers opposed to each exposure hazard, up to a maximum of 18.

Hydraulic calculation methods shall be in accordance with Section 12.

3.1.7 Water supply

If the maximum calculated flow and pressure requirements of the exposure protection are in excess of that required for the internal sprinklers alone, the water supply shall be increased to cover the excess.

3.2 ALARM SIGNALLING

3.2.1 General

A sprinkler system shall be capable of automatically activating alarm signalling equipment as required by Specification E1.5 of the BCA. Alarm signalling equipment shall comply with AS 4428.6.

3.2.2 Integrity and marking requirements—Electrical wiring

Wiring from system pressure switches to the ASE shall comply with AS/NZS 3013 with a minimum rating of WS51W, and the mechanical rating upgraded dependent on the hazard defined in accordance with AS/NZS 3013. Where connection to the ASE is duplicated and routed via separate signal paths, the minimum cable rating shall be WSX1.

3.3 SYSTEM COMPONENT FAULT MONITORING

3.3.1 General

Fault monitoring of system components shall be provided in accordance with Clauses 3.5.2 to 3.5.5.

3.3.2 Fault monitoring devices

3.3.2.1 General

Class A fault monitoring devices shall be installed except where the monitored components are located within a secure area or room with access restricted by means of a security device or system, in which case Class B devices may be used.

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Class A valve monitoring devices, complying with AS 4118.1.4, shall be installed to provide tamper resistance and monitoring as required by Clause 3.5.2.2. Class B valve monitoring devices shall be appropriately listed for the purposes of monitoring the valve status as required by Clause 3.5.2.3.

3.3.2.2 Class A monitoring devices

Class A monitoring devices shall transmit a signal upon—

(a) a change of status of the monitored component;

(b) an attempt to tamper with or bypass the monitoring device; and

(c) an attempt to tamper with or bypass the connection to the monitoring centre.

3.3.2.3 Class B monitoring devices

Class B monitoring devices shall transmit a signal upon a change of status of the monitored component.

3.3.3 Systems to be monitored

Continuous system monitoring shall be installed—

(a) in systems containing High Hazard areas greater than 300 m2;

(b) in high-rise buildings; and

(c) where required to facilitate monthly testing or otherwise required by acts or regulations.

3.3.4 Components to be monitored

Where required by Clause 3.5.3, the following components shall be monitored:

(a) Water supply stop valves excluding underground key-operated valves.

(b) Main stop valves.

(c) Subsidiary stop valves (see Clause 8.2.4).

(d) Power supply for each electric motor-driven pump.

(e) Controller ‘ready to start condition’ battery voltage.

(f) At the 4 h fuel level for each compression ignition engine-driven pump.

3.3.5 Installation

Control and indicating equipment shall comply with the requirements of AS 4428.1 and AS/NZS 3000.

Fault signals from monitored components shall be connected to—

(a) a monitoring centre (see Clause 1.4.18);

(b) a Grade 2 central station complying with AS 2201.2, including a monitoring service; or

(c) a constantly attended in-house security facility.

Should the connection be severed, attention shall be drawn to this fact at the receiving station.

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S E C T I O N 4 W A T E R S U P P L I E S

4.1 SUPPLY

4.1.1 General

All sprinkler systems shall be provided with at least one reliable water supply drawn from an acceptable source and arranged to facilitate verification testing (see Clause 4.4). NOTE: For typical water supply and valve arrangements, see Appendix B.

4.1.2 Reliable water supply

A reliable water supply shall be capable of supplying the flow and pressure requirements of the sprinkler system for the required duration.

The minimum flow and pressure characteristics of a reliable town main water supply shall be taken as those nominated by the relevant water supply authority which it considers can be maintained for at least ‘95% of the time’. If the water supply authority is unable to provide ‘95% of the time’ data then the minimum water supply data shall apply.

C4.1.2 The grading of water supplies has been discontinued in this edition. Supply from a town main satisfying the criteria detailed in Clauses 4.1.3 and 4.2.2 is considered for the purpose of this Standard to be the benchmark for ‘a reliable supply’. Other acceptable sources of water are selected to equate with this level of reliability. A dual supply (as distinct from a duplicate supply) increases the reliability to a higher level but not to that assuring 100% redundancy. This higher level of reliability is intended to cater for more severe evacuation problems associated with high-rise buildings.

4.1.3 Acceptable sources of water supply

The following sources of water supply shall be acceptable:

(a) Town main (see Clause 4.3.2).

(b) Town main with automatic booster pumps (see Clause 4.3.2.2).

(c) A private system water supply (see Clause 4.3.3).

(d) A private system water supply with automatic booster pumps (see Clause 4.3.3.1).

(e) Suction tank with automatic pumps (see Clause 4.3.4).

(f) Natural sources such as rivers, lakes or underground water supply, subject to the conditions set out in Clause 4.3.5, with automatic pumps.

(g) Gravity tank (see Clause 4.3.6).

(h) Elevated private reservoir (see Clause 4.3.7).

(i) Pressure tank—permissible for Light and Ordinary Hazard 1 classes only (see Clause 4.3.8).

4.2 DUAL WATER SUPPLIES

4.2.1 General

Dual water supplies, where required in accordance with BCA Specification E1.5, shall comprise any two of the following:

(i) Town main (see Clause 4.3.2).

(ii) Town main with automatic booster pumps (see Clause 4.3.2.2).

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(iii) A private system water supply (see Clause 4.3.3).

(iv) A private system water supply with automatic booster pumps (see Clause 4.3.3.1).

(v) Suction tank with automatic pumps (see Clause 4.3.4).

(vi) Natural sources such as rivers, lakes or underground water supply, subject to the conditions set out in Clause 4.3.5, with automatic pumps.

(vii) Gravity tank (see Clause 4.3.6).

(viii) Elevated private reservoir (see Clause 4.3.7).

(ix) Pressure tank—permissible for Light and Ordinary Hazard 1 classes only (see Clause 4.3.8).

4.2.2 Acceptable arrangements

4.2.2.1 Independent arrangement

Dual water supplies shall be independent, or form part of a gridded town main system, and shall have stop valves so arranged that in the event of a breakdown at least one supply remains operative.

4.2.2.2 Individual connections

Where dual water supplies consist of two individual connections from a town main system, each connection shall be carried separately to inside the building structure, as follows:

(a) Where booster pumps are installed, each connection from the town main system shall be carried separately to the pump suction manifold described in Clause 4.3.8.3. An isolating valve shall be installed upstream of the pump suction manifold on each connection from the town main system. Each of these two isolating valves shall be secured open and shall be positioned as close as practicable to the isolating valves provided, in accordance with the requirements of Clause 4.3.8.3 at each pump inlet (see Figure 4.2.2.2(A)).

(b) Where booster pumps are not installed, each connection from the town main system shall be carried separately to a point as close as practicable to the sprinkler-protected building, where they may be interconnected. A single (combined main) connection may be carried from the interconnection point into the building (see Figure 4.2.2.2(B)).

C4.2.2.2(b) The isolating valve on each of the two connections from the town main system, required upstream and in close proximity to the pump suction manifold, provide a means of closing off any damaged or non-operational town main connection, thus preventing any operating pump from drawing air (see also Clause 4.3.8.3).

4.2.2.3 Pumps

Where each supply requires a pump, one pump shall be compression ignition engine-driven, the other may be electric motor-driven.

4.2.2.4 Tanks

Where both supplies are comprised of tanks, with or without pumps, the tanks shall be either separate units or a single unit partitioned to hold the required water storage capacity in each compartment. NOTE:Where there are two or more installations in one building, it is permitted to have the second and subsequent installation supplied by a single pipe taken downstream of the interconnection of the two supplies (see Figure 4.2.2.2(B).

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FIGURE 4.2.2.2 (A) DUAL TOWN MAIN WATER SUPPLIES—BOOSTED

FIGURE 4.2.2.2 (B) DUAL TOWN MAIN WATER SUPPLIES—UNBOOSTED

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4.3 GENERAL WATER SUPPLY PROVISIONS

4.3.1 General

4.3.1.1 Pressure considerations

The pressure applied to any sprinkler or component shall not exceed 1.2 MPa or the maximum listed working pressure of the component, whichever is the lesser.

Maximum pressure calculations shall include allowance for anticipated maximum water supply pressures, such as pressure fluctuation in town mains and pumps operating in a closed system condition.

4.3.1.2 Additives

Corrosive chemicals such as sodium silicate (or derivatives of sodium silicate), brine or other chemicals shall not be used for stopping leaks, while hydrostatically testing systems, or for any other purpose.

Additives intended for Legionella or microbiologically influenced corrosion (MIC) prevention, foam production or freezing point depression, are acceptable provided they do not adversely affect the performance of the sprinkler system. Such additives shall be replenished after alarm testing or whenever water is removed from the system.

Systems incorporating additives shall comply with the backflow prevention requirements of AS/NZS 3500.1.2 and the relevant water supply authority. The hydraulic characteristics of the backflow prevention device shall be considered when determining the available system supply pressure (see Section 12).

4.3.1.3 Water quality

The water supply requirements for sprinkler systems are based on the assumption that the source of water is a potable supply. Where this is not the case, such as sea water, raw or artesian water, consideration shall be given to the compatibility of pipe and components, the health, safety and environmental aspects of waste water, the maintenance requirements and the expected life of the system.

4.3.1.4 Backflow prevention

Where double check valve (DCV) backflow prevention is required by the appropriate authority or AS 3500.1.2, the DCV shall be installed in the water supply upstream of the sprinkler control valve assembly and fitted with above-ground isolation valves chained and padlocked in the open position.

4.3.2 Town main water supply

4.3.2.1 General

A town main system to be used for supplying a sprinkler system shall comply with the following requirements:

(a) The town main system shall be fed from a source of at least 1 ML capacity plus, for High Hazard class systems, the required stored capacity given in Section 11.

(b) Any stop valves on the branch connection from the town main and under the control of the occupier of the building containing the installation shall be secured in the open position.

(c) The town main shall be capable of supplying hydrant flows in excess of the sprinkler system demand. To provide for this demand, the following hydrant flows shall be deducted from the minimum town main hydraulic characteristic (see Clause 12.7.2(a))—

(i) for Light Hazard ..............................................................................600 L/min;

(ii) for Ordinary Hazard/High Hazard............................................ 1200 L/min; and

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(iii) for buildings of fire compartments greater than 10 000 m2 ............... 1800 L/min.

4.3.2.2 Pumps drawing from a town main supply

4.3.2.2.1 General

Pumps may draw directly from a town main provided the following criteria are met:

(a) The water supply authority requirements are met.

(b) The town main is capable of providing water at the maximum flow rate of the system Qmax. (see Clause 1.3.18)).

(c) The combined output of the town main and either pump (or two pumps if three are installed) meets the maximum flow and pressure requirements of the system (see Clause 4.3.8.4 and Figure 4.3.8.4(A).

4.3.2.2.2 Single supply

Where a boosted town main is the sole supply to a system, either one of the following shall apply:

(a) Two automatic pumps, at least one of which shall be compression-ignition engine driven. The other may be electric motor-driven. Each pump shall be capable of providing independently the necessary flow and pressure; or

(b) Three automatic pumps, at least two of which shall be compression ignition engine-driven, and any two of which shall be capable of providing in aggregate the necessary flow and pressure.

4.3.2.2.3 Dual supply

Where a dual water supply consists of two boosted town mains, at least one automatic booster pump is required per town main supply, provided the pumps share a common pump suction manifold, in accordance with the requirements of Clause 4.3.8.3.

4.3.3 Private system water supply

4.3.3.1 General

Private system water supplies that provide the combined requirements of fire, domestic and industrial systems, in addition to the sprinkler flow and pressure requirements, shall be in the form of a ring main complying with the following:

(a) The ring main shall be capable of providing the combined peak flow requirements of all connected systems in addition to meeting the sprinkler system flow and pressure requirements for the specified time.

(b) Any stop valves on branch connections to a sprinkler system from the ring main, apart from those underground, shall be secured in the open position.

Flow and pressure tests to establish the adequacy of the water supply to the sprinkler system shall be carried out when the draw-off for other purposes is at its peak.

4.3.3.2 Pumps drawing from a private system water supply

4.3.3.2.1 General

Pumps may draw directly from a private system water supply, provided the following criteria are met:

(a) The private system water supply is capable of providing water at the maximum flow rate of the system (Qmax.) (see Clause 1.3.18), plus the excess flow required by Clause 4.3.2.1(c).

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(b) The combined output of the private system water supply and either pump (or two pumps if three are installed) meets the maximum flow and pressure requirements of the system (see Clause 4.3.8.3 and Figures 4.3.8.4(A) and (B)).

4.3.3.2.2 Pressure boosting

Where pressure boosting is required to satisfy the system flow and pressure requirements, either one of the following shall be provided:

(a) Two automatic pumps, at least one of which shall be compression ignition engine- driven. The other may be electric motor-driven. Each pump shall be capable of providing independently the necessary flow and pressure.

(b) Three automatic pumps, at least two of which shall be compression ignition engine- driven, and any two of which shall be capable of providing in aggregate the necessary flow and pressure.

In each case the pumps shall be capable of operating in parallel, that is, they shall have similar pressure and flow characteristics.

4.3.4 Pump suction tank water supply

4.3.4.1 General

Pump suction tanks shall have an effective capacity as prescribed in BCA Specification E1.5.

Pump suction tanks shall be constructed from concrete, steel or fibreglass. Any internal membrane or liner incorporated in the tank design shall be permanently bonded to the tank to prevent separation and shall be listed for the purpose.

Fibreglass tanks or tanks having an internal membrane, or liner incorporated in the design, shall be located at least 6 m from a non-sprinkler protected building or be located in a sprinklered area.

Each pump suction tank shall be fitted with a device to indicate the depth of water, that is, full, three-quarters, half, quarter and empty.

The water supply for suction tank filling shall be capable of completely refilling the tank within the following times:

(a) Single supply tanks :

(i) Light Hazard ............................................................................................. 6 h.

(ii) Ordinary Hazard ....................................................................................... 12 h.

(iii) High Hazard ............................................................................................. 18 h.

(b) Dual supply tanks—One tank ............................................................................. 18 h.

Where the supply water enters the tank provision shall be made to minimize the entrainment of air.

Suction piping drawing from more than one pump suction tank, or more than one compartment of a sectional tank, shall be fitted with a stop valve adjacent to each tank outlet.

Except where hydraulically precluded due to tank elevation, waste water from the water supply flow test, pressure relief, and circulation relief facilities shall be piped to the tank. Where water returns to the tank, provision shall be made to minimize the entrainment of air.

4.3.4.2 Effective capacity

When calculating the effective capacity of a pump suction tank, the depth shall be taken as the measurement between the normal water level in the tank and the low water level X

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shown in Figure 4.3.4.2. Low water level X is calculated to be the lowest level before a vortex is created causing the pump to draw air (see Figure 4.3.4.3).

Where the suction pipe is taken from the side of the tank as shown in Figure 4.3.4.2(b), the clearance between the base of the tank and the lowest level of the pump suction pipe shall be not less than dimension B in Figure 4.3.4.2 (b).

Where a sump is formed in the base of a suction tank from which the suction pipe draws water, the sump shall be not smaller than indicated in Figure 4.3.4.2 in which the position of the sump is shown with broken lines. In addition, the sump width shall be not less than 3.6d, where d is the nominal diameter of the suction pipe. The point of entry of water to the suction pipe shall be located centrally across the width of the sump.

Nominal diameter of

suction pipe Dimension A Dimension B

65 80

100

250310370

80 80

100

150 200 250

500620750

100 150 150

300 350 400

9001 0501 200

200 250 300

DIMENSIONS IN MILLIMETRES

NOTE: Where a vortex plate is installed refer to Figure 4.3.4.3.

FIGURE 4.3.4.2 EFFECTIVE CAPACITY OF PUMP SUCTION TANKS

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4.3.4.3 Vortex inhibitor

Where a vortex inhibitor in the form of a flat circular plate at the suction inlet is used, it shall be designed as shown in Figure 4.3.4.3 and to the following formulae:

Hm = 0.5d where d > DN 150

or 0.75d where d ≤ DN 150

D = Ha

Qmax. 68.17×

Where

Hm = minimum clearance under plate, in millimetres

Ha = actual clearance under plate, in millimetres

d = nominal diameter of suction pipe, in millimetres

D = minimum diameter of plate, in millimetres

Qmax. = maximum flow rate, in litres per min (see Clause 1.3.18)

The plate shall be not less then 10 mm thick. It shall be effectively protected from corrosion.

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DIMENSIONS IN MILLIMETRES

FIGURE 4.3.4.3 VORTEX INHIBITORS

4.3.4.4 Pumps drawing from pump suction tanks

Pumps drawing from pump suction tanks shall comply with either one of the following:

(a) Two automatic pumps, at least one of which shall be compression ignition engine- driven. The other may be electric motor-driven. Each pump shall be capable of providing independently the necessary flow and pressure.

(b) Three automatic pumps, at least two of which shall be compression ignition engine- driven, and any two of which shall be capable of providing, in aggregate, the necessary flow and pressure.

4.3.5 Supply from natural source

4.3.5.1 General

Where the suction pipe draws from a suction chamber fed from a virtually inexhaustible natural source such as a river, channel, lake or the like, the design and dimensions specified in Figure 4.3.5 and Clause 4.3.5.3 shall apply.

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NOTE: For clarity, horizontal dimension of chambers are shown longer than acceptable minimum.

FIGURE 4.3.5 MINIMUM DIMENSIONS FOR SUPPLIES FROM INEXHAUSTABLE SOURCE

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4.3.5.2 Slope of inlet

Pipes, conduits and beds of open-topped channels shall have a continuous downward slope towards the jackwell or suction pit of at least 1:125.

4.3.5.3 Diameters of pipes

The diameters of feed pipes or conduit shall be determined from the following formula:

D = 21.68 Qmax. 0.357

where

D = internal diameter, in millimetres

Qmax. = maximum flow rate of pump (see Clause 1.3.18)

4.3.5.4 Depth of inlet

The top of the pipe or conduit inlet shall be not less than one diameter below the lowest known water level.

4.3.5.5 Depth of water

The depth (d) of water in open channels or weirs, and above the weir between the settling chamber and suction chamber, shall be not less than that shown in Table 4.3.5.5 for the corresponding width (W) and maximum flow rate of the pump (Qmax.). Each suction inlet shall be provided with a separate suction and settling chamber.

The total depth of open channels and weirs shall be sufficient to accommodate the highest known water level of the water source.

TABLE 4.3.5.5

MINIMUM DEPTH OF WATER AND WIDTH OF OPEN CHANNELS AND WEIRS FOR

CORRESPONDING INFLOWS

Depth (d) , mm

250 500 1 000

Width (W) Qmax.

Width(W) Qmax.

Width (W) Qmax.

88 125 167

280 497 807

82 112 143

522 891

1 383

78 106 134

993 1 687 2 593

215 307 334

1 197 2 064 2 342

176 235 250

1 960 3 159 3 506

163 210 223

3 631 5 647 6 255

410 500 564

3 157 4 185 4 953

291 334 361

4 482 5 592 6 340

254 286 306

7 825 9 577

10 749

750 1 113 1 167

7 261 12 054 12 792

429 527 539

8 370 11 415 11 816

353 417 425

13 670 18 066 18 635

1 500 2 000 4 500

17 379 24 395 60 302

600 667 819

13 903 16 271 21 949

462 500 581

21 411 24 395 31 142

— — 1 000 29 173 667 2 000

38 916 203 320

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4.3.5.6 Dimensions of suction and settling chambers

The dimension of the suction chamber and the location of suction pipes from the walls of the chamber, their depth below the lowest known water level and clearance from the bottom shall comply with the requirements of Clause 4.3.4.2.

The settling chamber shall have the same width and depth as the suction chamber and a length not less than 4.4√H where H is the depth of the settling chamber in metres.

4.3.5.7 Inlet screens

Conditions required for inlet screens are as follows:

(a) Pipe or conduit The inlet to a pipe or conduit feeding the settling chamber shall be fitted with a strainer with an aggregate clear opening not less than five times the cross-sectional area of the pipe or conduit. Individual openings in the strainer shall not allow a 25 mm diameter sphere to pass through. Provision shall be made for removal of the strainer for cleaning.

(b) Weir or open-top channels Weirs and open-top channels feeding the settling chamber shall be fitted with a removable screen of wire mesh or perforated metal plate with an aggregate clear opening below water level of 150 mm2 for each litre per minute of the maximum flow output of the pump (Qmax.). Two screens shall be provided, one in use with the other in a raised position, ready for interchange when cleaning is necessary. The screens shall be of sufficient strength to withstand the force applied by the water should they become obstructed.

NOTE: Consideration should be given to the method of isolation of the settling chamber for periodical cleaning and maintenance.

(c) Suction inlet drawing direct from source Where the suction inlet draws directly from the source, a walled area not smaller than that required for suction chambers (see Clause 4.3.5.6) shall be provided. Where the wall extends above the surface of the water, apertures shall be provided and fitted with screens complying with the requirements of Clause 4.3.5.7(b). Where the top of the wall is below the surface of the water level, a screen shall be fitted between the top of the wall and the highest known water level. Such screens shall provide an area not less than that required by Clause 4.3.5.7(b) at the lowest known water level.

Provision shall be made for access to the screens for cleaning.

4.3.5.8 Pumps drawing from a natural source

Pumps drawing from a natural source of water supply shall comply with either one of the following:

(a) Two automatic pumps, at least one of which shall be compression ignition engine- driven. The other may be electric motor-driven. Each pump shall be capable of providing independently the necessary flow and pressure.

(b) Three automatic pumps, at least two of which shall be compression ignition engine- driven, and any two of which shall be capable of providing, in aggregate, the necessary flow and pressure.

4.3.6 Gravity tank water supply

A gravity tank shall comply with the following requirements:

(a) The gravity tank shall have an effective capacity as prescribed in BCA Specification E1.5, and be located at a height sufficient to provide the maximum pressure requirement of the system. Each gravity tank shall be fitted with a device to indicate the depth of water, that is, full, three-quarters, half, quarter and empty.

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(b) The quantity of water required for the sprinkler installation shall be automatically maintained. If the tank forms the sole supply to the sprinkler system, the supply to the tank shall be capable of refilling the tank to the capacity required within 6 h. If the rate of input of the supply to the tank is less than that required to refill it within 6 h, the capacity of the tank shall be increased by the amount of the shortfall.

NOTE: Should the capacity of the tank exceed the system requirements, it is permissible to draw upon the surplus for other purposes by means of an outlet pipe on the side of the tank above the level of the quantity to be reserved for the sprinkler installation.

(c) A tank-isolating valve and non-return valve shall be provided on each tank outlet.

4.3.7 Pressure tank water supply

Pressure tanks shall comply with the following requirements:

(a) Pressure tanks shall be housed in a readily accessible position in, or on the roof, or in an area fitted with a sprinkler system and used for no purpose other than for the housing of fire protection water supplies. The tank shall be adequately protected against mechanical damage. The temperature of any room shall be maintained above 4°C.

Where the pressure tank enclosure is required to be sprinkler protected and is situated remote from the sprinkler protected premises such that it is impracticable to supply the pressure tank enclosure sprinklers from the installation control assembly, the sprinklers may be supplied from a point on the downstream side of the non-return valve on the supply pipe from the pressure tank.

The sprinkler supply connection shall be provided with a controlling stop valve locked in the open position and fitted on the supply pipe to the sprinklers, together with an alarm device with visible and audible indication of the operation of sprinklers provided at some suitable location (e.g., in the gatehouse or at the installation control assembly). A drain valve, DN 15, shall be provided downstream of the flow alarm to permit testing of the alarm.

(b) Pressure tanks shall be provided with an arrangement for maintaining automatically both the required air pressure, utilizing dual air compressors, and the required water level in the tank under non-fire conditions. The arrangement shall include an automatic warning system that indicates failure of the devices to restore the correct air pressure and water level within a reasonable period, the indication being given both visibly and audibly at some suitable location (e.g., in the gatehouse or at the installation control assembly). Power for this warning system shall be independent of the power supply to that feeding the air compressor and water pump supplying the tank.

(c) Pressure tanks shall be fitted with an air pressure gauge and a gauge glass calibrated to show the correct water level. Normally closed stop valves shall be fitted on both connections to the gauge glass. Stop valves and non-return valves shall be provided on both the water and air supply connections to the tank, and shall be fixed as close to the tank as practicable.

(d) Safety valves fitted to pressure tanks shall be fixed in such a position that the valve seating is water-sealed. A connection to the valve from the air-space above the waterline shall be provided to permit the rapid escape of air in the event of the valve opening. The setting of the safety valve for the correct working pressure shall be carried out by the installing engineers and the valve shall be so constructed that it can be tested without the setting being interfered with. The setting mechanism shall be protected against alteration by unauthorized persons. The outlet from the relief valve shall be an open end so that any leakage will be readily detected.

(e) A tank-isolating valve and non-return valve shall be provided on each tank outlet.

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(f) The proportion of air in the tank shall be not less than one-third of tank volume.

The air pressure (gauge) to be maintained in the tank shall be determined from the following formulas:

(i) Where the tank is above the highest sprinkler:

1

21 )(P

RPP

P −+

= . . . 4.3.8 (1)

(ii) Where the tank is below the highest sprinkler:

1

21 )79.9(P

RHPP

P −++

= . . . 4.3.8 (2)

where

P = gauge pressure to be maintained in tank, in kilopascals

P1 = atmospheric pressure (assume 100 kPa)

P2 = minimum calculated pressure required at the pressure tank outlet when all the water is expelled from the tank, in kPa

H = height between the highest sprinkler above the tank base, in metres

R = tank of volume totaltank in air of volume

4.3.8 Pump system design and installation

4.3.8.1 General

Pumpsets shall be designed and installed to comply with the requirements of AS 2941 and the following:

(a) Compression ignition engine-driven pumps shall be housed in an area fitted with a sprinkler system.

(b) Electric motor-driven pumps shall be housed in—

(i) a sprinkler protected area; or

(ii) a separate building of fire-resistant construction, which shall be used for no other purpose than for the housing of fire protection water supplies.

(c) Pumpsets shall be adequately protected against mechanical damage. The temperature of the room shall be maintained above 4°C for electric motor-driven pumps and above 10°C where compression ignition type engines are used. The installation of pump motors and electrical controls in pits, tunnels or the like are permitted only where approved by a relevant authority.

(d) Where a pump house, which is required to be sprinkler protected, is situated remote from the sprinkler-protected premises such that it is impracticable to supply the pump house sprinklers from the installation control assembly, the pump house sprinklers may be supplied from a point on the downstream side of the non-return valve on the supply pipe from the pump. The sprinkler supply connection shall be provided with a controlling stop valve locked in the open position fitted on the supply pipe to the sprinklers together with an alarm device with visible and audible indication of the operation of sprinklers provided at some suitable location (e.g., in the gatehouse or at the installation control assembly). A drain valve, DN 15, shall be provided downstream of the flow alarm to permit testing of the alarm.

Where operation of a pump is necessary to provide the flow and pressure requirements of the pump house sprinklers, pump starting shall be initiated by

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pressure sensors located on the pump discharge pipe upstream of the control valve assembly.

(e) A full-flow stop valve, padlocked in the open position, shall be fitted in the pump suction pipe to permit removal of the pump without draining water from the supply.

(f) Piping between the supply and the pump shall be arranged to prevent airlocks.

(g) There shall be a bypass around the pumps with a non-return valve on the bypass for water sources drawn from any of the following:

(i) Town main water supply.

(ii) Elevated private reservoir water supply.

(iii) Gravity tank water supply.

The diameter of the bypass shall be not less than the diameter of the pump discharge manifold.

4.3.8.2 Pump operating conditions

Sprinkler pumps shall not be installed under suction lift conditions. Sprinkler pumps shall be supplied with intake water under positive head.

For pumps to be considered under positive head, there shall be at least 2/3 of the required water storage above the centre-line of the pump which shall also be no more than 2.0 m above the low water level X (see Clause 4.3.4.2).

Where pumps draw from a natural unlimited water supply, such as a river, canal or lake, it shall be considered to be under positive head when the centre-line of the pump is located not less than 850 mm below the lowest known water level.

4.3.8.3 Suction piping

The diameter of the water supply connection to the pumps shall be such that a velocity of 4.0 m/s is not exceeded when either pump (or two pumps where three are installed) is operating at its maximum flow rate (Qmax.) (see Clause 1.3.18).

Suction pipe diameter shall comply with the requirements in AS 2941 and be not less than the suction inlet size of the pump.

Where pumps draw from pump suction tanks, the location of the entry point to the suction piping shall conform to the dimensions given in Figure 4.3.4.2.

Pump suction pipes shall be interconnected by a common manifold. This interconnection manifold shall be located adjacent to the pumps and shall be at least equal in diameter to the individual pump suction pipes. Each pump shall be fitted with an isolating (stop) valve at its inlet.

Means shall be provided to prevent any operating pump from drawing air from any non-operating interconnected pump through—

(a) the pump air vent pipes;

(b) the pressure relief valve piping;

(c) the pump anti-overheating circulating pipe; and

(d) the tank infill line drawing from the same source as the pump (see Figure D2).

The relevant requirements of Clauses 4.3.2.1, 4.3.3.1, 4.3.4.4 or 4.3.5.7 shall also apply (see also AS 2941).

4.3.8.4 Pumpset performance criteria

Pumpsets shall be capable of satisfying the flow and pressure requirements of any design area of the system under consideration, calculated at the lowest available suction pressure

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and the maximum flow rate of the system (Qmax.) (see Clause 1. 3.18). System requirement curves and the water supply curve shall be prepared in accordance with Clause 12.7. The supply curve shall intersect both the hydraulically most favourable and hydraulically most unfavourable system requirement curves at points at least 50 kPa above the calculated system pressure requirements.

Each pump driver shall be capable of meeting the power requirements of AS 2941.

Figures 4.3.8.4(A) and (B) illustrate typical acceptable curves for pumps drawing from a town main and from a static water source respectively.

NOTES: 1 Curves are drawn for the common datum. 2 The pump centre-line is the common datum. 3 Curves relate to flow and pressure only. 4 Power requirements have not been considered.

FIGURE 4.3.8.4 (A) TYPICAL SUPPLY CURVES—PUMP DRAWING FROM TOWN MAIN WITH PROVISION FOR HYDRANTS

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NOTES: 1 Curves are drawn for the common datum. 2 The pump centre-line is the common datum. 3 Curves relate to flow and pressure only. 4 Power requirements have not been considered.

FIGURE 4.3.8.4 (B) TYPICAL SUPPLY CURVES—PUMP DRAWING FROM STATIC WATER SOURCE WITH NO PROVISION FOR HYDRANTS

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4.3.9 Pumpsets

In addition to the requirements of AS 2941, pumpsets shall comply with the following:

(a) Each pump controller shall be actuated by a separate pressure sensor set to operate when the pressure in the installation has fallen to a value of not less than the highest pressure requirement for the system. Where pressure sensors are installed on a water supply manifold serving more than one installation, they shall be duplicated (wired in parallel) for each pump. Where more than one pump is provided, the pumps shall be arranged to start sequentially at a pressure not less than that stated above.

(b) A fall in water pressure in the sprinkler system, which is intended to initiate the automatic starting of the pump, shall at the same time provide a visible and audible alarm at some suitable location (e.g., in the gatehouse or at the installation control assembly). The starting of the pump(s) shall not cause the cancellation of the alarm. Where the pump is situated remote from the protected premises, visible and audible indication of the pump operation shall be provided at a similar suitable location. This alarm may share a common indicator with the pump running alarm (see also Clause 4.3.8.1(d)).

(c) Facilities shall be provided to reduce the applied water pressure to each starting device to simulate the condition of automatic starting at the required pressure. A separate hydraulic circuit shall be provided for each starting device. This can take the form of a drain valve on the hydraulic connection to the pump-start pressure switch with the provision of suitable permanent drainage facilities. To enable the cut-in pressure to be judged accurately, the drain valve shall be fitted with an orifice plate to reduce the rate of pressure drop.

To facilitate testing and servicing, an isolating valve shall be fitted on the hydraulic connection. A bypass and non-return valve, allowing flow towards the main, shall be provided to ensure pump starting is not disabled if the isolating valve is inadvertently left closed. A pressure gauge to indicate the pressure at which the pump starts shall be located between the isolating and drain valves so that it can be read during the pump starting test (see Figures 4.3.9(A) and (B)).

FIGURE 4.3.9 (A) TYPICAL PRESSURE SWITCH TEST ARRANGEMENT—CONNECTED TO AN INSTALLATION

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FIGURE 4.3.9 (B) TYPICAL PRESSURE SWITCH TEST ARRANGEMENT—CONNECTED TO AN INSTALLATION WATER SUPPLY MANIFOLD

4.4 PROVING OF WATER SUPPLIES

Facilities shall be provided on each sprinkler system to test the water supplies to verify that they satisfy the calculated flow and pressure requirements of the installed system.

The flow measuring device shall be installed at any point on the system downstream of the datum point to which the hydraulic calculations are referenced.

The test pressure gauge shall be installed at or immediately adjacent to the system hydraulic calculation datum point.

Where more than one hazard class is involved, whether on the same or separate installations, testing facilities shall be provided to enable the full range of flows to be measured.

Where a number of installation control assemblies are sited together, a testing facility is only necessary on one installation control assembly, provided that it is fitted to the assembly requiring the highest flow.

4.5 CONNECTIONS FOR OTHER SERVICES

4.5.1 General

The water supply to a sprinkler system shall be separate with no other connections except where it can be demonstrated to the appropriate authority that the maximum draw-off by other connected services would not decrease the performance or reliability of the sprinkler system.

Where a connection is to a town main or the supply is from a private source, the provisions of Clause 4.5.3 for hose reels shall apply. If other connections are necessary to comply with water supply authority requirements, any such connection shall be made upstream of the sprinkler system main stop valve and shall be fitted with separate isolating valves.

4.5.2 Combined sprinkler and hydrant water supply

The water supply for both automatic sprinkler and fire hydrant services within a property may be combined. In the case of buildings greater than two storeys in height where a combined system is used, the requirements of AS 2118.6 shall be met. In the case of

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building not exceeding two storeys in height where a combined system is used, the following criteria shall be met:

(a) The water supply is of sufficient capacity to provide the combined flow requirements for both sprinklers and hydrants.

(b) Ring mains incorporating isolating valves complying with AS 2419.1 for all combined sprinkler/hydrant systems that have external hydrants or hydrants that may be subject to damage.

Where ring mains are not used, an isolating valve shall be installed at the point of connection of any branch serving more than one hydrant.

(c) Piping shall be sized on the basis of the aggregate flow at any point in the system with a velocity not exceeding 4 m/s. For ring mains, the flow shall be taken in one direction only for velocity calculations.

NOTE: It is not intended that flow taken in one direction be applied to friction loss calculations.

(d) Where a tank is provided, the tank be compartmentalized to permit retention of at least half the supply when it is necessary to shut down for cleaning or repairs and—

(i) be of sufficient capacity to comply with the requirements of (a) above; or

(ii) have a capacity not less than 2/3 of the quantity of water required in (a) above, provided that the remainder is made up from a reliable source by an automatic inflow for the operational period required for sprinklers or hydrants, whichever is the more stringent.

(e) Where pumps are provided, the pumps shall comply with AS 2941 and Clauses 4.3.8 and 4.3.9 and—

(i) be of sufficient capacity to supply the requirements of sprinklers and hydrants simultaneously;

(ii) the number and arrangement of pumps to comply with the relevant requirements for the hazard class and of the water supply; and

(iii) have automatic starting in accordance with AS 2941; where remote manual start is required for fire hydrant operation, the manual start stations to be sealed in a manner which will ensure that any operation of the starting device is readily discernible, e.g., lead and wire seals, break-glass facilities or similar.

(f) Sprinkler and hydrant systems to comply with pressure limitations applicable to both systems.

NOTE: See AS 2118.6 for combined sprinkler and hydrant systems for installation in multi storey buildings. The requirements of AS 2118.6 do not apply to Clause 4.5 or 4.5.3.

4.5.3 Fire hose reel connections

4.5.3.1 General

Connections to sprinkler system water supplies are permitted for fire hose reels, provided the appropriate requirements of Clauses 4.5.3.2 to 4.5.3.4 are complied with. Such connections shall not exceed DN 50 and shall be provided with a stop valve suitably labelled and in close proximity to the point of connection with the supply pipe.

4.5.3.2 Town mains

Provided that the town main and the sprinkler supply pipe are not less than DN 100—

(a) a single pipe may be taken from the sprinkler supply pipe for fire hose reels; and

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(b) where the water supply comprises connections taken from more than one town main, connections for fire hose reels shall only be made between the point where the supplies are joined and the sprinkler system main stop valve.

4.5.3.3 Elevated private reservoirs, gravity tanks and automatic pumps

Any required connections to supply fire hose reels shall be made on the supply side of the sprinkler system main stop valve. In installations supplied from more than one of these sources, connections for fire hose reels are permitted to be made similarly to Clause 4.5.3.2(b).

4.5.3.4 Pressure tanks

Where a pressure tank forms the sole supply to an installation, hose reel connections are not permitted.

Where a pressure tank forms a second supply to the installation, a fire hose reel connection is permitted similarly to Clause 4.5.3.2(b).

4.5.4 Fire brigade booster connection

All sprinkler systems shall be fitted with a fire brigade booster connection to enable the fire brigade to pressurize or pump water into the system.

Fire brigade booster connections, with the exception of suction outlets, shall conform to the requirements of AS 2419.1. Fire brigade booster connections shall be adequately supported and located outside the building in a position that is readily accessible to fire brigade personnel.

A full way non-return valve shall be fitted downstream of the booster inlets together with any other fittings required by the water supply authority, and with capped hose connections suitable for use by the local fire brigade.

The number of inlets at the booster connection, up to a maximum of four, shall be sufficient to supply the requirements of the sprinkler system. The input at each inlet connection shall be based on the rate of 600 L/min.

The location or the enclosure, as applicable, for the fire brigade booster connection shall be marked with—

(a) the words ‘SPRINKLER BOOSTER CONNECTION’ in letters not less than 50 mm high, in a colour contrasting with that of the background; and

(b) the maximum allowable inlet pressure at the connection. NOTE: Attention is drawn to the need to ensure that a suction outlet is available in close proximity to the fire brigade booster connection.

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S E C T I O N 5 S P A C I N G A N D L O C A T I O N O F S P R I N K L E R S

5.1 SPACING OF SPRINKLERS

5.1.1 Standard sprinkler spacing

The maximum area of coverage per sprinkler and the maximum distance between sprinklers on range pipes and between adjacent rows of sprinklers shall be as specified for the class of hazard (see Clauses 9.4, 10.4 and 11.4 and Figure 5.1.1).

5.1.2 Special sprinkler spacing

The maximum area of coverage per sprinkler and the maximum distance between sprinklers on range pipes and between adjacent rows of sprinklers shall be as listed for the particular design requirements for the sprinkler. (See also Clause 1.3.26, and Clause 2.1.3.)

5.1.3 Staggered spacing

Where sprinklers are staggered, the arrangements shall be uniform. The maximum distance from the end sprinkler to the wall or partition in each alternate row shall be one-fourth of the design sprinkler spacing down the row; the spacing of the next sprinkler in the same row shall be three-fourths of the design spacing (see Figure 5.1.3).

5.2 MINIMUM DISTANCE BETWEEN SPRINKLERS

The minimum distance between standard sprinklers shall not be less than 2 m; and the minimum distance between Light Hazard sprinklers shall not be less than 2.5 m, except where intervening constructional features provide a satisfactory baffle or where special baffles are installed in order to prevent an operating sprinkler from wetting adjacent sprinklers.

The minimum distance between special sprinklers shall be as listed for the particular design requirements for the sprinkler.

Baffles shall be at least 200 mm wide × 150 mm deep and preferably be of sheet metal. They shall be located approximately midway between sprinklers and arranged to shield the actuating elements of sprinklers from the spray from adjacent sprinklers.

5.3 LOCATION OF SPRINKLERS (OTHER THAN SIDEWALL SPRINKLERS)

5.3.1 General

In addition to limitations specified for the maximum area coverage per sprinkler and the maximum distance between sprinklers (see Clause 5.1), sprinklers shall be located so that there will be minimal interference to the discharge pattern by structural members such as beams, columns, girders and trusses (see Clause 5.5) or any other obstructing feature such as ducting, piping, cable trays or light fittings. Sprinklers shall also be located at the appropriate distance below ceilings and roofs as required by Clause 5.3.3.

5.3.2 Walls and partitions

Except as provided for in Clause 5.1.3, the distance of sprinklers from walls or partitions shall be as specified for the appropriate hazard class (see Clauses 9.4.4, 10.4.5 or 11.3.

For open-joisted ceilings or where the roof has exposed common rafters (see Clause 13.23), the distances from walls and partitions referred to in Clause 9.4.4, 10.4.5 or 11.3 as appropriate, shall not exceed 1.5 m.

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FIGURE 5.1.1 STANDARD SPACING

Sprinklers shall be placed not more than 1.5 m from external walls where these are constructed of—

(a) combustible material;

(b) fibrous cement or metal, with combustible lining in either case; or

(c) metal (whether on wood or metal frame and with or without combustible lining) protected with a coating of bitumen, tar or pitch, or with material impregnated or treated with bitumen, tar or pitch.

Open-faced buildings shall have sprinklers not more than 1.5 m from the open face.

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NOTE: Illustration shows acceptable staggered arrangement for Ordinary Hazard where it is desired to space sprinklers more than 4.2 m apart on range pipes.

FIGURE 5.1.3 STAGGERED SPACING

5.3.3 Ceilings, roofs and underside of stairs

Unless specifically varied by a listed sprinkler data sheet, the following requirements apply to sprinklers located below ceilings, roofs and stairs.

(a) Sprinkler deflectors shall be parallel to any slope of the ceiling, roof or underside of stairs.

(b) Spacing measurements shall be taken horizontally.

(c) When fitted under a sloping surface that is greater than 1 in 3, a line of sprinklers shall be fitted at the apex unless there is a row of sprinklers at a radial distance not greater than 750 mm from the apex.

(d) Sprinklers shall not be recessed in sloping ceilings unless specifically manufactured for such mounting.

(e) Sprinklers shall be located not more than 300 mm below combustible or frangible ceilings or roofs.

(f) Sprinklers shall be located not more than 450 mm below ceilings or roofs containing no combustible material.

(g) For open joists and exposed common rafter construction, measurements shall be taken from the underside of joists or rafters.

(h) Deflectors shall be not more than 150 mm below joists of open-joist ceilings.

(i) Measurements in Items (e) and (f) above for arched ceilings or ceilings of irregular shape shall be taken from the highest point in the ceiling.

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5.4 SPACING AND LOCATION OF SIDEWALL SPRINKLERS

5.4.1 General

The following requirements shall apply to the spacing and location of sidewall sprinklers:

(a) The sprinklers (see Clauses 1.3.30(f)) shall be mounted with their deflectors not more than 150 mm and not less than 100 mm from the ceiling.

(b) The centre-line of the sprinklers shall be not less than 50 mm and not more than 150 mm from the wall face on which they are mounted.

(c) There shall be no obstruction at the ceiling within an area extending along the wall 1 m on each side of a sprinkler and 1.8 m at right angles to the wall.

(d) Beams on any boundary of this area shall not exceed a depth of 100 mm.

(e) If sprinklers are mounted closer to beams than the distances specified in Clause 5.5.3, the bays formed shall be separately protected.

5.4.2 Spacing of special sidewall sprinklers

The maximum area of coverage per sprinkler and the maximum and minimum distances between sprinklers on range pipes and between adjacent rows of sprinklers shall be listed for the particular design requirements for the sprinkler

5.4.3 Maximum spacing of sidewall sprinklers

The spacing of sidewall sprinklers along the walls and from end walls shall be appropriate to the hazard class (see Clause 9.4.4 or 10.4.4).

5.4.4 Distance between rows of sprinklers

The distance between rows of sprinklers shall comply with the following requirements:

(a) Rooms not exceeding 3.7 m in width shall have a minimum of one row of sprinklers along the length of the room.

(b) Rooms exceeding 3.7 m but not exceeding 7.4 m in width shall have one row of sprinklers at each side along the length of the room.

(c) In rooms exceeding 7.4 m in width, conventional, spray or ceiling type sprinklers shall be provided centrally positioned under the ceiling to supplement the sidewall sprinklers.

In rooms exceeding 9.2 m in length (Light Hazard) or 7.4 m in length (Ordinary Hazard), the sprinklers shall be regularly staggered so that they face midway between the sprinklers on the opposing wall.

5.5 OBSTRUCTIONS TO SPRINKLER DISCHARGE

5.5.1 General

Structural members such as beams, joists and columns, together with other features of the building such as ductwork, pipes, cable trays, light fittings and bulkheads in close proximity to the ceiling shall be treated as obstructions to sprinkler discharge. Unless specifically varied by a listed sprinkler data sheet, the requirements of Clauses 5.5.2 to 5.5.9 shall apply:

5.5.2 Standard upright and pendent sprinklers

Where deflectors of sprinklers are above the level of the bottom of obstructions, the sprinklers shall be at such distances from the obstruction that undue interference with the sprinkler discharge pattern is avoided.

The clearances required from obstructions are dependent upon the maximum coverage of the sprinkler being used, and are shown in Figure 5.5.2 and Table 5.5.2.

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Where the depth of a beam (see Figure 5.5.2(B)) exceeds 300 mm (non-fire-resisting ceilings) or 450 mm (fire-resisting ceilings) and it is impracticable to position sprinklers at the required distance from the side of the beam, the beam shall be treated as a wall insofar as the sprinklers in the adjoining bay are concerned. In no case shall the sprinkler spacing exceed that specified in Clause 5.1.

Where the depth of beams (or joists) is such that the dimensions specified in Table 5.5.2 cannot be complied with and the beams (or joists) are spaced closer than 1.8 m measured from centre-to-centre of the beam, the sprinklers shall be stagger-spaced (see Clause 5.1.3).

For columns causing obstruction to sprinkler discharge, see Clause 5.5.4 and Figure 5.5.4.

FIGURE 5.5.2 CLEARANCES FROM OBSTRUCTIONS—STANDARD UPRIGHT AND PENDENT SPRINKLERS

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TABLE 5.5.2

CLEARANCES FROM OBSTRUCTIONS—STANDARD SPRINKLERS

Dimension B—Maximum height of deflector above obstruction/beam Dimension A Conventional

pendent Conventional

upright 12 m2

SSU/SSP 21 m2

SSU/SSP

100 N/A N/A 0 0

200 N/A −20 20 0

300 N/A −10 40 15

400 N/A 0 60 30

500 N/A 15 85 45

600 N/A 30 115 60

700 N/A 45 145 85

800 N/A 60 180 110

900 N/A 80 215 140

1000 −200 100 250 170

1100 −185 120 290 200

1200 −170 140 320 230

1300 −145 165 370 265

1400 −120 190 410 300

1500 −75 225 450 335

1600 −30 260 — 370

1700 70 325 — 410

1800 170 390 — —

NOTE: Where the sprinkler deflector is required to be below the obstruction, dimension B is shown as negative (−ve)

5.5.3 Standard sidewall sprinklers

Where the centre-line of sidewall sprinklers is above the level of the bottom of obstructions, the sprinklers shall be at such distances from the obstruction that interference with the sprinkler discharge pattern is avoided.

The clearances required from obstructions are dependent upon the maximum coverage of the sprinkler being used and are shown in Figure 5.5.3 and Table 5.5.3 for standard sidewall sprinklers.

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FIGURE 5.5.3 CLEARANCES FROM OBSTRUCTIONS—STANDARD SIDEWALL SPRINKLERS

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TABLE 5.5.3

CLEARANCES FROM OBSTRUCTIONS FOR STANDARD SIDEWALL SPRINKLERS

Dimension B (Max.) Dimension A (Min) Normal to wall Parallel to wall

100 0 0

150 0 25

200 0 35

300 0 60

400 0 80

500 0 100

600 0 120

700 0 140

800 0 160

900 0 185

1000 0 205

1100 0 225

1200 0 245

1300 15 265

1400 25 285

1500 40 305

1600 55 325

1700 75 345

1800 90 365

1900 110 385

2000 135 405

2100 160 430

2200 185 450

2300 220 —

2400 255 —

2500 290 —

2600 350 —

5.5.4 Standard upright and pendent sprinklers near columns

Where individual sprinklers are located near columns, the following spacing and location requirements shall apply as appropriate (see Figure 5.5.4):

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(a) For 15 mm and greater nominal orifice size standard sprinklers—if A ≤3B or 3C whichever is greater then D ≤ S/2.

(b) For 10 mm standard sprinklers—if A ≤ 3.5B or 3.5C (whichever is greater) then D ≤ S/2.

S = the allowable spacing between sprinklers.

FIGURE 5.5.4 STANDARD UPRIGHT AND PENDENT SPRINKLER DISTANCES FROM COLUMNS

5.5.5 Standard sidewall sprinklers near columns

Where sidewall sprinklers are located near columns, the following spacing and location requirements shall apply (see Figure 5.5.5): Dimension A shall be greater than 3B or 3C (whichever is greater) but not less than 600 mm.

FIGURE 5.5.5 STANDARD SIDEWALL SPRINKLER DISTANCES FROM COLUMNS

5.5.6 Roof trusses

Sprinklers shall be not less than 300 mm laterally from truss members that are 100 mm nominal or less in width. Where truss member widths exceed 100 mm, the sprinklers shall be not less than a radial distance from the member of 4 times the height or width of the truss member, whichever is the greater.

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5.5.7 Clear space below sprinklers

Except as permitted in Clause 5.5.8, Clause 5.6.2 and Clause 11.1.3.3(b), a clear space not less than 500 mm shall always be maintained below the level of the sprinkler deflectors throughout the compartment. For high-stack combustible storage, a clear space not less than 1 m shall be maintained below the level of the sprinkler deflectors throughout the compartment. Where sloping ceilings or roofs are concerned, stored goods may follow the slope, provided that the above clearances are maintained.

For rolling storage cabinets, a clear space below the level of sprinkler deflectors may be reduced to not less than 100 mm provided the maximum area coverage is reduced to 9 m2 per sprinkler.

5.5.8 Obstructions in clear space

Where there are obstructions such as girders, ducting, cable trays, pipe racks and continuous lighting less than 800 mm and more than 300 mm wide that are either wholly or partly within the required clear space, specified in Clause 5.5.7, there shall be a line of sprinklers located either side of the centre-line of the obstruction and at no more than half the allowable design spacing from the centre-line of the obstruction. Where the obstruction is less than 300 mm wide, the radial distance from the sprinkler deflector to the nearest point of the obstruction shall be not less than 4 times the height or width of the obstruction, whichever is the greater.

5.5.9 Obstructions under sprinklers

5.5.9.1 General

Where obstructions below sprinklers are such that the operation of sprinklers could be delayed or effective distribution of water from the sprinklers could be impaired, additional sprinklers shall be mounted below such obstructions in accordance with Clauses 5.5.9.2 to 5.5.9.7.

5.5.9.2 Overhead platforms

Sprinklers shall be installed below internal overhead platforms, heating panels, galleries, walkways, stagings, stairs and stairways and chutes exceeding 800 mm wide and closer than 150 mm to adjacent walls.

Where the clearance from adjacent walls exceeds 150 mm, sprinklers shall be fitted below any such structure that exceeds 1 m in width.

5.5.9.3 Ducts, bulkheads and beams

Sprinklers shall be installed under rectangular ducts, bulkheads and beams exceeding 800 mm in width and under circular ducts exceeding 1 m in diameter. Where there is at least 150 mm clearance from adjacent walls, the width without protection may be 1 m and 1.2 m, respectively.

Where a duct is erected with the top of the duct less than 500 mm below the ceiling or roof, it shall be regarded as a beam and the requirements of Clauses 5.5.2 or 5.5.3 shall apply.

5.5.9.4 Suspended ceilings

Sprinklers shall be installed below suspended ceilings, e.g., in connection with diffused lighting, except where the ceiling construction does not impair the effective water distribution from the sprinklers above (see also Clause 5.5.9.5).

5.5.9.5 Suspended open grid ceilings

Sprinkler protection shall be provided above and below suspended open grid ceilings to the appropriate hazard classification. Sprinklers may be omitted from below open grid ceilings with the appropriate hazard classification installed above the grid, provided that—

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(a) the minimum dimension of the openings in the grid is not less than 25 mm or the vertical thickness of the suspended ceiling, whichever is the greater;

(b) suspended open grid ceilings in Light Hazard and Ordinary Hazard occupancies do not involve storage areas;

(c) the open area of the ceiling grid is not less than 70% of the total plan area;

(d) where services are installed within the grid ceiling, e.g., light fittings, these features do not reduce the open area to less than 60%;

(e) only spray sprinklers are used;

(f) the vertical distance between sprinkler deflectors and the top of the ceiling grid is not less than 800 mm; and

(g) wherever obstructions above the ceiling grid would cause interference to the sprinkler discharge pattern, the sprinkler is located in accordance with the provisions of Section 5.

5.5.9.6 Hoods over papermaking machines

The underside of hoods or shields over the dry ends of papermaking machines shall be sprinkler protected. Sidewall sprinklers (see Clause 5.4) may be used for this purpose.

5.5.9.7 Storage racks

Sprinklers shall be fitted in such positions as to afford efficient protection to goods stored in racks (see Clause 11.1.3).

5.5.9.8 Storage fixtures of solid and slatted shelved construction

Storage fixtures wider than 2 m shall be fitted with sprinklers at each shelf level.

Storage racks and fixtures wider than 1.2 m but not wider than 2 m shall be—

(a) fitted with sprinklers; or

(b) fitted with bulkheads that shall divide the fixture into areas not exceeding 9 m2, with the distance between bulkheads not exceeding 6 m, provided that the total storage height does not exceed the values given in Table 11.1.3.2(B).

Such bulkheads shall be tight partitions extending from front to rear faces and from top to bottom of the storage spaces. They shall be constructed from one of the following materials:

(i) 15 mm tongued and grooved timber.

(ii) 13 mm hardboard.

(iii) 16 mm chipboard.

(iv) 7 mm flexible fibre cement sheeting.

(v) 0.6 mm steel sheet.

5.6 CONCEALED SPACES

5.6.1 General

Concealed spaces between ceilings and roofs or floors above, and below false floors, shall be fitted with sprinklers. The following spaces are exempt from the requirements of this Clause:

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(a) Concealed spaces less than 200 mm in depth measured from the top of the ceiling material or the floor to the underside of the structure above.

(b) Concealed spaces bounded entirely by non-combustible construction, not communicating with other sprinkler protected spaces, not used for storage of any kind and containing only—

(i) lighting, power and data cables to AS/NZS 3000, in groups of not more than 15 cables or in cable trays containing not more than 15 cables, where each cable group or cable tray shall have a clear space of at least 4 times the width of the cable group or cable tray;

(ii) piping containing non-flammable fluids;

(iii) metal ducting with insulation and flexible connections complying with the requirements of AS 4254; or

(iv) non-combustible insulation on piping.

5.6.2 Protection criteria

Where sprinkler protection is required in concealed spaces, the sprinklers shall be fast response, Light Hazard spray sprinklers in accordance with Light Hazard requirements (see Section 9) except that the provisions contained in Clause 5.7 need not apply. The requirements of Clause 5.5 need not apply except where it is impractical to position sprinklers sufficiently from ductwork or beams in which case, they shall be treated as a wall.

Concealed spaces exceeding 200 mm but not greater than 800 mm in depth and not qualifying under Clause 5.6.1(b) shall be fitted with—

(a) fire and draft stops provided at intervals not exceeding 15 m in each direction; or

(b) 42 m2 skeleton spacing of fast response, Light Hazard spray sprinklers, spaced at maximum of 6.0 m × 7.0 m.

Concealed spaces used intermittently or permanently as storage areas shall be protected by sprinklers suitable for and in accordance with the appropriate hazard classification.

5.6.3 Hydraulic design—concealed spaces

Where sprinkler protection is required in concealed spaces and under floor spaces to satisfy the requirements of Clause 5.6.1, it shall be hydraulically designed in accordance with the requirements of Section 9.

5.6.4 Deformable ceilings

All concealed spaces above ceilings constructed of materials that will readily deform or collapse under fire conditions (e.g., vinyl, acrylic, polyurethane and polystyrene plastics), shall be sprinkler protected in accordance with the hazard classification of the area below. Sprinkler protection may be omitted from below the ceiling only where the ceiling is designed to deform or collapse.

5.7 SPECIAL CONSIDERATIONS (SUPPLEMENTARY PROTECTION) FOR REQUIRED SPRINKLER SYSTEMS.

5.7.1 Machinery pits and production lines

Machinery pits and the underside of production lines, where waste may collect, shall be protected.

5.7.2 Hoists, lift shafts, building services shafts and enclosed chutes

Sprinklers shall be installed in all hoists, lift shafts, service shafts and chutes that are inside or in communication with buildings. The positioning of the sprinklers shall be as follows:

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(a) Hoists, lift shafts and sheave rooms Sprinklers shall be installed in the top and base of each hoist and lift shaft. Sprinklers installed in lift shafts and sheave rooms shall be protected by stout metal guards and shall have a temperature rating of not less than 100°C in accordance with the appropriate part of AS 1735.

(b) Building services shafts Shafts housing air-handling ducts and other building services that are not sealed at each floor level and are provided with access panels or doors shall have sprinklers fitted at vertical intervals of 15 m in addition to that at the head of the shaft.

(c) Chutes Chutes for disposal of refuse, soiled linen, and similar, shall have a sprinkler in the head of each chute. Chutes in buildings exceeding two storeys in height shall have a sprinkler fitted at each alternate level in addition to that at the head of the chute.

All sprinklers installed in chutes and shafts shall be protected from mechanical damage and shall be fitted, where necessary, with suitable baffles in order to prevent the first operating sprinkler from wetting the lower sprinklers.

5.7.3 Elevators, rope or strap races, exhaust ducts, gearing boxes and dust receivers

A sprinkler shall be fitted in the box at the top of every elevator. Pneumatic type elevators are exempt from this requirement as well as those that comprise a slow moving endless chain fitted with rings, loops or forks, capable of functioning only when the elevator is full. The sprinkler in each case shall be so placed as to command the head and both legs or shafts of the elevator.

Sprinklers shall be fitted internally in all rope or strap races, enclosed belt or shaft machine drives and gearing box compartments.

Where exhaust fans are installed within ducts conveying dust or refuse, a sprinkler shall be fitted inside the duct immediately downstream of the fan.

To prevent obstruction and mechanical damage, the sprinkler shall be recessed within a purpose-built metal box mounted on the duct.

Sprinklers shall not be installed on the underside of the ducts.

Sprinklers shall be fitted in dust cyclones, collection chambers and boxes where these are—

(a) housed within the protected building;

(b) erected outside and directly above the protected building unless the roof is of non-combustible construction; or

(c) external to but connected with and closely adjacent to the protected buildings.

Where dust cyclones, collection chambers and boxes are erected above non-combustible roofs or where they are situated remote from the protected buildings, at least one sprinkler shall be fitted inside the trunking where it leaves the protected building.

5.7.4 Corn, rice, provender and oil mills

Sprinklers shall be fitted in corn, rice, provender and oil mills as follows:

(a) Sprinklers shall be fitted not more than 3 m apart inside all dust trunks that are more than 30° from the vertical and constructed of combustible materials.

(b) A sprinkler shall be fitted at the head of every dust trunk.

Where centrifugals or similar machines are placed one above another in tiers as shown in Figure 5.7.4 and are less than 1 m from each other, sprinklers shall be fitted in the spaces as shown.

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FIGURE 5.7.4 MACHINES IN TIERS

5.7.5 Bins and silos

All bins and silos of combustible construction with a plan area in excess of 9 m2, used for the storage of flour, bran, or other similar material that has undergone any process of reduction (in such premises as flour mills, granaries, oil mills or distilleries) or for the storage of sawdust, wood flour, pulverized coal and similar easily ignitable materials that can be extinguished by water shall be internally protected by sprinklers on the basis of one sprinkler per 9 m2 of the bin or silo area (see also Clause 10.4.3).

NOTE: If the bin or silo contains materials that will swell when wet and are likely to incur the risk of bursting, exemption from this Clause may be allowed (see Clause 3.1.2(b)).

5.7.6 Escalators

Sprinklers shall be fitted under the escalator and in the escalator boot and motor space. Where limited space prevents this, sprinklers shall be fitted in any surrounding ceiling or floor space immediately adjacent to the escalator. These sprinklers shall be fitted regardless of the provisions of Clauses 5.7.1 and 5.7.2.

5.7.7 Canopies

Sprinklers shall be installed under all canopies where goods are stored or handled or where the dividing wall between the canopy and the building is of non-combustible construction. In the case of canopies of non-combustible construction less than 2.5 m in width over pedestrian walkways, or any width over public footpaths, sprinklers may be omitted.

5.7.8 Roof overhang

Any roof overhang exceeding 1.5 m in width shall be treated as a canopy. NOTE: Roof overhangs that extend from sprinkler protected areas and project over the roof of adjoining sprinkler-protected areas and are not opposed to an exposure hazard (see Clause 3.1) need not be protected.

5.7.9 Exterior docks and platforms

Sprinklers shall be installed under exterior docks and loading platforms of wholly or partially combustible construction. Where such spaces are completely sealed against the accumulation of debris, this requirement does not apply.

5.7.10 Covered balconies

Portions of covered balconies that exceed 6 m2 floor area and have a depth in excess of 2 m shall be sprinkler protected.

5.7.11 Enclosed paint lines, drying ovens, drying enclosures

Sprinkler protection shall be provided inside enclosed paint lines, drying ovens and drying enclosures. Sidewall sprinklers (see Clause 5.4) may be used for this purpose.

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NOTE: Where practicable, sprinklers in ambient temperatures above 70°C should be on a dry system, or the feed pipes thereto should rise up to the sprinklers or groups of sprinklers so as to restrict the thermal circulation of the heated water in the pipes.

5.7.12 Spray booths

Sprinkler protection shall be provided inside spray booths and connected exhaust ducts.

Sprinklers installed within spray booths and connected exhaust ducts shall be protected against the accumulation of residue from spraying operations by a liberal coating of petroleum jelly and paper bags, which shall be cleaned off and renewed as often as may be necessary to prevent the formation of a hard deposit on the sprinklers and so preserve their efficiency. Plastic bags or other protective covering shall not be used for this purpose.

5.7.13 Oil and flammable liquid hazards

Sprinkler protection shall be provided for all oil and flammable liquid hazards. NOTES: 1 Examples of such hazards include dip tanks and oil-filled electrical transformers. 2 It is recognized that in certain cases modified or supplementary protection may be required

where extensive storage, handling or processing equipment such as large dip tanks, varnish kettles, reactors or oil-filled electrical transformers are employed. In these cases medium or high-velocity sprayers or other arrangements may be employed in lieu of or in conjunction with sprinklers, provided that adequate water supplies are available.

3 Electricity supply authorities may not permit sprinklers in the vicinity of transformers installed on private property.

5.7.14 Commercial type cooking equipment and associated ventilation systems

Sprinkler protection shall be provided under hoods, and above cooking equipment and associated ventilation systems designed to carry away grease-laden vapours. Sprinklers shall be located not more than 3.6 m apart under hoods, 4 m apart in horizontal ducts, and at the head of all rising ducts. The first sprinkler in a horizontal duct shall be installed adjacent to the duct entrance (see Figures 5.7.14 (A) and (B)).

The system shall be designed so that a cooking surface fire will operate the sprinklers protecting the cooking surface prior to or simultaneously with those protecting the connected ductwork. This may be accomplished by installing sprinklers in the ducts one temperature rating higher than those protecting the cooking surface, but in any event, not less than 182°C.

Deep fat fryers shall have one spray pattern sprinkler centred longitudinally over each single fryer or pair of fryers. Such sprinklers shall operate at not less than 200 kPa and shall have their frames parallel to the front edge of the hood. Their deflectors shall be located at least 25 mm below the lower edge of the hood and not less than 600 mm nor more than 1.2 m above and parallel to the cooking surface. Pipework and fittings shall be stainless steel and sprinklers shall be chromium plated.

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NOTE: Multiple ducts from canopy need not be sprinkler protected if the common plenum duct is used.

FIGURE 5.7.14(A) TYPICAL KITCHEN COOKING ARRANGEMENT—LOCATION OF SPRINKLERS

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Sprinklers protecting the surrounding area shall be arranged so that they do not cause water to fall into deep fat fryers. Where this is accomplished by the provision of a shield or unducted hood over the deep fat fryer, such shield or hood shall be placed above the shroud protecting the deep fat fryer and shall be so located that it will not interfere with sprinkler discharge.

5.7.15 Air-handling plant

5.7.15.1 Location of sprinklers

In air-handling plants sprinklers shall be located throughout—

(a) the return air/fresh air plenum;

(b) the chambers on each side of any filter bank; and

(c) the fan/motor chamber. NOTE: See Clause 6.5 for information regarding temperature ratings of sprinklers.

5.7.15.2 Exceptions

Sprinklers may be omitted from air-handling plants that have an external plan area less than 12 m2 and an external height less than 2 m.

Sprinklers shall not be installed in fan/motor chambers through which spill air is designed to pass under fire conditions in accordance with AS/NZS 1668.1.

5.7.16 Computer and other electronic equipment areas

5.7.16.1 Location of sprinklers

Sprinkler protection shall be provided in areas where computers or other electronic equipment are installed.

5.7.16.2 Raised floor spaces

The space beneath any raised floor shall be treated in accordance with Clause 5.6.1.

5.7.17 Cupboards and wardrobes

Built-in cupboards and wardrobes for Light and Ordinary Hazard occupancies where the floor area does not exceed 2.5 m2, the walls and ceilings are lined with non-combustible materials and are not used for the storage of flammable liquids may have sprinklers omitted. Sprinklers in the adjoining room shall be positioned such that they would cover the area of the cupboard/wardrobe if the door was in the open position.

5.7.18 Film and television production studios

Sprinklers shall be fitted on the underside of overhead platforms or walkways including those for lighting or other equipment, whether slatted or not, together with stairs thereto, if they exceed 800 mm in width, provided that this shall not apply to temporary platforms in connection with sets.

5.7.19 Theatres and music halls (protection on the stage side of the proscenium wall)

In addition to the normal sprinkler protection of the roof, sprinklers shall be placed under the gridiron, under the flies, under the stage and in every portion on the stage side of the proscenium wall.

Where the provision of a line of open drenchers or open sprinklers on a fixed fire curtain is required, the control assemblies shall be of the quick-opening type and shall be located in a readily accessible position. Where the water supply to these open drenchers or sprinklers is taken from the sprinkler system, the flow and pressure requirements shall be added to the normal system requirements.

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5.7.20 Cold chambers

5.7.20.1 General

Wet type sprinkler systems may be used to protect cold chambers where the ambient temperature cannot fall below 4OC and the temperature conditions in the area where the piping is installed are such that there is no danger at any time of the water in the pipes freezing.

Dry pendent sprinklers shall be installed in air-circulating system plenums formed by one or more false ceilings within the cold chamber. NOTE: Where practicable, sprinkler piping should be located in normal temperature conditions above the cold chamber with dry pendent sprinklers connected thereto penetrating into the cold chamber.

Air circulation fans shall be closed down automatically on operation of the sprinkler system.

5.7.20.2 Piping within the cold chamber

The following special conditions shall apply where it is necessary to install the piping within the cold chamber, or where it is desired to house the sprinkler piping within a single small cold chamber:

(a) The sprinkler installation in the cool room shall be of the permanent dry type and the maximum number of sprinklers controlled by one dry valve shall not exceed 50. These groups of 50 sprinklers may be installed as tail-end dry systems on the basis of at least one control assembly (wet, dry or alternate wet and dry, as circumstances dictate) for each five groups.

Each tail-end system shall be controlled by a subsidiary stop valve (see Clause 8.2.4) and shall include either a water flow alarm switch or an electric alarm pressure switch (see Clause 8.13.5) to indicate the particular Section that is operating. These sectional warning systems are additional to the water motor alarm on the main control assembly. Where there is a series of tail-end systems and one main control assembly operating on the dry or alternate wet and dry principle, care needs to be taken to ensure that the air/gas pressure on the tail-end system is maintained at not less than the air pressure in the system between the control assembly and the tail-end dry valves.

Differential dry valves used in tail-end systems connected to an installation operating on the dry or alternate wet and dry principle shall be suitably modified to retain air pressure in the system piping between the main control assembly and the underside of the tail-end dry valves.

(b) Sprinklers installed in an air circulation plenum formed by a false ceiling within the cold chamber may be disregarded when determining the maximum number of sprinklers required under Item (a) above if the sprinklers are fed from the piping feeding the sprinklers in the cold chamber.

(c) The air supply for charging the sprinkler system shall be taken from the cold chamber, from the freezers of lowest temperature or through a chemical dehydrator.

Compressed nitrogen gas in cylinders may be used as a substitute for air; provided a pressure-reducing valve is used to reduce the gas pressure to not more than 800 kPa to avoid over-pressurizing the system piping.

(d) Piping joints shall be of a high standard of gas-tightness.

(e) The system shall be provided with a low air/gas pressure alarm.

(f) Dry pipe valves shall be housed outside the cold chamber in areas where the temperature is maintained above 4°C. Where valves are normally provided with a

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liquid seal, because of the problem of evaporation and possible ice formation in the piping, the sealing medium shall be a fluid such as propylene glycol.

(g) All piping downstream of the dry valve shall be installed above ground such that it can be readily dismantled and reinstated to permit thorough purging of moisture after operation.

Pipe jointing and hangers shall permit easy removal of the piping and an inspection point shall be provided at the position of entry into the cold chamber. Changes of direction shall be made by using tees with one branch sealed off instead of elbows. Pipes shall be sloped to drain (see Clause 7.4).

(h) Notwithstanding the requirements of Clause 2.1.2.4, sprinklers may be installed in either the upright or the pendent position, having regard to the necessity for the sprinkler system to be dismantled for drying out after each operation.

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S E C T I O N 6 S P R I N K L E R S , S P R A Y E R S A N D M U L T I P L E C O N T R O L S

6.1 GENERAL

Sprinklers shall not be altered in any respect nor have any type of ornamentation or coatings applied after leaving the production factory except as permitted by Clauses 5.7.12 and 6.8.

6.2 TYPES OF SPRINKLERS, SPRAYERS AND MULTIPLE CONTROLS

6.2.1 Standard sprinklers

Sprinklers shall comply with the requirements of AS 4118.1.1. Systems designed in accordance with Sections 9, 10 and 11, shall use standard sprinklers.

Standard sprinklers consist of the following (see Clause 1.3.30):

(a) Conventional sprinklers.

(b) Spray sprinklers .

(c) Flush sprinklers.

(d) Recessed sprinklers.

(e) Concealed sprinklers.

(f) Sidewall sprinklers .

(g) Dry pendent and dry sidewall sprinklers .

(h) Dry upright sprinklers .

(i) Enlarged orifice sprinklers.

(j) Large and extra large orifice sprinklers.

(k) Control mode sprinklers, identified by K factors, other than extended coverage and large drop sprinklers.

6.2.2 Special sprinklers

Special sprinklers are listed sprinklers other than those types listed in AS 4118.1.1. Systems incorporating special sprinklers shall be designed in accordance with Clause 2.1.3 (see Clause 1.3.26).

Special sprinklers include the following (see Clause 1.3.26): (a) Extended coverage sprinklers. (b) Control mode special application sprinklers (large drop sprinkler). (c) Suppression mode sprinklers (early suppression fast response sprinklers). (d) Residential sprinklers.

6.2.3 Sprayers Sprayers consist of the following (see Clause 1.3.28):

(a) Medium-velocity sprayers. (b) High-velocity sprayers.

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C6.2.3 Sprayers have directional discharge characteristics to provide direct impingement onto the protected surface and are available with cone angles ranging from 40° to 180°. A solid discharge cone is produced from the sprayer by either internal swirl vanes, tangential velocity swirl, or single orifice and deflector, with the minimum spray discharge pressures ranging from 150 kPa to 350 kPa, thus providing the higher water discharge velocities.

Sprayers in an installation shall be medium- or high-velocity type. Medium- and high-velocity sprinklers are special purpose sprayers for use in water spray systems, which may or may not form part of sprinkler systems intended for the extinguishing or controlling of fires involving flammable liquids and for the cooling of storage tanks, process plant and exposed structural steel work against heat from an exposure fire.

6.2.4 Multiple controls

Multiple controls shall be selected in accordance with their listing (see Clause 1.3.20).

C6.2.4 Multiple controls are used in systems with medium-velocity or high-velocity sprayers of the ‘open’ type in circumstances where it is required to operate small groups of sprayers simultaneously. They are also used in connection with bypass piping for alarm purposes. The controls are made in various sizes relevant to the diameter of the valve and the number of sprayers that are to be fed therefrom. The sizes range from 20 mm to 80 mm.

6.3 HYDRAULIC CHARACTERISTICS OF STANDARD SPRINKLERS

Standard sprinklers shall have minimum hydraulic characteristics as detailed in Table 6.3.

TABLE 6.3

MINIMUM HYDRAULIC CHARACTERISTICS OF SPRINKLERS

Minimum characteristics

K factor (K = Q/√ P) (see Note 3) Flow L/min Pressure kPa

Light Hazard 5.7 ± 5% 48 (see Note 1)

Ordinary Hazard 8.0 ± 5% 60 (see Note 1)

High Hazard As determined and selected by hydraulic analysis but not less than 8.0 ± 5%

(see Note 2) 50

NOTES: 1 Pressure corresponding to flow.

2 Flow as determined by pressure.

3 See Clause 1.4.15 for sprinkler K factor.

Large orifice sprinklers shall be spray sprinklers and typically have nominal K factors of 16.0 ± 5%, 20.0 ± 5%, 24.0 ± 5% or 36.0 ± 5% (see Clause 12.11.2 for application of K factors for dry pendent or upright sprinklers).

6.4 APPLICATION OF SPRINKLER TYPES

The types of sprinkler for the appropriate hazard class shall be limited to those nominated in Clauses 9.4.1, 10.4.1 and 11.4.1.1 except as permitted in Clauses 9.4.5 and 10.4.6.

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6.5 TEMPERATURE RATINGS The temperature ratings chosen shall be not less than 30°C above the highest anticipated temperature conditions except under the following circumstances :

(a) In locations that are directly exposed to the sun, such as— (i) under glazing; (ii) under translucent plastics; (iii) in uninsulated metal roofs; (iv) in unventilated concealed spaces; and (v) in show windows on external walls

NOTE: Under glazing, translucent plastics and uninsulated metal roofs, in unventilated concealed spaces and show windows on external walls, and in other locations that are directly exposed to the sun, it may be necessary to install sprinklers with a temperature rating between 79°C and 100°C.

(b) In High Hazard systems protecting high-stack storage, sprinklers having a minimum nominal temperature rating of 141°C shall be used at the roof or ceiling, except where in the case of special sprinklers, the listing recommends an alternative temperature rating.

(c) Where high-temperature sprinklers are installed within drying ovens or hoods over papermaking machines and the like (see Clauses 5.7.11 and 5.5.9.6) sprinklers at the ceiling or roof immediately over and to a distance of 3 m beyond the boundary of such structures shall be of the same temperature rating, subject to a maximum of 141°C.

6.6 COLOUR CODING The colour code specified in AS 4118.1.1 shall be used to distinguish sprinklers of different nominal temperature ratings.

6.7 ANTI-CORROSION TREATMENT OF SPRINKLERS

Sprinklers used in bleach, dye and textile print works, alkali plants, organic fertilizer plants, foundries, pickle and vinegar works, electroplating and galvanizing works, paper mills, tanneries, and in any other premises or portions of premises where corrosive vapours are prevalent, shall have corrosion-resistant coatings or shall be coated twice with a petroleum jelly. The first coat shall be applied before installation and the second shall be applied after installation. NOTE: Coatings need to be renewed at periodic intervals as may be necessary but only after the existing coatings have been thoroughly wiped off. For glass bulb-type sprinklers, the anti-corrosion treatment need only be applied to the body and yoke.

6.8 SPRINKLER GUARDS

Where sprinklers are installed in locations where they are likely to suffer mechanical damage, they shall be fitted with metal guards. Guards shall be designed so as not to interfere with the normal spray pattern of the sprinkler. Guards shall not be used with flush, recessed or concealed-type sprinklers.

6.9 ESCUTCHEON PLATE ASSEMBLIES

Escutcheon plate assemblies fitted to sprinklers shall be of metal and securely attached so that they cannot slip down and adversely affect activation or the water discharge pattern of sprinklers.

Recessed escutcheon plate assemblies shall only be used with sprinklers that have been listed for such mounting (see Clause 6.2.1(d)).

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C6.9 Non-metallic escutcheon plate assemblies may deteriorate with age or distort during fire conditions and interfere with the effective operation of the sprinkler.

6.10 PROTECTION AGAINST FROST

Sprinklers shall not be wrapped or enclosed in any material for protection against frost.

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S E C T I O N 7 P I P I N G

7.1 PIPE AND PIPE FITTINGS

All pipes and pipe fittings in a sprinkler installation shall be new and shall comply with the requirements of AS 4118.2.1.

7.2 HYDRAULIC TEST PRESSURE

All new installations, trunk mains and water supply connections shall be capable of withstanding an hydraulic test pressure as specified in Clause 7.8.3.

7.3 PIPING IN NON-SPRINKLER-PROTECTED BUILDINGS

With the exception of concealed spaces not requiring protection as permitted in Clause 5.6, and fire-isolated exits, sprinkler piping shall not pass through buildings or areas not protected by sprinklers unless it is enclosed by a construction suitable to resist fire exposure for a period not less than the required duration of water supply applicable to the system; namely, Light Hazard, Ordinary Hazard or High Hazard.

7.4 DRAINAGE

7.4.1 Wet system piping

In basements and other areas where sprinkler piping is below the installation drain valve and in trapped sections of distribution piping, auxiliary drain valves of the following minimum sizes shall be provided:

(a) For pipes up to DN 50...................... ..............................................................20 mm.

(b) For DN 65 pipes .................. ............................................................…...........25 mm.

(c) ©For pipes larger than DN 65 .............. .................................…….........….....32 mm. NOTE: Distribution piping should, where possible, be arranged to enable the installation to be drained using the drain valve at the installation control assembly. The installation drain valve should be not less than DN 50 for Ordinary Hazard and High Hazard systems and not less than DN 40 for Light Hazard systems.

7.4.2 Dry or alternate wet and dry system piping

Sprinklers forming part of dry or alternate wet and dry systems shall be so installed that the system can be thoroughly drained. Range piping shall have a slope of not less than 4 mm in 1 m, and distribution piping shall have a slope of not less than 2 mm in 1 m.

NOTE: Piping in all systems, including piping in wet systems, should, where possible, be arranged to drain to the installation drain valve which should be not less than DN 50 for Ordinary Hazard and High Hazard systems and not less than DN 40 for Light Hazard systems.

C7.4 Having an effective drainage facility does not improve the performance of the system; however, it is desirable when servicing a wet pipe installation and essential for dry and alternate wet and dry installations. Water damage can easily occur when cutting installation piping that is still charged with water when carrying out repairs or alterations.

7.5 FLEXIBLE TUBE ASSEMBLIES

Flexible tube assemblies for the connection of individual sprinklers to rigid pipework above suspended ceilings shall comply with the following:

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(a) The minimum size shall be—

(i) DN 20 for Light Hazard; and

(ii) DN 25 for Ordinary and High Hazard.

(b) The flexible tube shall be of metal construction and shall be braided.

(c) The flexible tube shall form part of an assembly that includes factory-fitted connections at each end, together with means for fixing the assembly to the ceiling support.

(d) The physical length shall be not greater than 3.7 m.

(e) The equivalent length of the assembly used for hydraulic calculations shall be in accordance with the manufacturer’s listing and be inclusive of two 90° bends.

(f) The complete assembly shall be listed by a recognised testing laboratory.

7.6 ORIFICE PLATES

Orifice plates fitted to assist in hydraulically balancing a High Hazard class system or to meet pump characteristic curves shall have an orifice diameter of not less than 50% of the diameter of the pipe into which the plate is to be fitted and shall comply with the requirements of Appendix C. Such orifice plates shall be permitted only in pipes of DN 50 or larger.

7.7 SUPPORT OF SPRINKLER PIPING

7.7.1 General

When a pipe support system is being designed for a fire sprinkler system, consideration shall be given to the correct location of pipe supports and to—

(a) the stresses and loads that may be imposed on the support system from all external causes, including differential movement of the building structure, and all internal causes, including pressure reactions;

(b) the transmission of vibration from the building to the piping and from the piping to the building; and

(c) the effect a corrosive atmosphere may have on the materials used.

Fire sprinkler piping support systems shall comply with the requirements of Clauses 7.7.2 to 7.7.7.6.

7.7.2 Design

Pipe supports shall:

(a) be designed to support twice the load due to water-filled piping plus a load of 115 kg at each point of support;

(b) confirm with the requirements of Clause 7.7.4;

(c) be capable of supporting the appropriate test load shown in Table 7.7.8.2.

7.7.3 Corrosion protection of pipe supports

Sprinkler piping supports installed in an aggressive environment shall be suitably protected against corrosion. NOTE: In bleach, dye and textile print works, paper mills, tanneries and in other premises where there are corrosive conditions, pipe supports should be thoroughly cleaned and protected by suitable means, e.g., two coats of good quality, bituminous paint, one coat being applied before and one after installation. Although this treatment will materially lengthen the effective life of the pipe supports, it will probably be found necessary to renew the coatings from time to time at intervals from one

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year to five years according to the severity of the conditions. As an alternative to the above treatment, galvanized pipe supports may be used.

7.7.4 Requirements for pipe support components (see Figures 7.7.8.1(A) and (B))

7.7.4.1 Hook bolts

The following requirements apply to the use of hook bolts:

(a) Hook bolts shall be used for clamping down purposes only.

(b) Hook bolts shall not be threaded along their full length.

(c) Hook bolts shall not be used for piping exceeding DN 80.

(d) Hook bolts shall conform to the dimensions given in Table 7.7.4.1.

TABLE 7.7.4.1

HOOK BOLTS

Pipe size Minimum nominal diameter of material, mm

≤DN 50 8

>DN 50 ≤DN 80 10

NOTE: The arms of hook bolts should be located on alternate sides along a length of pipe.

7.7.4.2 U-bolts clamping down

U-bolts clamping down shall comply with the dimensions given in Table 7.7.4.2:

TABLE 7.7.4.2

U-BOLTS CLAMPING DOWN

Pipe size Minimum nominal diameter of material, mm

≤DN 50 8

>DN 50 ≤DN 150 10

>DN 150 ≤DN 250 12

>DN 250 ≤DN 350 15

7.7.4.3 U-bolts clamping up and rods

U-bolts clamping up and rods shall comply with the dimensions given in Table 7.7.4.3:

TABLE 7.7.4.3

U-BOLTS CLAMPING UP AND RODS

Pipe size Minimum nominal diameter of material, mm

≤DN 50 6

>DN 50 ≤DN 150 12

>DN 150 ≤DN 250 15

>DN 250 ≤DN 350 20

7.7.4.4 U-hangers (clips)

U-hangers (clips) shall comply with the dimensions given in Table 7.7.4.4:

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TABLE 7.7.4.4

U-HANGERS (CLIPS)

Nominal pipe size Minimum nominal size of material, mm

≤ DN 40 1.6 × 25

> DN 40 ≤DN 65 3 × 25

> DN 65 ≤DN 150 6 × 30

7.7.4.5 Cantilever type supports, saddle brackets, girder or beam clamps

Cantilever type supports, saddle brackets, girder or beam clamps shall be designed in accordance with Clause 7.7.2.

7.7.4.6 Pipe bands

Pipe bands shall be fabricated from material complying with the following requirements:

(a) For non-corrosive atmospheres, in accordance with Table 7.7.4.6.

(b) For corrosive atmospheres, not less than 3 mm thick.

TABLE 7.7.4.6

PIPE BANDS

Pipe size Minimum material thickness, mm

≤ DN 100 1

> DN 100 3

7.7.4.7 Pipe support beams (trapeze bar)

Pipe support beams shall—

(a) be fabricated from material with section modulus equal to or greater than those calculated from the sections detailed below; or

(b) use mild steel angle conforming to the dimensions contained in Table 7.7.4.7.

TABLE 7.7.4.7

PIPE SUPPORT BEAMS

Nominal size of material, mm Pipe size

Max. span 2 m Max. span 3 m

≤ DN 40 40 × 40 × 6 65 × 40 × 6

> DN 40 ≤ DN 65 65 × 40 × 6 75 × 50 × 6

> DN 65 ≤ DN 150 100 × 65 × 8 100 × 75 × 8

NOTE: Where unequal angle is used, the longer arms should be vertical.

7.7.5 Fixing of pipe supports

7.7.5.1 General

Sprinkler piping may be supported from the building structure, provided the structure is capable of supporting the load. Where sprinklers are located below ducts, the piping may be supported from the duct supports, provided these have sufficient strength to support the combined design load.

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Sprinkler piping shall be supported independently of ceiling sheathing and any associated suspension system.

7.7.5.2 Fixing to concrete, brick or masonry

Wooden plugs or plugs of plastic material shall not be used for fixing pipe supports to concrete, brick or masonry. Explosive-powered fasteners (see AS 1873) through-bolts, expanding metal fasteners, or bolts or screws set in concrete may be used in this type of construction for fixing pipe supports. The fixing shall be capable of supporting the design load as required in Clause 7.7.2.

7.7.5.3 Fixing to timber

Acceptable methods of fixing to timber are wood screws, drive screws, coach screws and coach bolts. Nails shall not be used for fixing pipe supports to timber.

The following requirements shall apply:

(a) Wood screws shall not be hammer driven.

(b) Drive screws shall not be used for securing upwards.

(c) Wood screws or drive screws shall not be used for fixing piping exceeding DN 50.

(d) The fixing shall be capable of supporting the design load specified in Clause 7.7.2.

(e) Coach bolts and coach screws shall conform to the minimum dimensions given in Table 7.7.5.3.

TABLE 7.7.5.3

FIXING TO TIMBER

Pipe size Nominal diameter of coach bolt or coach

screw (mm)

Nominal length of coach screw (mm)

≤ DN 50 6 50

> DN 50 ≤ DN 150 12 75

> DN 150 ≤ DN 200 15 75

7.7.5.4 Fixing to steel

Explosive-powered fasteners may be used for fixing pipe supports to steel, provided the steel is not less than 5 mm thick. The fixing shall be capable of supporting the design load specified in Clause 7.7.2.

7.7.6 Spacing of supports

The distance between supports for horizontal and vertical sprinkler piping shall be in accordance with Table 7.7.6.

In certain types of construction, in which the minimum spacing required cannot be achieved by supporting pipes from main structural members, provision shall be made to support the centre of the span. A typical method is shown in Figure 7.7.6.

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FIGURE 7.7.6 TYPICAL METHOD OF SUPPORT FOR LONG SPAN

TABLE 7.7.6

MAXIMUM SPACING OF PIPE SUPPORTS

Maximum spacing of brackets and clips (m)

Plastic pipe Pipe size Copper and light wall steel pipe

Steel and ductile iron pipe Horizontal Vertical

DN 20 1.50 4.00 0.70 1.40

DN 22 — — 0.70 1.40

DN 25 2.00 4.00 0.75 1.50

DN 32 2.50 5.00 0.85 1.70

DN 40 2.50 5.00 0.90 1.80

DN 50 3.00 5.00 1.05 2.10

DN 63 — — 1.10 2.20

DN 65 3.00 5.00 1.20 2.40

DN 75 — — 1.30 2.60

DN 80 4.00 5.00 1.35 2.70

DN 90 4.00 5.00 1.40 2.80

DN 100 4.00 5.00 1.50 3.00

DN 110 — — 1.50 3.00

DN 125 4.00 6.00 1.70 3.40

DN 140 — — 1.70 3.40

≥ DN 150 4.00 6.00 2.00 4.00

7.7.7 Location of supports

7.7.7.1 General

Pipe supports shall be located such that they do not obstruct the distribution of water from any sprinkler.

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7.7.7.2 Change of direction

A support shall be located not further than 1 m from any change of direction in the piping, e.g., bend or elbow.

7.7.7.3 Range pipes

Range pipes exceeding 500 mm in length shall have at least one support. The first support on any range pipe shall be not more than 2 m from the distribution pipe or riser (drop). The distance from the last support to the end of a range pipe shall not exceed the following:

(a) For pipes ≤DN 25 ............................................................................................ 1.0 m.

(b) For pipes >DN 25 ............................................................................................ 1.5 m.

7.7.7.4 Distribution pipes

The first support on any distribution pipe shall be not more than 2 m from the connection to the main distribution pipe. The distance from the last support to the end of any distribution pipe shall not exceed 1 m.

7.7.7.5 Main distribution pipes

The distance from the last support to the end of any horizontal main distribution pipe shall not exceed 1 m.

7.7.7.6 Risers

Main vertical pipes rising (or dropping) from the installation valves, or for linking the piping between levels, shall be supported directly from the structure or by supports on horizontal branch piping from the riser not more than 300 mm from the riser.

7.7.8 Verification of design

7.7.8.1 General

Supports that comply with Clause 7.7.2 shall be deemed to meet the requirements for sprinkler piping support systems, see Figures 7.7.8.1(A), 7.7.8.1(B) and 7.7.8.1(C). NOTE: Where the support system is designed in accordance with Clause 7.7.2, details of the proposed pipe supports may be required by the regulatory authority. Where details submitted are considered to be inadequate, the regulatory authority may require a verification test, as specified in Clause 7.7.8.2.

7.7.8.2 Verification test

Where a verification test is required, pipe supports shall be capable of withstanding the following test without failure.

The appropriate load from Table 7.7.8.2 shall be applied without shock for a period not less than 30 s. NOTE: This test is not intended for application in situ. If applied in situ, appropriate safety precautions should be taken.

TABLE 7.7.8.2

VERIFICATION TEST LOADS

Pipe size Test load (nominal), kg

≤ DN 50 340

> DN 50 ≤ DN 65 385

> DN 65 ≤ DN 80 475

> DN 80 ≤ DN 100 680

> DN 100 ≤ DN 150 1200

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> DN 150 1750

FIGURE 7.7.8.1 (A) TYPICAL PIPE SUPPORT COMPONENTS

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FIGURE 7.7.8.1 (B) TYPICAL PIPE SUPPORT COMPONENTS

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FIGURE 7.7.8.1 (C) TYPICAL PIPE SUPPORT COMPONENTS

7.8 INSTALLATION—GENERAL

7.8.1 Pipe and pipe fitting specifications

7.8.1.1 General

All pipes and pipe fittings in an installation shall be new and shall comply with the relevant Standards listed in Clause 1.5.

7.8.1.2 Pipes above ground

Pipes above ground shall comply with the following:

(a) Clause 7.9 of this Standard for steel.

(b) Clause 7.10 of this Standard for light wall steel.

(c) Clause 7.11 of this Standard for copper.

(d) Clause 7.12of this Standard for plastic.

7.8.1.3 Pipes below ground

Pipes below ground shall comply with the relevant Standards listed in Clause 1.5, subject to the approval of the water supply authority, and the following:

(a) Clause 7.9 of this Standard for steel.

(b) Clause 7.10 of this Standard for light wall steel.

(c) Clause 7.11 of this Standard for copper.

(d) Clause 7.12 of this Standard for plastic.

7.8.1.4 Protection of underground pipes

Underground pipes shall be protected against corrosion, where necessary, and shall not be laid in positions where they could be damaged by vehicular traffic.

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7.8.2 Welding of piping

Welding of piping shall comply with the provisions set out in AS 4041.

7.8.3 Hydrostatic pressure test

All new installations, trunk mains and water supply connections shall be capable of withstanding, for a period of 2 h without loss of pressure, a hydrostatic test pressure of 1.4 MPa, or 400 kPa in excess of the maximum static working pressure, whichever is the greater.

7.8.4 Pneumatic leak test

In areas where water-sensitive equipment or goods may be installed or stored it is recommended that prior to carrying out the hydrostatic pressure test (see Clause 7.9.3) the integrity of pipe jointing be established by conducting a pneumatic leak test of the pipework in these areas.

The system jointing shall be capable of holding a maximum of 300 kPa pneumatic pressure for period of 30 min without more than 10% loss of the starting pressure, with a 10 min temperature normalizing period prior to the starting pressure reading.

C7.8.4 It is considered unsafe to conduct pneumatic pressure testing on pipework systems using malleable fittings and threaded joints due to danger of the uncontrolled sudden release of compressed gases as well as the potential of catastrophic failure and fragmentation of a pipe fitting.

7.8.5 Embedding of piping

Sprinkler piping shall not be embedded in concrete floors or any other surfacing material of a building. NOTE: Embedding of piping is prohibited for two principal reasons—

(a) problems of corrosion; and (b) difficulties in making subsequent alterations to the pipe system.

7.8.6 Corrosion protection of piping

Black steel sprinkler piping shall be painted with at least one coat of etch prime. Piping installed in an aggressive environment shall be further protected against corrosion.

7.8.7 Protection of piping against mechanical damage

Sprinkler piping shall be protected against mechanical damage. NOTE: Sprinkler piping should not be erected in locations where it is liable to damage by forklift trucks and other mobile equipment; in particular, it should not cross gangways where such equipment is used unless the headroom is in excess of the height of the equipment concerned. Where it is impracticable to avoid areas subject to such traffic, the piping should be protected by adequate guards. Where installation valves or risers are situated in such areas, in addition to guardrails, safety guidelines should be marked out.

7.8.8 Facilities for flushing piping

Where the water supplies include an automatic pump drawing from a source of non-potable water such as a canal, river or lake, flushing connections shall be provided at the extremities of distribution pipes.

7.8.9 Prohibited use of piping

7.8.9.1 Electrical earth

Sprinkler pipes shall not be used as a means of earthing an electrical installation or as a link in an earth circuit.

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7.8.9.2 Hoisting

Sprinkler pipes shall not be used for hoisting or supporting other services nor shall articles be hung from them.

7.8.10 Pipe sizes

Pipe size shall be determined by full hydraulic calculation, in accordance with the requirements for the class of hazard.

7.8.11 Spacing of brackets and clips

Brackets and clips shall be spaced in accordance with Table 7.7.6.

7.9 INSTALLATION—STEEL PIPING

7.9.1 Pipe and pipe fitting specifications

7.9.1.1 General

All pipes and pipe fittings in an installation shall be new and shall comply with the relevant Standards listed in Clause 7.1.

7.9.2 Pipes

7.9.2.1 Pipes above ground

Pipes above ground shall be at least equivalent to medium steel tube complying with the requirements of—

(a) AS 1074; or

(b) AS 1579; or.

(c) AS 4041.

7.9.2.2 Pipes below ground

Pipes below ground shall comply with the relevant Standards listed in Clause 1.5, subject to the approval of the water supply authority.

Cast iron pipes and fittings complying with AS 1724 and AS 2544 shall be coated and cement mortar lined in accordance with AS 1281 or AS 1516.

Pipes complying with AS 1074 and AS 1579 shall be subject to a minimum wall thickness of 5.3 mm.

7.9.3 Pipe jointing

7.9.3.1 Welded joints

Only pipes of DN 50 or greater may be jointed by welding unless the joints are fabricated, welded and inspected in the workshop.

On-site welding operations shall be avoided as far as possible, but if unavoidable they shall be carried out in accordance with AS 1674. NOTE: Where galvanized pipe on the supply side of the main control assembly is welded, the water supply authority may require the galvanized finish to be made good.

7.9.3.2 Rolled groove fittings

Pipes may be joined by roll grooved fittings. NOTE: A rolled groove fitting is a formed ductile iron cast fitting designed to ensure watertightness by means of a synthetic rubber gasket. The fitting housing is in two sections and fully encloses the gasket when assembled. The housing engages around the full circumference of the roll grooved pipe end and is assembled using nuts and bolts ensuring engagement of the pipe and fitting.

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7.10 INSTALLATION—LIGHT WALL STEEL PIPING

7.10.1 Pipe and pipe fitting specifications

All pipes and pipe fittings in an installation shall be new and shall comply with the relevant Standards listed in Clause 1.5 and with the requirements and limitations stipulated in the listing criteria.

7.10.2 Pipes

7.10.2.1 Above ground

Pipes with a nominal wall thickness of less than 2.0 mm may only be installed above ground and downstream of any main control or isolating valve.

Where light wall pipes installed above ground are required by other Standards or water authorities, or are in corrosive environments, they shall be galvanized and the galvanizing shall comply with the requirements of AS 1650.

7.10.2.2 Below ground

All light wall pipe installed below ground shall be hot-dip galvanized in accordance with the requirements of AS 4118.2.1.

All fittings for installation below ground shall be hot-dip galvanized in accordance with the requirements of AS 1650.

Where pipes and pipe fittings are installed below ground and additional protection is required, it shall be provided in accordance with the requirements of AS 4118.2.1.

7.10.3 Pipe jointing

7.10.3.1 Welded joints

The fabrication of light wall steel pipes shall be limited by the requirements of Section 3 of AS 4118.2.1.

7.10.3.2 Fittings and other pipe jointing methods

Only fittings and mechanical pipe jointing methods complying with the requirements of AS 4118.2.1 shall be used.

7.10.3.3 Fittings

Fittings shall be dimensionally compatible with the pipe and shall only be used with a pipe for which they were specifically designed, approved and listed.

7.11 INSTALLATION—COPPER PIPING

7.11.1 General

All pipes and pipe fittings in an installation shall be new and shall comply with the relevant Standards listed in Clause 1.5.

Copper piping shall be installed in accordance with the requirements of relevant sections of AS/NZS 3500.1 and shall only be used in wet fire sprinkler systems (see Clause 1.4.30) for hazard classifications up to Ordinary Hazard 3 special.

7.11.2 Pipes

7.11.2.1 Pipes above ground

Copper piping above ground shall be at least equivalent to Type ‘B’ tube complying with the requirements of AS 1432.

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7.11.2.2 Pipes below ground

Copper pipes below ground shall be installed in accordance with the requirements of AS/NZS 3500.1 for the installation of water supplies.

7.11.3 Pipe jointing

7.11.3.1 Brazing

Joints in copper piping, or between copper piping and fittings, shall be silver brazed, except that solder may be used when the fitting is designed for that purpose. Silver brazing filler materials shall conform to Types B2, B3 or B4 of AS 1167. Solder shall be either tin-antimony or tin-silver to AS 1834.

On-site brazing or soft soldering shall be carried out in accordance with AS 1674. NOTE: Where dissimilar metals are joined, care should be taken to insulate copper piping to prevent bimetallic corrosion.

7.11.3.2 Soft-soldered joints

Where piping is concealed within ceiling or void spaces, the use of soft-soldered joints is permitted for Light Hazard and Ordinary Hazard 1 occupancies (see Appendix A).

7.11.3.3 Manipulated joints

The deformation of the piping to form the joint shall only be effected using the appropriate tools.

Joints formed in this manner shall only be silver-brazed. Means shall be provided to prevent the branch pipe from intruding into the bore of the main pipe while maintaining the joint close contact.

7.11.3.4 Capillary fittings

Capillary fittings including solder and brazing materials shall be manufactured and used in accordance with AS 3688.

7.11.3.5 Compression fittings

Compression fittings shall be manufactured using the dimensions and materials set out in AS 3688.

7.11.4 Pipe bending

Copper piping may be bent, provided there are no kinks, ripples, distortions, reduction in diameter or any noticeable deviation from round. The minimum radius of a bend shall be 6 pipe diameters for pipe sizes DN 50 and smaller and 5 pipe diameters for pipe sizes DN 65 and larger.

7.12 INSTALLATION—PLASTIC PIPING

7.12.1 Pipe and pipe fitting specifications

7.12.1.1 General

This Clause specifies requirements for the use of plastic piping for wet fire sprinkler systems. Use of plastic piping in fire sprinkler systems is limited to Light Hazard systems and the mechanical, service and related storage areas of these occupancies that are defined as Ordinary Hazard 1.

All pipes and pipe fittings in an installation shall be new and shall comply with the requirements of AS 4118.2.1 and the requirements and limitations of any listing criteria.

Only straight lengths of pipe are approved for installation according to this Standard. The use of coiled pipe is not approved.

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All fittings designed to take a male metal thread shall incorporate a female metal thread insert and a metal reinforcing ring to provide a high-strength, heavy duty fitting.

7.12.1.2 Pipe and pipe fittings above ground

Plastic pipes and pipe fittings will be fully enclosed by walls, ceiling or other closed architectural structures of the building to be protected.

The only permitted exposure to the room being protected is at the connection to the sprinkler and only if the configuration has been shown to satisfactorily pass the test in AS 4118.2.1.

Where plastic pipe is used in non-protected areas of buildings, no pipe or fitting shall project above ground or pass through any element of the building structure unless it is adequately protected from structural damage (see also Clauses 7.3, 7.8.7 and 7.12.1.4).

7.12.1.3 Pipes and pipe fittings below ground

Pipes and pipe fittings laid underground shall comply with the relevant Standards listed in Clause 1.5 subject to the approval of the water supply authority.

Approved plastic pipes and pipe fittings shall be laid in accordance with the requirements of AS/NZS 3500.1 for water supply installation.

7.12.1.4 Installation restrictions

Plastic pipes and pipe fittings shall not be installed within 300mm of heat-producing sources such as light fixtures, ballasts, heat ducts and steam pipes, unless the pipe is rated for such heat exposures.

Plastic pipes and pipe fittings shall not be installed in areas where the maximum ambient temperature exceeds 50°C.

Where thermal expansion or contraction forces are expected due to significant variations in temperature, these forces shall be allowed for by the installation of sufficient expansion joints, or by other suitable methods as recommended by the manufacturer. NOTE:Gypsum wallboard may be an acceptable concealment material.

7.12.1.5 Pipe storage

Unless specified by the manufacturers as being suitable for continuous outdoor exposure, plastic pipes shall be stored under cover.

7.12.2 Pipe and fittings—Jointing

7.12.2.1 Jointing

Pipework may be joined by ei ther; solvent cementing, screwed or mechanical joints, crimp type fittings or by heat fusion. If screwed joints are used then the presence of the screw thread must not reduce the effective wall thickness below that of the pipe.

7.12.2.2 Threaded connections

A thread sealant shall be used in making threaded connections. NOTE: Polytetrafluorethylene (PTFE) tape is the recommended sealant and should be used with all threaded connections. Some thread pastes contain solvents and may be damaging to plastic pipes. They are therefore not recommended for use with plastic pipes. Maximum tightening torque for threaded connections should not exceed 35 Nm.

7.12.3 Corrosion protection of piping

Metallic piping used in conjunction with plastic sprinkler pipework installed in an aggressive environment shall be protected against corrosion.

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S E C T I O N 8 V A L V E S A N D A N C I L L A R Y E Q U I P M E N T

8.1 CONTROL ASSEMBLIES

8.1.1 General

Each installation shall be provided with a control assembly which is located in a sprinkler valve enclosure in accordance with BCA Specification E1.5, and comprising the following:

(a) A main stop valve (see Clause 8.2.2).

(b) A valve, comprising either—

(i) an alarm valve (wet) (see Clause 8.10.1) or an alarm valve (dry) (see Clause 8.10.2); or

(ii) a composite alarm valve suitable for either wet or dry systems (see Clause 8.10.3).

(c) A water motor alarm, with lock-open alarm cock (see Clauses 8.13.3, 8.13.7, 8.13.8 and 3.4).

(d) Where facilities are available, alarm signalling equipment (ASE) with locked-open alarm cock (see Clause 3.3).

(e) A main drain valve and a test valve (see Clauses 7.5.1 and 8.13.8).

(f) Where required, an alarm retarding device or a means to maintain installation pressure (see Clause 8.13.2).

(g) Installation and water supply pressure gauges (see Clause 8.15).

(h) A plan of the protected building(s) and property, that is, a block plan (see Clause 8.3).

(i) A pressure gauge schedule (see Clause 8.6).

(j) Emergency instructions (see Clause 8.5).

(k) A ‘sprinkler stop valve inside’ plate (see Clause 8.4).

(l) A notice identifying the installation and the area served by the installation.

8.1.2 Designated site and building entry points

Where multiple buildings exist on a site, a designated building entry point (DBEP) shall be identified for each sprinkler-protected building. It shall be indicated by a strobe, activated by alarm valve operation and located on the outside of the building, visible at the designated site entry point (DSEP). The power supply to the strobe shall be taken from the building’s fire indicator panel.

NOTES: 1 In the absence of a fire indicator panel, the power supply may be taken from the alarm

signalling equipment/brigade transmitter. 2 At least one designated site entry point (DSEP) should be nominated where multiple buildings

are monitored on a site, unless each building is individually identified at the fire dispatch centre.

8.2 STOP VALVES

8.2.1 General

All stop valves shall be of the self-indicating type (except those fitted by the water supply authorities on the branches from a town main) shall comply with the requirements of AS 4118.1.6.

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All valves on the water supply side of the sprinkler alarm valves shall be subject to the requirements of the water supply authority.

8.2.2 Main stop valves

Water supplies to each sprinkler installation shall pass through a main stop valve. Before passing through the main stop valves, water supplies shall be combined. The main stop valve shall be secured open by a padlocked or riveted strap and shall be adequately protected from the effect of frost. NOTE: Provision should be made for closure of the main stop valve to give a visible and audible alarm at a place under constant surveillance

8.2.3 Stop valves controlling water supplies

All stop valves controlling water supplies shall have a unique identification and be clearly shown on the block plan (see Clause 8.3(b)) and be secured open by a padlocked chain (except those under control of the water supply authority). In the case of elevated private reservoirs and gravity tanks, the stop valve shall be fixed close to the non-return valve and on the reservoir or tank side thereof.

8.2.4 Subsidiary stop valves

Stop valves controlling the flow of water to any sprinkler shall not be fitted downstream of the alarm valve except in the following circumstances—

(a) where monitored in accordance with Clause 3.3; or

(b) where hoods over drying ends of a papermaking machine apply, to enable cylinders to be changed; or

(c) where allowance is made for the removal of not more than two sprinklers to facilitate the use of an access hatch; or

(d) where controlling groups of external sprinklers. NOTE: The valve is not required to be monitored

8.3 BLOCK PLAN

A plan of the protected building(s) (block plan) (see Figure 8.3) with the position of the main stop valves clearly indicated shall be placed adjacent to each set or group of installation control assemblies where it can be readily seen. The block plan shall be in the form of a permanent diagram, that is water-resistant and fade-resistant, and shall include—

(a) the layout of the protected buildings or areas and adjacent streets;

(b) a diagram of water supplies including—

(i) sizes, dimensioned locations and unique identification of water supply valves;

(ii) supply authority mains; and

(iii) connections for non-industrial purposes and capacity and locations of storage tanks;

(c) the location of control assemblies, subsidiary stop valves, remote test valves, tail-end air valves, anti-freeze devices, drains, air release valves, orifice plates, external sprinklers and any unusual features of the system;

(d) the name of the installer;

(e) the location of all pumps;

(f) the year of installation of the system and of any major extension thereto;

(g) identification of the area(s) related hazard classification(s), design density(ies) if applicable, and required flow(s) and pressure(s); and

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(h) identification of the floor area protected by each sprinkler installation control assembly.

FIGURE 8.3 TYPICAL BLOCK PLAN

8.4 ‘SPRINKLER STOP VALVE INSIDE’ PLATE A plate shall be fixed on the outside of an external wall, as near to the main stop valve as possible, bearing the following words in clear permanent lettering:

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SPRINKLER STOP VALVE

INSIDE

NOTE: The words ‘SPRINKLER STOP VALVE’ should be in letters at least 35 mm high, the word INSIDE in letters at least 25 mm high and the letters set in white on a black background.

8.5 EMERGENCY INSTRUCTIONS

The following instructions together with an appropriate valve diagram shall be permanently displayed at the control assembly:

EMERGENCY INSTRUCTIONS

1 CALL FIRE BRIGADE [000]……

2 MAKE SURE FIRE IS OUT.

3 CLOSE MAIN STOP VALVE (SHUTTING OFF WATER SUPPLY).

4 OPEN MAIN DRAIN VALVE (DRAINING INSTALLATION).

5 CALL MAINTENANCE CONTRACTOR . . . .

6 REMAIN AT VALVES.

IF FIRE RE-OCCURS—

(A) CLOSE MAIN DRAIN VALVE, AND

(B) RE-OPEN MAIN STOP VALVE.

NOTE: The name and contact number of the maintenance contractor should be inserted.

8.6 PRESSURE GAUGE SCHEDULE

A pressure gauge schedule, expressed in kilopascals, see Figure 8.6, shall be located adjacent to each group of installation control assemblies. It shall be in the form of a permanent chart that is water-resistant and fade-resistant, and shall include the following:

(a) Minimum and maximum standing installation pressure for each installation.

(b) Minimum and maximum standing below-stop-valve pressure(s) (combined main).

(c) Minimum and maximum standing primary water supply pressure.

(d) If applicable, minimum and maximum standing secondary water supply pressure;

(e) If applicable pressure tank—

(i) minimum and maximum air pressure;

(ii) air compressor cut-in and cut-out pressures; and

(iii) low air pressure alarm setting.

(f) Pump cut-in pressure(s).

(g) Pump shut-off pressure(s).

(h) If applicable, pump pressure-reducing valve operating pressure.

(i) If applicable, trunk main pressure maintenance (jockey) pump cut-in and cut-out pressures.

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(j) If applicable, installation pressure maintenance (jacking) pump cut-in and cut-out pressures.

(k) If applicable, installation air pressure (dry systems).

(l) If applicable, installation pressure reducing valve —

(i) upstream pressure;

(ii) downstream (reduced) pressure; and

(iii) relief valve operating pressure.

Pressure kPa

Items Normal Minimum Maximum

Installation 1 850 750 850

Installation 2 850 750 850

Below stop valve (combined main) 850 750 850

Town main 1 (primary water supply) 500 300 600

Town main 2 (secondary water supply) 500 300 600

Electric pump delivery pressure at shut-off (churn without water flow)

900 700 1000

Diesel pump delivery pressure at shut-off (churn without water flow)

600 600 600

System pressure reducing valve (upstream) 700 600 1000

System pressure reducing valve (downstream) 700 600 800

Pumps Cut-in pressure kPa

Cut-out pressure kPa

Pressure maintenance (jockey) pump 600 700

Installation pressure maintenance (jacking) pump 700 800

Electric pump 550 —

Diesel pump 500 —

Pressure relief valves Opening kPa Closing kPa

System pressure reducing valve—relief valve setting 750 700

Pump pressure relief valve 1000 950

FIGURE 8.6 TYPICAL PRESSURE GAUGE SCHEDULE

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8.7 SYSTEM INTERFACE DIAGRAM

A system interface diagram illustrating interconnections between the sprinkler system and other fire safety features shall be located adjacent to the installation control assembly(ies). A system interface diagram is shown in Figure 8.7.

Function

System

Stai

r pr

essu

riza

tion

Doo

r re

leas

es

Roo

f ven

ts

Soun

d sy

stem

s [1

]

Plan

t shu

tdow

n

Fuel

isol

atio

n

Ele

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r ov

erri

de

Ala

rm m

onit

orin

g

Smok

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haus

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s

Smok

e cu

rtai

ns

Smok

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ill m

ode

HV

AC

shu

tdow

n

Fire

pum

p

Dam

per

clos

ure

Sprinkler systems ● ● ● ● ● ●

Detection systems ● ● ● ● ● ● ● ● ● ● ● ● ●

Smoke/heat alarm systems ● ● ● ● ● ● ● ● ●

Gaseous systems ● ● ● ● ● ●

Aerosol systems ● ● ● ● ● ●

Water mist systems ● ● ● ● ● ●

Hydrants ● ● ●

Hose reels ● ● ●

Kitchen suppression systems [2] ● ● ● ● ● ● ● ●

[1] For emergency purposes [2] Pre-engineered

FIGURE 8.7 SYSTEM INTERFACE—INDICATIVE ONLY

8.8 STOP, DRAIN AND TEST VALVES, AND ALARM COCKS

All stop, drain and test valves, and alarm cocks shall be permanently identified to show their function and normal operating position.

8.9 NON-RETURN (BACK-PRESSURE) VALVES

Where there is more than one water supply to an installation, a non-return valve shall be fitted in each water supply pipe and a test cock shall be provided between the non-return valve and the supply control valve in accordance with the requirements of the water supply authority. Non-return valves shall be readily accessible for testing and maintenance.

All valves on the water supply side of the sprinkler alarm valves shall be subject to the requirements of the water supply authority.

Where the fitting of a non-return valve below ground is unavoidable, the position of the valve shall be indicated and an inspection chamber shall be provided.

Where an elevated private reservoir or gravity tank forms one of the supplies, the non-return valve on the supply pipe shall be not less than 5 m below the base of the reservoir or tank.

All non-return valves shall comply with the requirements of AS 4118.1.6.

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8.10 ALARM VALVES

8.10.1 Wet

Alarm valves (wet) shall comply with the requirements of AS 4118.1.2. They shall be fixed on the main supply pipe immediately above the main stop valve and before any connection is taken off to supply any part of the installation.

8.10.2 Dry

Alarm valves (dry) shall comply with the requirements of AS 4118.1.7. They shall be fixed on the main supply pipe immediately above the main stop valve and the alarm valve (wet) in installations on the alternate wet and dry system not employing a composite alarm valve as specified in Clause 8.10.3 and before any connection is taken off to supply any part of the installation.

In dry systems maintained permanently under air pressure, the water motor alarm shall be connected to the atmospheric chamber or the alarm motor auxiliary valve of the alarm valves (dry). NOTE: In order to facilitate the carrying out of flow tests when an installation is under air pressure, an additional drain valve, of a size appropriate to the hazard class, may be fitted. Alternatively, a stop valve may be installed immediately above the alarm valve (dry) (see Clause 8.2.4(a)).

8.10.3 Composite alarm valves

Composite alarm valves shall comply with the requirements of AS 4118.1.7 and shall be fitted on the main supply pipe and immediately above the main stop valve before any connection is taken off to supply any part of the installation. NOTE: Composite alarm valves are dual purpose, that is, they may be used in either wet or dry systems.

8.10.4 Accelerators or exhausters for alarm valves (dry system)

Accelerators are devices that are designed to accelerate the operation of an alarm valve (dry) (see Clause 2.1.2.4). They shall be located as close as possible to the alarm valve (dry) or composite alarm valve. The connection to the device from the system shall be so located that the restriction orifice and other opening parts are not likely to become flooded with priming water or back drainage under normal conditions.

8.10.5 Identification of control assemblies and water motor alarms

In buildings containing more than one installation, each control assembly and alarm signalling equipment (ASE) (see Clause 3.2) shall have number(s) indicated thereon and the relevant water motor alarm (see Clause 3.3) shall bear the same number(s) in bold figures.

8.11 PRESSURE-REDUCING VALVE STATIONS

Installation pressure-reducing valves shall comply with the requirements of AS 4118.1.8. Operating details shall be included on the pressure gauge schedule (see Clause 8.6) and at the pressure-reducing valve station.

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8.12 DELUGE AND PRE-ACTION VALVES

8.12.1 Deluge valves

Deluge valves shall comply with the requirements of AS 4118.1.5. NOTE: Deluge valves are used to control the water to an array of open sprinklers or sprayers (see Clause 2.3.2.7), which are required to discharge simultaneously. The valve, normally held closed, is released automatically either by the loss of air pressure from independent piping carrying sprinklers acting as heat detectors, or by the operation of heat or smoke detection system. Alarm equipment is normally connected to the outlet piping from the valve so that an alarm is given when water flows into the distribution piping.

8.12.2 Pre-action valves

Pre-action valves shall comply with the requirements of AS 4118.1.5. NOTE: These valves are used for either of the following purposes:

(a) To control the water supply to a dry sprinkler installation to prevent water discharge from piping or sprinklers which have suffered mechanical damage. The valve, normally held closed, is released by the operation of a heat or smoke detection system and is of similar type to the deluge valve described in Clause 8.12.1, but the sprinkler piping will be charged with air.

(b) To admit water to the piping of a dry installation prior to the operation of a sprinkler or sprinklers. The valve may be a standard alarm valve (dry) (which may be fitted with an accelerator). The heat or smoke detection system is arranged to trip the valve in a similar manner to the operation of an exhauster.

8.13 ALARM DEVICES

8.13.1 General

Each installation shall be so arranged that the installed alarm devices (see Clauses 3.2 and 3.3) shall respond within 3 min of opening the test valve with a 15 mm bore referred to in Clause 8.13.7 and within 6 min of opening the remote test valve referred to in Clause 8.14.

8.13.2 Prevention of false alarms

Where water supplies include a town main known to have widely fluctuating pressure characteristics such that the normal installation pressure is exceeded, causing intermittent operation of the alarm valve, false alarms shall be prevented by one of the following means:

(a) Installation of a listed retarding device.

(b) Maintenance of the installation pressure above the maximum anticipated mains pressure. This may be accomplished in one of three ways, as follows:

(i) Manually operated hand jacking pump.

(ii) Motorized jacking pump, manually controlled by spring-loaded (inching) pushbutton.

(iii) Motorized jacking pump, automatically started and stopped, fitted with a normally closed stop valve and an orifice not exceeding 3 mm diameter on the discharge side to restrict the flow. An unrestricted bypass may be fitted around the orifice to facilitate the initial elevation of the installation pressure to the required set level (see Figure 8.13.2). NOTE: The restricting orifice is required to ensure that the automatic jacking pump does not satisfy the flow demand of a single operating sprinkler, thus bypassing the alarm valve. It will also restrict any potential damage caused by an undetected leak in the installation.

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FIGURE 8.13.2 TYPICAL SCHEMATIC AUTOMATIC INSTALLATION PRESSURE MAINTENANCE (JACKING) PUMP

8.13.3 Water motor alarms

8.13.3.1 General

Local water motor alarms shall comply with the requirements of AS 4118.1.3. NOTE: Where an alarm bell is required to be installed in a high-level valve room, a pressure switch and electronic bell may be installed in lieu.

8.13.3.2 Height above valve

Water motor alarms shall be located not higher than 6 m above the control assembly (ies).

8.13.3.3 Piping finish and size

The piping shall comply with the requirements of AS 4118.2.1.

The size of pipe shall be as follows:

(a) Where the length of the piping to the alarm does not exceed 6 m, it shall be not less than DN 15.

(b) Where the length of the piping to the alarm exceeds 6 m but does not exceed 25 m, it shall be not less than DN 20.

(c) Where the length of the piping exceeds 25 m, it shall be not less than DN 25.

8.13.3.4 Drainage provisions

Dry, pre-action and all systems in which the water motor alarm piping could be subject to freezing shall have such piping arranged to drain through a fitting having an orifice not larger than 3 mm diameter. The orifice plate (which may be integral with the fitting) shall be either stainless steel or a suitable non-ferrous material such that the hole will not become blocked by products of corrosion.

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8.13.3.5 Alarm valve not to be bypassed

Except for an automatic pressure maintenance jacking pump complying with Clause 8.13.2, or a water supply shunt apparatus installed for the purpose of continuous main stop valve supervision, no connection between the water supply piping and water motor alarm shall directly bypass the alarm valve.

8.13.4 Fire alarm signal

Fire alarms (see Clause 3.2) connected either directly to a fire service or via a fire alarm monitoring service shall be initiated by—

(a) a flow of water from the alarm valve through a water motor device;

(b) a flow of water from the valve causing actuation of a pressure switch; or

(c) a fall in pressure in the system piping above the alarm valve.

Where a fire alarm pressure switch is located on the water motor alarm line, the lock-open valve controlling the water motor alarm shall be positioned on the water motor alarm side of the pressure switch connection. Where an installation is on the dry system, means shall be employed to ensure that pressure operation of the switch cannot be prevented either in the event of a fire or during testing of the water motor alarm. NOTE: Auxiliary alarms may take the form of electric flow or pressure switches. They should be incorporated in the system piping above the alarm valve to indicate at a central location.

8.13.5 System interface alarm signal

System interface alarm signals (see Clause 3.2) to other building fire safety systems, such as the building occupant warning system, requiring a fire mode response to a sprinkler system operation shall be initiated by—

(a) a flow of water from the alarm valve through a water motor device;

(b) a flow of water from the valve causing actuation of a pressure switch;

(c) a fall in pressure in the system piping above the alarm valve; or

(d) a flow of water through a flow switch.

8.13.6 Lock-open valve

The pipe feeding hydraulically operated alarms shall be fitted with a lock-open valve.

8.13.7 Testing of alarm devices

Alarm devices shall be tested through a 15 mm test valve located downstream of the alarm device simulating the operation of a sprinkler. Installations on the alternate wet and dry system using both wet and dry alarm valves shall have testing valves fixed both above the dry alarm valve (for use when the installation is under water pressure) and between the wet and dry alarm valves (for use when the installation is under air pressure). NOTE: The test procedures are set out in AS 1851.

8.14 REMOTE TEST VALVES

For the purpose of commissioning and periodic testing, a remote test valve shall be provided on each installation (see Figure 8.14).

The remote test valve piping shall not be less than DN 25 and shall be taken from the end of a range pipe in the most remote group of sprinklers on the installation.

Where the most remote group of sprinklers is not the highest in the installation, an additional remote test valve shall be connected to the range pipe at the highest level.

The test pipe shall terminate in a smooth bore, corrosion-resistant orifice giving a flow equivalent to the smallest orifice sprinkler representative of the installation.

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The remote test valve shall be readily accessible, locked shut, and shall be labelled as follows:

SPRINKLER REMOTE TEST VALVE—TO BE LOCKED SHUT

FIGURE 8.14 TYPICAL REMOTE TEST VALVE

8.15 PRESSURE GAUGES

Pressure gauges shall comply with the requirements of AS 1349 and shall have scales with graduations in accordance with Table 8.15.

Means shall be provided to enable each pressure gauge to be readily removed without interruption to installation water supplies.

Gauges to monitor pressures shall be installed in the system at the following locations:

(a) Immediately above the alarm valve.

(b) Adjacent to the main stop valve, connected to indicate the pressure of each water supply. The connection for such gauges shall be on the supply side of the non-return valve nearest the supply.

NOTE: For multiple installation systems, each subsequent main stop valve, or group of main stop valves, may be fitted with a gauge indicating trunk main pressure only.

(c) On the delivery side of all pumps.

(d) On the suction side of all pumps.

(e) On all pressure tanks (see Clause 8.6(e)).

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TABLE 8.15

GRADUATION OF PRESSURE GAUGES

Maximum scale reading

Maximum graduation interval

MPa kPa

1.0 1.6

>1.6

20 50

100

NOTE: The maximum scale value of gauges should be approximately 150% of the known maximum pressure.

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S E C T I O N 9 L I G H T H A Z A R D C L A S S S Y S T E M S

9.1 GENERAL

This Section specifies the requirements for the design of standard sprinkler system protection for a Light Hazard class sprinkler system .

9.2 DESIGN DATA

Light Hazard systems shall be fully hydraulically designed to provide a flow of at least 48 L/min from each sprinkler within the design area (see Clause 1.3.8). The design area shall consist of each group of six sprinklers in all parts of the building regardless of the area covered by individual sprinklers.

Each array of sprinklers shall be selected to form, as near as possible, a square with the longer side positioned such that it imposes the greatest hydraulic demand. Except as varied by this Clause, hydraulic calculation methods shall conform to the requirements of Section 12.

9.3 WATER SUPPLY

9.3.1 Flow and pressure requirements

The water supply shall be capable of providing the minimum flow and pressure requirements of the system as determined by the hydraulic calculation methods described in Clause 9.2.

Where pumps are provided, they shall be capable of operating at the maximum flow rate of the system (Qmax.) see Clause 12.9.2. NOTE: Where the flow requirements in a multistorey building at point of inter section (Qmax.) exceed 150% of the hydraulically most favourable system flow, consideration should be given to using pump suction tanks in lieu of town mains supply (see Clause 4.2.2.4).

9.3.2 Water storage capacity

The effective water storage capacity of a reservoir or pump suction tank dedicated as a sprinkler system supply shall comply with BCA Specification E1.5.

The storage capacity of a reservoir or pump suction tank that is the sole water source of a single water supply system may be reduced by up to two thirds, for buildings up to 25 m in effective height; subject to the provision of an automatic inflow to the reservoir or pump suction tank which is sufficient for the pump to operate at the maximum flow rate (see Clause 12.9.2) for not less than 60 min.

The source and reliability of the automatic inflow shall conform to the requirements of Clause 4.1 and Clause 4.3.2.

The storage capacity of a reservoir or pump suction tank, which is part of a dual water supply system, may be reduced by one third without the provision of the automatic inflow to compensate for the reduced tank capacity.

C9.3.2 A dual water supply consisting of reservoirs or pump suction tanks provides an increased level of reliability and continuity of supply compared to a single supply. The total capacity of the dual supply provides, in normal operation, 4/3 of the required storage capacity albeit there will be a 1/3 deficit in the required storage capacity for the duration of any period during which one reservoir or tank may be out of service.

For purposes of tank refilling, the requirements of Clause 4.3.4 shall apply.

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9.3.3 Additional storage capacity

The water requirement of any hydrant or other fire protection system connected to the sprinkler system water supply shall be added to the water storage capacity.

9.3.4 Pump suction tanks

Pump suction tanks shall be constructed in accordance with the requirements of Clause 4.3.4.

9.3.5 Pressure tanks

Notwithstanding the requirements of Clause 9.3.3, the minimum quantity of water to be maintained in a pressure tank reserved entirely for sprinklers shall be a minimum of the calculated flow rate for the most unfavourable array of sprinklers for the required duration

In all other respects, pressure tanks shall conform to the requirements of Clause 4.3.7.

9.3.6 Pumpsets

Pumpsets shall comply with the requirements of Clauses 4.3.8 and 4.3.9.

The duty flow and pressure of the pump(s) shall be not less than the flow and pressure calculated in accordance with Clause 9.3.1.

The minimum combined output of the pump and its supply shall satisfy the requirements of all portions of the system as required by Clause 4.3.8.4 and Figure 4.3.8.4(A) and (B).

9.3.7 Proving of water supplies

Water supplies shall be proved to meet the calculated requirements of the installed system.

Proving of water supplies shall be in accordance with the requirements of Clause 4.4.

9.4 SPRINKLERS

9.4.1 Size and type

Sprinklers shall be in accordance with AS 4118.1.1, and—

(a) have a nominal orifice size of 10 mm;

(b) be fast response sprinklers; and

(c) be either pendent, upright, sidewall, flush, recessed or concealed spray sprinklers.

9.4.2 Maximum area coverage per sprinkler

Except for the reduced coverage required by Clause 9.4.3, the maximum area covered by sprinklers shall be as follows:

(a) Sidewall sprinklers ............................................................17 m2 (see also Section 5).

(b) Other sprinklers .................................................................21 m2 (see also Section 5).

The area covered by each sprinkler shall be defined by lines drawn midway between adjacent sprinklers at right angles to the line joining the sprinklers and by the boundary of the area covered (see Figure 12.2).

9.4.3 Reduced coverage

In attics, basements, boiler rooms, kitchens, laundries, storage areas, workrooms, electronic data processing rooms, airconditioning and building services plant rooms, restaurants and cafes, the maximum area coverage shall be 12 m2

per sprinkler. The maximum distance between sprinklers shall be 4.2 m and the maximum distance from walls and partitions shall be 2.1 m. In the case of compartments containing enclosed rolling storage cabinets, the maximum area coverage shall be 9 m2 per sprinkler (see Clause 5.5.7).

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9.4.4 Maximum spacing

The maximum distance between sprinklers on range pipes and between adjacent rows shall be as follows:

(a) Sidewall sprinklers along walls ..........................................4.6 m (see also Section 5).

(b) Other sprinklers ................................................................................................4.8 m.

The maximum distance from walls and partitions shall be 2.4 m (see also Clause 5.3.2 and Clause 5.4).

9.4.5 Special sprinklers

Notwithstanding the requirements of Clause 9.4, other types of sprinklers may be incorporated in the system. Such systems shall be classified as special sprinkler systems and shall comply with the additional requirements of Clause 2.1.3.

9.5 PIPING

9.5.1 Pipe types

All system piping shall conform to the requirements of AS 4118.2.1 and Section 7.

9.5.2 Pipe sizes

Pipe sizes shall be determined by full hydraulic calculations subject to a minimum of DN 25, except that DN 20 is permitted for the connection of single sprinklers only.

9.5.3 Hydraulic calculations

Full hydraulic calculations shall be carried out in accordance with the requirements of Clause 9.2 and shall be documented in accordance with the requirements of Section 12.

9.5.4 Concealed spaces

Where concealed spaces are protected in accordance with Clause 5.6, pipe sizes to the concealed space sprinklers shall be determined by full hydraulic calculation methods. Separate calculations shall be carried out for sprinklers above and below the ceiling.

Where sprinklers above and below a ceiling share common range or distribution pipes, the flow from sprinklers above and below the ceiling need not be taken cumulatively in determining pipe size (see also Clause 5.6.3). Separate calculations shall be carried out for sprinklers above and below the ceiling. The water supply requirements of Clause 9.3 shall satisfy the greater of the calculated hydraulic demands.

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S E C T I O N 1 0 O R D I N A R Y H A Z A R D C L A S S S Y S T E M S

10.1 GENERAL

This Section specifies the requirements for the design of standard sprinkler system protection for an Ordinary Hazard class sprinkler system

10.2 DESIGN DATA

10.2.1 General

Ordinary Hazard systems shall be fully hydraulically designed to provide a flow of at least 60 L/min from each sprinkler within the design area (see Clause 1.3.8). The design area shall consist of each group of sprinklers in all parts of the building regardless of the area covered by individual sprinklers. The number of sprinklers in each design area shall be as specified in Clause 10.2.2 or Table 10.2.3, as appropriate.

10.2.2 Sprinklers under flat roofs and ceilings

The required number of sprinklers in the most unfavourable arrays shall be as follows:

(a) Ordinary Hazard 1 (OH1) ........................................................................................ 6.

(b) Ordinary Hazard 2 (OH2) ...................................................................................... 12.

(c) Ordinary Hazard 3 (OH3) ...................................................................................... 18.

(d) Ordinary Hazard 3 Special (OH3 Special) .............................................................. 30.

Each array of sprinklers shall be selected to form, as near as possible, a square, but with the longer side positioned such that it imposes the greatest hydraulic demand. The required number of sprinklers shall, where necessary to achieve the desired shape, include those sprinklers on both sides of a distribution pipe. Except as varied by this Clause, hydraulic calculation methods shall conform to the requirements of Section 12.

Where the area under consideration is separated from the remainder of the building by fire-resisting walls or drafts curtains and contains less than the required number of sprinklers, the reduced number of sprinklers shall be used in the hydraulic calculations.

10.2.3 Sprinklers under sloping roofs and in bays

Where sprinklers are installed under roofs or ceilings having a slope greater than 6°, or in bays not more than 9 m wide formed by full height walls, smoke curtains or beams more than 1 m deep (regardless of intermediate beams) or a combination thereof, the number of sprinklers in the respective arrays and the configuration of the arrays shall be as indicated in Table 10.2.3.

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TABLE 10.2.3

SPRINKLER ARRAYS UNDER SLOPING ROOFS AND IN BAYS

Number of sprinklers Hazard class

In array On longer side of array Orientation of array

OH1 8 4

OH2 15 5

OH3 24 6

OH3 Special 36 9

Longer side parallel to ridge or bay

10.3 WATER SUPPLY

10.3.1 Flow and pressure requirements

The water supply shall be capable of providing the minimum flow and pressure requirements of the system as determined by the hydraulic calculation methods described in Clause 10.2.

Where pumps are provided, they shall be capable of operating at the maximum flow rate of the system (Qmax.) (see Clause 12.9.2). NOTE: Where the flow requirements in a multistorey building at point of intersection (Qmax.) exceed 150% of the hydraulically most favourable system flow, consideration should be given to using pump suction tanks in lieu of town mains supply

10.3.2 Water storage capacity

The effective water storage capacity of a reservoir or pump suction tank dedicated as a sprinkler system supply shall comply with BCA Specification E1.5.

The storage capacity of a reservoir or pump suction tank that is the sole water source of a single water supply system may be reduced by up to two thirds for buildings up to 25 m in effective height, subject to the provision of an automatic inflow to the reservoir or pump suction tank which is sufficient for the pump to operate at the maximum flow rate (see Clause 12.9.2) for not less than 60 min.

The source and reliability of the automatic inflow shall conform to the requirements of Clause 4.1 and Clause 4.3.2.

The storage capacity of a reservoir or pump suction tank, which is part of a dual water supply system, may be reduced by one third without the provision of the automatic inflow to compensate for the reduced tank capacity.

C10.3.2 A dual water supply consisting of reservoirs or pump suction tanks provides an increased level of reliability and continuity of supply compared to a single supply. The total capacity of the dual supply provides, in normal operation, 4/3 of the required storage capacity albeit there will be a 1/3 deficit in the required storage capacity for the duration of any period during which one reservoir or tank may be out of service.

For purposes of tank refilling, the requirements of Clause 4.3.4 shall apply.

10.3.3 Additional storage capacity

The water requirement of any hydrant or other fire protection system connected to the sprinkler system water supply shall be added to the water storage capacity.

10.3.4 Pump suction tanks

Pump suction tanks shall be constructed in accordance with the requirements of Clause 4.3.4.

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10.3.5 Pressure tanks

Notwithstanding the requirements of Clause 10.3.3, the minimum quantity of water to be maintained in a pressure tank reserved entirely for sprinklers shall be a minimum of the calculated flow rate for the most unfavourable array of sprinklers for the required duration

In all other respects pressure tanks shall conform to the requirements of Clause 4.3.7.

10.3.6 Pumpsets

Pumpsets shall comply with the requirements of Clauses 4.3.8 and 4.3.9.

The duty flow and pressure of the pump(s) shall be not less than the flow and pressure calculated in accordance with Clause 10.3.1.

The minimum combined output of the pump and its supply shall satisfy the requirements of all portions of the system as required by Clause 4.3.8.4 and Figures 4.3.8.4(A) and (B).

10.3.7 Proving of water supplies

Water supplies shall be proved to meet the calculated requirements of the installed system.

Proving of water supplies shall be in accordance with the requirements of Clause 4.4.

10.4 SPRINKLERS

10.4.1 Size and type

Sprinklers shall be in accordance with AS 4118.1.1, and—

(a) have a nominal orifice size of 15 mm;

(b) be fast, special or standard response; and

(c) be pendent, upright, sidewall, flush, recessed or concealed type.

All sprinklers in any one compartment shall be of the same response characteristic, that is, fast, special or standard response (see AS 4118.1.1).

10.4.2 Maximum area coverage per sprinkler

Except for the reduced coverage required by Clause 10.4.3, the maximum area covered by sprinklers shall be as follows:

(a) Sidewall sprinklers ............................................................. 9 m2 (see also Section 5).

(b) Other sprinklers ................................................................ 12 m2 (see also Section 5).

The area covered by each sprinkler shall be defined by lines drawn midway between adjacent sprinklers at right angles to the line joining the sprinklers and by the boundary of the area covered (see Figure 12.2).

10.4.3 Reduced coverage

In cold chambers using the air circulation method of refrigeration, provender and rice mills (other than those using the pneumatic system of conveying), film and television production studios, theatres and music halls (stage protection) and compartments containing enclosed rolling storage cabinets (see Clause 5.5.7), the maximum area coverage shall be 9 m2 per sprinkler. The maximum distance between sprinklers shall be 3 m and the maximum distance from walls and partitions shall be 1.5 m.

10.4.4 Maximum spacing

The maximum distance between sprinklers on range pipes and between adjacent rows shall be as follows:

(a) Sidewall sprinklers along the walls (see also Clause 5.5) ................................. 3.6 m.

(b) Other sprinklers—

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(i) standard spacing (see Clause 5.1) ............................................................4.2 m.

(ii) staggered spacing (see Clause 5.1.3):

(A) Between sprinklers ........................................................................ 4.6 m.

(B) Between rows ................................................................................ 4.2 m.

10.4.5 Maximum distance from walls and partitions (see also Clause 5.3.2)

The maximum distance of sprinklers from walls and partitions shall be—

(a) for sidewall sprinklers from end walls ............................................................. 1.8 m;

(b) for other sprinklers ..................................................................................... 2.1 m; or

(c) half the maximum allowable design spacing, whichever is the lesser.

10.4.6 Special sprinklers

Notwithstanding the requirements of Clause 10.4, other types of sprinklers may be incorporated in the system. Such systems shall be classified as special sprinkler systems and shall comply with the additional requirements of Clause 2.1.3.

10.5 PIPING

10.5.1 Pipe types

All system piping shall conform to the requirements of AS 4118.2.1 and Section 7.

10.5.2 Pipe sizes

Pipe sizes shall be determined by full hydraulic calculations subject to a minimum of DN 25.

10.5.3 Hydraulic calculations

Full hydraulic calculations shall be carried out in accordance with the requirements of Clause 10.2 and shall be documented in accordance with the requirements of Section 12.

10.5.4 Concealed spaces

Where concealed spaces are protected in accordance with Clause 5.6, pipe sizes to the concealed space sprinklers shall be determined by full hydraulic calculation methods. Separate calculations shall be carried out for sprinklers above and below the ceiling.

Where sprinklers above and below a ceiling share common range or distribution pipes, the flow from sprinklers above and below the ceiling shall not be taken cumulatively in determining pipe sizes (see also Clause 5.6.3). The water supply requirements of Clause 10.3 shall satisfy the greater of the calculated hydraulic demands.

S

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S E C T I O N 1 1 H I G H H A Z A R D C L A S S S Y S T E M S

11.1 DESIGN DATA

11.1.1 General

High Hazard systems shall be hydraulically designed to provide an appropriate density of discharge over an assumed area of operation (number of sprinklers likely to operate) in all areas including the hydraulically most unfavourable areas of the protected building.

The design densities of discharge and the assumed areas of operation shall be as follows:

(a) Process risks as per BCA Table E1.5

(i) Design density of discharge ..................................7.5 mm/min to 12.5 mm/min.

(ii) Assumed area of operation ..................................................... 260 m2 to 360 m2.

(b) High-piled storage risks as per BCA Table E1.5

(i) Design density of discharge .................................... 7.5 mm/min to 30 mm/min.

(ii) Assumed area of operation ...................................................... 260 m2 to 300 m2 (according to density of discharge).

11.1.2 Process risks

Process risks are described in BCA Table E1.5

For process risks, density of discharge and assumed areas of operation shall be as given in Table 11.1.2.

11.1.3 High piled storage risks

High piled storage risks are described in BCA Table E1.5

11.1.3.1 General design data

The design density of discharge for high piled storage risks depends on the hazardous nature of the stock and the height of storage. High hazard class systems are only required when high piled storage exceeds the height specified in Table 11.1.3

Tables 11.1.3.2(A) and 11.1.3.2(B) establish the appropriate density of discharge and assumed area of operation according to the category, method of storage and stack height where roof or ceiling protection only is provided. Where storage fixtures are of solid or shelved construction, the requirements of Clause 5.5.9.6 shall apply.

Where an alternate wet and dry system is installed at roof or ceiling level, the assumed area of operation shall be increased by 25%.

The maximum storage heights of 7.6 m for Categories 1 and 2, 7.2 m for Category 3 and 4.4 m for Category 4 indicated in Table 11.1.3.2(A) are considered to be a limiting factor to efficient sprinkler protection where sprinklers are provided at the ceiling or roof only.

The maximum storage heights of 6.8 m for Category 1, 6.0 m for Categories 2 and 3, and 4.4 m for Category 4 indicated in Table 11.1.3.2(B) are considered to be a limiting factor to efficient sprinkler protection where sprinklers are provided at the ceiling or roof only. Where storage in racking and post or box pallets is above these heights, intermediate level protection shall be provided.

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TABLE 11.1.2

DISCHARGE DENSITY AND ASSUMED AREA OF OPERATION FOR PROCESS RISKS

Occupancy Design densitymm/min

Assumed area of operation m2

Aircraft engine testing Aircraft hangars

10.0 7.5

260 Zone protection (deluge system)

Celluloid manufacturers and celluloid goods manufacturers

12.5 260

Distilleries (still houses) 12.0 260

Electrical/electronic manufacturing and assembly (predominantly plastic components) Exhibition halls with unusually high ceilings and high concentration of combustibles

7.5

12.0

260

360

Firelighter manufacturers Firework manufacturers

10.0 10.0

260 (Note 2)

Complete deluge protection required for each building

Flammable liquid spraying Floor cloth and linoleum manufacturers Foam plastics goods manufacturers and processing Foam rubber goods manufacturers and processing

12.0 7.5

12.0

12.0

260 260 260

260

Paint and varnish works (solvent based) Plastics goods manufacturing and process works (where plastic is one of the basic materials in the operation)

7.5 12.0

260 (Note 2)

260

Resin and turps manufacturers 7.5 260 (Note 2)

Theatrical scenery store Tar distillers

10.0 10.0

260 260 (Note 2)

Vehicle repair workshops 10.0 260

NOTES: 1 Assumes use of 141°C rated sprinklers.

2 Supplementary protection by high or medium velocity sprayers, as appropriate, will be required in these risks in areas where solvents or other flammable liquids are stored or handled

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TABLE 11.1.3

MAXIMUM STORAGE HEIGHTS FOR USE OF

ORDINARY HAZARD SYSTEMS

Maximum storage height (m)

Freestanding, bin or block storage Single or double row post or box pallets and rack storage

Category of storage as

per Tables

11.1.3.2(A) and (B)

Non- encapsulated Encapsulated Non-

encapsulated Encapsulated

1 4.0 3.0 3.5 2.7

2 3.0 2.2 2.6 2.0

3 2.1 1.6 1.7 1.3

4 1.2 0.9 1.2 0.9

TABLE 11.1.3.2(A)

DISCHARGE DENSITY AND ASSUMED AREA OF OPERATION FOR HIGH-PILED STORAGE RISKS INVOLVING FREESTANDING STORAGE, BIN BOX

STORAGE OR BLOCK STACKING WHERE CEILING OR ROOF PROTECTION ONLY IS PROVIDED

Discharge density

Assumed area of operation Maximum storage height, m

mm/min m2 Category 1 Category 2 Category 3 Category 4

7.5 10.0 12.5 15.0 17.5

⎫ ⎪ ⎬ 260 ⎪ ⎭

5.3 6.5 7.6 — —

4.1 5.0 5.9 6.7 7.6

2.9 3.5 4.1 4.7 5.2

1.6 2.0 2.3 2.7 3.0

20.0 22.5 25.0 27.5 30.0

⎫ ⎪ ⎬ 300 ⎪ ⎭

— — — — —

— — — — —

5.7 6.3 6.7 7.2 —

3.3 3.6 3.8 4.1 4.4

NOTES: 1 ‘Not applicable’

2 The term ‘storage’ includes the warehousing or the temporary depositing of goods or materials while undergoing process.

3 ‘Not applicable’

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TABLE 11.1.3.2(B)

DISCHARGE DENSITY AND ASSUMED AREA OF OPERATION FOR HIGH- PILED STORAGE RISKS INVOLVING POST OR BOX PALLETS (IN SINGLE OR DOUBLE ROWS) OR PALLETIZED RACK STORAGE WHERE ROOF OR CEILING PROTECTION ONLY IS PROVIDED

Discharge density

Assumed area of operation Maximum storage height, m

mm/min m2 Category 1 Category 2 Category 3 Category 4

7.5 10.0 12.5 15.0 17.5

⎫ ⎪ ⎬ 260 ⎪ ⎭

4.7 5.7 6.8 — —

3.4 4.2 5.0 5.6 6.0

2.2 2.6 3.2 3.7 4.1

1.6 2.0 2.3 2.7 3.0

20.0 25.0 30.0

⎫ ⎬ 300 ⎭

— — —

— — —

4.4 5.3 6.0

3.3 3.8 4.4

NOTES:

1 ‘Not applicable’ 2 ‘Not applicable’ 3 Rack storage with aisles less than 1.2 m in width is treated as multiple row racks (see

Clause 11.1.3.3). 4 ‘Not applicable’

11.1.3.2 Storage in multiple row and drive-through or flow-through racks

Intermediate sprinklers shall be installed in multiple row and drive-through or flow-through racks where storage heights exceed the Ordinary Hazard limitations for post pallets and palletized rack storage exceeds two rows wide in one direction in accordance with Clause 11.1.3.4.

Rack storage with aisles less than 1.2 m in width shall be treated as multiple row racks.

11.1.3.3 Intermediate level protection in storage racks

Intermediate level protection shall be provided as indicated by the following:

(a) General Supplementary intermediate level protection shall be provided in storage racks where heights of storage exceed those given in Table 11.1.3.2(B).

Flow rates for intermediate level sprinkler protection shall be hydraulically calculated as set out in Clause 11.2.2.5.

Where racking does not exceed 3.2 m in width, one row of sprinklers shall be located centrally along the length of the rack. Where racking exceeds 3.2 m in width, but does not exceed 6 m, two rows of sprinklers shall be provided. The design of protection for racking exceeding 6 m in width shall be individually assessed. (See Figure 11.1.3.4(a), (b) and (c) for maximum spacing, stagger spacing and maximum area coverage per sprinkler.)

Whenever any rack or structural steelwork is likely to significantly interfere with water discharge from sprinklers, additional sprinklers shall be provided and taken into account in water flow calculations.

Each intermediate level sprinkler shall be fitted with a metal water shield not less than 80 mm in diameter, located immediately above the sprinkler. For sprinklers mounted upright, the shield shall not be attached directly to the sprinkler deflector. Any bracket supporting the shield shall cause minimal obstruction to the water distribution.

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Provision shall be made for the protection of piping and sprinklers against mechanical damage (see Clauses 6.9 and 7.4).

(b) Location of intermediate level sprinklers Sprinklers within racks shall be positioned so that there is not less than 150 mm clearance between the deflectors and the top of the storage in the tier immediately below the line of sprinklers.

Sprinklers shall be located in racks as follows:

(i) Category 1 or 2 goods Category 1 or 2 goods shall be protected as follows:

(A) Every alternate rack tier, but not exceeding 3.7 m from the floor to the lowest level and between successive levels.

(B) Every alternate junction of longitudinal and transverse flues or gaps between pallets.

(C) Sprinklers shall be staggered between tiers.

(D) The horizontal spacing of sprinklers within tiers shall not exceed 2.8 m (see Figure 11.1.3.4(a)).

(ii) Category 3 goods (or Categories 1 and 2 goods mixed with Category 3 goods) Category 3 goods, or Categories 1 and 2 goods mixed with Category 1 goods shall be protected as follows:

(A) Every alternate rack tier, but not exceeding 3.7 m from the floor to the lowest level and between successive levels.

(B) Every junction of the longitudinal and transverse flues or gaps between pallets.

(C) The horizontal spacing of sprinklers within tiers shall not exceed 1.4 m (see Figure 11.1.3.4(b)).

(iii) Category 4 goods (or Categories 1, 2 and 3 goods mixed with Category 4 goods) Category 4 goods or Categories 1, 2 and 3 goods mixed with Category 4 goods, shall be protected as follows:

(A) At every tier, but not exceeding 2.3 m from the floor to the lowest level and between successive levels.

(B) Every alternate junction of the longitudinal and transverse flues or gaps between pallets.

(C) Sprinklers shall be staggered between tiers.

(D) The horizontal spacing of sprinklers within tiers shall not exceed 2.8 m (see Figure 11.1.3.4(c)).

Provided that the roof or ceiling protection is not more than 3 m above the top of the stored goods, the uppermost row of intermediate level sprinklers may be omitted if this would otherwise be located at the top of the stored goods (see Figure 11.1.3.4(a), (b), (c) and (d)).

(c) The flow requirements of sprinklers within the racks shall be calculated on the assumption of an operational pressure of 200 kPa at the hydraulically most unfavourable sprinkler when—

(i) three sprinklers are operating at every sprinkler level for Categories 1, 2 and 3 goods;

(ii) two sprinklers are operating at every sprinkler level for Category 4 goods;

(iii) where rack aisles exceed 2.4 m in width, at least one rack shall be assumed to be involved;

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(iv) where rack aisles exceed 1.2 m and do not exceed 2.4 m, at least two racks shall be assumed to be involved;

(v) where racks are closer than 1.2 m (multiple row racks), at least three racks shall be assumed to be involved; and

(vi) in no case, need more than three rows of sprinklers, as seen in plan view, be assumed to be simultaneously involved at each sprinkler level.

(d) Design data for roof or ceiling sprinklers Where intermediate level sprinklers are provided—

(i) the density of discharge for the roof or ceiling sprinklers shall be appropriate to the height of storage above the highest level of intermediate level protection which can be taken from Table 11.1.3.2(B) with a minimum density of discharge of 7.5 mm/min; and

(ii) the assumed area of operation of roof or ceiling sprinklers shall be taken as—

(A) 260 m2 for wet systems irrespective of total storage height; or

(B) 325 m2 for alternate wet and dry systems

(e) The floor area controlled by a single installation of intermediate level sprinklers, shall not exceed 4000 m2 of floor area occupied by the racks, including aisles.

11.1.3.4 Bonded stores (spirituous liquors)—Rack storage

For rack storage the following parameters shall apply:

(a) General For barrel storage in racks in bonded stores, the provisions for high-piled storage risks shall be modified in accordance with Items (b) to (d) below, as appropriate.

(b) Double rack storage with aisles and walkways (see Figure 11.1.3.6(A)). The following modifications shall apply to double rack storage with aisles between and having walkways at various levels:

(i) Storage height not exceeding 9.7 m For storage heights not exceeding 9.7 m, roof or ceiling protection only is acceptable. Table 11.1.3.6 shall be used to obtain densities of discharge and assumed area of operation where storage heights exceed 7.6 m.

(ii) Storage height exceeding 9.7 m For storage heights exceeding 9.7 m, intermediate level protection shall be installed beneath walkways at intervals not exceeding 6.5 m commencing with the lowest walkway. Sprinklers under walkways shall be spaced at not more than 3.5 m and the maximum area coverage per sprinkler at each intermediate level shall not exceed 11 m2. Sprinklers at alternate levels shall be staggered in relation to the rows of sprinklers above and below.

The flow requirements of walkway sprinklers shall be calculated with an operational pressure of not less than 200 kPa at the hydraulically most unfavourable sprinkler when seven sprinklers are operating at each walkway level protected.

(c) Continuous racking without aisles or walkways (See Figure 11.1.3.6(B).) The following modifications shall apply to continuous rack storage without aisles or walkways:

(i) Storage height not exceeding 5 m For storage heights not exceeding 5 m, roof or ceiling protection only is acceptable.

(ii) Storage height exceeding 5 m For storage heights exceeding 5 m, intermediate level protection shall be installed throughout at vertical intervals not exceeding 5 m. There shall be a clear space of not less than 500 mm beneath the deflectors

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of sprinklers in intermediate level protection. Sprinklers shall be positioned over each of the line of gaps between barrel ends with a maximum spacing down each line of 7 m. The maximum area coverage per sprinkler at each intermediate level shall not exceed 7 m2. Sprinklers shall be arranged in stagger formation so that, in alternate lines, they are midway between the sprinklers in the adjacent lines. The following design data shall be used:

(A) Design density of discharge for sprinklers at intermediate levels ............................................................ 10 mm/min.

(B) Assumed area of operation at each level of intermediate protection ..............................................................70 m2.

(d) Clearance below sprinklers Clearance below sprinklers at roof or ceiling level may be reduced to 300 mm instead of the 500 mm clearance required by Clause 5.4.8.

11.1.3.5 Encapsulation

Where storage is encapsulated see (Clause 1.6.7) discharge densities listed in Tables 11.1.3.2(A) and 11.1.3.2(B) shall be increased by 50% for Category 1 and 25% for Category 2, with no increases for Categories 3 and 4. These required increases in discharge density shall also apply where intermediate sprinklers are provided.

11.1.4 Type of system

Where there is no danger of freezing, High Hazard systems shall be of the wet type. Where there is danger of freezing, a pre-action type system or alternate wet and dry system may be installed. If an alternate wet and dry system is installed at only ceiling or roof, the design area of sprinkler operation shall be increased by 25%.

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FIGURE 11.1.3.4 (in part) INTERMEDIATE LEVEL PROTECTION

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FIGURE 11.1.3.4 (in part) INTERMEDIATE LEVEL PROTECTION

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Staggered arrangement of intermediate sprinklers in double rack storage with aisles between, having walkways at various levels: maximum area per sprinkler = 11 m2

FIGURE 11.1.3.6 (A) TYPICAL BONDED STORES (SPIRITUOUS LIQUORS)

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Staggered arrangement of intermediate sprinklers in continuous racking without aisles or

walkways: maximum area per sprinkler = 7 m2

FIGURE 11.1.3.6(B) TYPICAL BONDED STORES (SPIRITUOUS LIQUORS)

TABLE 11.1.3.6

DISCHARGE DENSITY AND ASSUMED AREA OF OPERATION AT CEILING FOR BONDED STORES (SPIRITUOUS LIQUORS) RACK STORAGE

Category of storage Height of storage

Discharge density required mm/min

Assumed area of operation

m2

1

Not more than 5.3 m Above 5.3 m but not more than 6.5 m Above 6.5 m but not more than 7.6 m Above 7.6 m but not more than 8.7 m Above 8.7 m but not more than 9.7 m

7.5 10.5 12.5 15.0 17.5

260 260 260 260 260

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11.2 WATER SUPPLIES

11.2.1 Pressure and flow requirements

The pressure and flow for fully hydraulically calculated systems shall be determined by calculation (see Section 12). Installation standing pressure shall not be less than 800 kPa.

For systems designed in accordance with Tables 11.4.2.2(A) to 11.4.2.2(C), the pressure and flow shall comply with the following requirements:

(a) The water supply shall provide the flow and the corresponding running pressure given in Table 11.2.1 at the hydraulically most unfavourably situated design point in the High Hazard portion of the premises commensurate with the required density of discharge and the area of operation set out in Clause 11.1 for the particular occupancy category.

(b) Where the High Hazard portion comprises less than 48 sprinklers and the provisions of Item (d) below do not apply, the required flow and running pressure given in Table 11.2.1 shall be provided at the level of the highest sprinklers at the point of entry to the sprinkler array.

(c) Where the design area of operation is fed by more than one distribution pipe, the running pressure at the level of the highest sprinklers at the design point shall be either that given in Table 11.2.1 for the required density of discharge, or that determined by hydraulic calculation. The flow rate for each distribution pipe shall be determined on the pro-rata basis described in Item (h) below.

(d) Where the area of the High Hazard portion of the risk is less than the area of operation given in Table 11.1.3.6, 11.1.3.2(A) or 11.1.3.2(B), as appropriate, the flow rate shown in Table 11.2.1 may be proportionately reduced (see Item (h) below), but the running pressure at the level of the highest sprinklers at the design point shall be that given in the tables for the required density of discharge.

(e) Where the basic design area of operation for a given density of discharge is increased due to circumstances described under Clauses 11.1.2 and 11.1.3, the flow rate shall be proportionately increased (see Item (h) below) but the pressure at the design point shall be maintained.

C11.2.1(e) For example, in a High Hazard system with design density of 12.5 mm/min and 15 mm sprinklers, with piping conforming to Table 11.4.2.2(C) and spacing of one per 9 m2, if the flow rate was increased by 25% in accordance with Clause 11.1.3 (i.e. from 3800 L/min to 4750 L/min), the appropriate pressure requirement at the design point would be 245 kPa (see Table 11.2.1).

(f) Where the design area of operation is greater than the area of High Hazard protection, and this area is adjacent to Ordinary Hazard protection, the total flow rate shall be calculated on the basis of the rate of flow in the High Hazard portion being proportional to its area as above (see Item (h) below), and the flow in the Ordinary Hazard portion of the risk being equal to 5.0 times the balance of the area of operation. The pressure at the level of the highest sprinklers in the High Hazard portion of the risk at the design point shall be either that given in the tables for the required density of discharge or that determined by hydraulic calculation.

(g) The flow requirements specified in Items 3 and 4 of Table 11.2.1 apply only to pipe ranges that are horizontal or at a slope not exceeding 5° to the horizontal. Where the angle of 5° is exceeded, the flow requirements shall be increased by 5% for each additional 5° of slope or part thereof, and there shall be a corresponding percentage decrease in the permitted maximum period of inflow for suction tanks (see Clause 11.2.2).

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(h) The increased or decreased flow rates referred to in Item (c), (d), (e) and (f) above shall be determined on a pro rata basis according to the following equation:

1

212 a

aQQ ×= . . . 11.2

where

Q2 = flow rate required or, in circumstances described in Item (c), the flow rate in each pipe , in litres per minute

Q1 = flow rate required as given in the tables, in litres per minute

a2 = area of operation required or, in circumstances described in Item (c), the area served by each pipe, in square metres

a1 = area of operation given in the tables for the discharge density required, in square metres

(i) Where sprinklers are installed at intermediate levels in racking, all pipework, including roof or ceiling level pipework, shall be sized by full hydraulic calculation in accordance with Section 12 (see also Clauses 11.1.3.4, 11.2.2.5 and 11.4.2.6).

11.2.2 Minimum capacity of water supplies

11.2.2.1 Town main

The town main supply shall be fed from a source of at least 1 ML capacity plus the stored capacity specified in Table 11.2.2.2. Terminal mains or branch ‘dead ends’ mains of less than 150 mm in diameter shall not be used.

11.2.2.2 Reservoirs and tanks other than pressure tanks

The effective water storage capacity of a reservoir or pump suction tank dedicated as a sprinkler system supply shall comply with BCA Specification E1.5.

The storage capacity of a reservoir or pump suction tank that is the sole water source of a single water supply system may be reduced by up to one third for buildings up to 25 m in effective height, subject to the provision of an automatic inflow to the reservoir or pump suction tank which is sufficient for the pump to operate at the maximum flow rate (see Clause 12.9.2) for not less than 60 min.

The source and reliability of the automatic inflow shall conform to the requirements of Clause 4.1 and Clause 4.3.2.

11.2.2.3 Supplies not reserved entirely for sprinklers

Any private reservoir which also provides water for industrial and domestic purposes shall have a constant capacity not less than 1 ML plus the stored capacity given in Table 11.2.2.2.

NOTE: Pressure and flow tests in connection with proving the supply should be carried out when the demand for other services is at its peak.

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TABLE 11.2.1

PRESSURE/FLOW REQUIREMENTS FOR HIGH HAZARD CLASS SYSTEMS

Running pressure at the design point (48-sprinkler point) at the level of the highest

sprinklers in the High Hazard area, kPa Density of discharge Flow rate

Design spacing of sprinklers, m2

mm/min L/min 6 7 8 9

1 Systems having piping in accordance with Table 11.4.2.2(A) and 15 mm nominal sprinklers

7.5 10.0 12.5 15.0

2 300 3 050 3 800 4 500

— 180 270 380

— 240 365 520

180 315 475 675

225 390 600

2 Systems having piping in accordance with Table 11.4.2.2(B) and 15 mm nominal sprinklers

7.5 10.0 12.5 15.0

2 300 3 050 3 800 4 550

— 130 200 280

— 180 275 385

135 235 360 510

175 300 460 650

3 Systems having piping in accordance with Table 11.4.2.2(C) and 15 mm nominal sprinklers

7.5 10.0 12.5 15.0 17.5 20.0 22.5 25.0 27.5 30.0

2 300 3 050 3 800 4 550 4 850 6 400 7 200 8 000 8 800 9 650

— 70

110 160 215 280 350 435 525 620

— 95

150 215 290 380 480 590 715

70 125 195 280 380 500 630 775

— —

90 160 245 355 480 630 795

— — —

4 Systems having piping in accordance with Table 11.4.2.2(C) and 20 mm nominal sprinklers

7.5 10.0 12.5 15.0 17.5 20.0 22.5 25.0 27.5 30.0

2 300 3 050 3 800 4 550 4 850 6 400 7 200 8 000 8 800 9 650

— — — 95

125 165 205 255 305 360

— — 90

125 170 225 285 350 420 495

— —

115 165 225 295 370 455 550 650

— 95

145 210 280 370 470 575 690

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11.2.2.4 Pressure tanks

Pressure tank supplies are not acceptable for High Hazard class systems.

11.2.2.5 Supplementary sprinklers

For storage risks coming under the High Hazard class, where supplementary sprinklers are installed at intermediate levels within racking, the minimum volume of water available shall be sufficient to supply for the required duration the maximum calculated simultaneous flow for roof or ceiling sprinklers and intermediate level sprinklers for the hydraulically most favourable area (see also Clauses 11.1.3.4, 11.1.3.5 and 11.4.2.6).

11.2.3 Pumps

Pumps shall comply with the requirements of Clauses 4.10.2, 4.11, and AS 2941.

11.2.4 Proving of water supplies

Water supplies shall be proved in accordance with the requirements of Clause 4.15.

11.3 SPACING OF STANDARD SPRINKLERS

11.3.1 Maximum area coverage per sprinkler

Except for sprinklers in storage racks (see Clause 11.1.3.4), the maximum area coverage per sprinkler shall be 9 m2.

The area covered by each sprinkler shall be defined by lines drawn midway between adjacent sprinklers at right angles to the line joining the sprinklers and by the boundary of the area covered (see Figure 12.2).

11.3.2 Maximum distance between sprinklers on range pipes and between adjacent rows of sprinklers

Except for sprinklers in storage racks (see Clause 11.1.3.4), the maximum distance between sprinklers and adjacent rows shall be 3.7 m.

11.3.3 Maximum distance from walls and partitions

The distance of sprinklers from walls or partitions shall not exceed 2 m or half the design spacing whichever is the lesser (see also Clause 5.4.2).

11.4 SYSTEM COMPONENTS

11.4.1 Sprinklers

11.4.1.1 Size and type

Sprinklers shall conform to the requirements of AS 4118.1.1, and shall have a nominal orifice size of 15 mm, or 20 mm, and may be of conventional or spray type, except that intermediate level sprinklers within storage racks shall have a nominal orifice size of 15 mm.

Where sprinklers are required for building column protection in accordance with Clause 11.1.3.5, spray type sprinklers installed horizontally or side wall sprinklers installed vertically shall be used, subject to a minimum orifice size of 10 mm.

11.4.1.2 Sprinkler temperatures

In systems, with in-rack sprinklers, protecting high piled storage, 141°C temperature rated sprinklers shall be used at the roof or ceiling, and 68°C to 74°C nominal temperature rated sprinklers shall be installed within storage racks, and for column protection.

A1

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11.4.1.3 Special sprinklers

Notwithstanding the requirements of Clauses 11.4.1.1 and 11.4.1.2, other types of sprinklers may be incorporated in the system. Such systems shall be classified as special systems and shall conform to the additional requirements of Clause 2.3.3.

11.4.2 Piping

11.4.2.1 General

The appropriate sizing of piping for High Hazard systems depends on the following factors:

(a) Required density of discharge.

(b) Spacing of sprinklers.

(c) Size of sprinkler orifice used.

(d) Pressure and flow characteristics of the water supply.

To accommodate this wide range of conditions, and to provide reasonable economy in piping, systems are designed either partly by the pre-calculated pipe tables and partly by hydraulic calculation (see Clauses 11.4.2.2 and 11.4.2.3) or by full hydraulic calculation (see Section 12).

Figures 11.4.2.1(A) to 11.4.2.1(C) illustrate piping arrangements showing various design points from which the piping shall be calculated hydraulically when the pre-calculated pipe sizing tables are used.

Pipes may reduce in diameter only in the direction of flow of water to any sprinkler. An exception to this requirement is permitted in systems which are fully hydraulically calculated in accordance with Section 12.

11.4.2.2 Pre-calculated piping

Where ranges are directly connected to the distribution pipe without risers (or drops) the design point shall be taken as the last elbow, tee or branch downstream of which the 48-sprinkler array is located (see design point A in Figures 11.4.2.1(A) to 11.4.2.1(C)).

Where ranges are connected to the distribution pipe with risers (or drops), such risers (or drops) shall be considered as distribution pipes, and the design point shall be moved downstream to the point of connection of the riser (or drop) nearest the installation valves in the 48-sprinkler array (see design point B in Figures 11.4.2.1(A) to 11.4.2.1(C)).

Where the number of sprinklers in a separate array is less than the number of sprinklers for which the distribution pipes are hydraulically designed, the design point shall be taken as the point of connection of the range nearest the installation valves in such separate array.

Where single sprinklers are connected to horizontal pipes by risers (or drops), such risers shall be considered range pipes. Where such risers (or drops) exceed 300 mm in length, the horizontal pipes to which they are connected shall be sized as distribution pipes.

For complex piping arrangements requiring the use of both armpieces and risers (or drops), piping feeding such arrangements shall be sized as a combination of range and distribution pipes in accordance with Tables 11.4.2.2(A) to 11.4.2.2(C).

11.4.2.3 Hydraulic calculation of distribution piping (partly pre-calculated systems)

The distribution and rise pipe from the installation valves to the various nominal terminal points of the network, that is at each design point or at the point of entry to each sprinkler array wherever fewer than 48 sprinklers are involved (see Clause 11.2), shall be calculated hydraulically on the basis that, under the relevant flow conditions stated in Table 11.2.1, the pressure drop in this individually calculated piping will not exceed the residual pressure available from the water supply when allowance has been made for the pressure required at

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the design point in Table 11.2.1 plus the static head loss due to the height of the highest sprinkler in the High Hazard network above the installation valves.

Where the highest sprinkler of a High Hazard portion of the premises is not beyond the design point, such portion requiring the higher static head shall have its own terminating distribution pipe. The pressure loss in the distribution pipe to each section of the High Hazard risk shall be adjusted to that required either by suitably sizing the distribution pipes or by fitting an orifice plate in the feed main (see Clause 11.4.2.5) or by a combination of these two methods. The losses given in Table 11.4.2.3 shall be used for these calculations.

11.4.2.4 Hydraulic balancing of systems with orifice plates

Where it is considered necessary to fit orifice plates in order to assist in hydraulically balancing a system or to meet pump characteristic curves, the diameter of the orifice shall be not less than 50% of the diameter of the pipe into which the plate is to be fitted. Such orifice plates shall be fitted only in pipes of 50 mm diameter or larger. Orifice plates shall comply with the requirements of Appendix C.

The relationship between the size of the orifice, the flow and the pressure loss, shall be calculated on the basis of the information given in Appendix C.

11.4.2.5 Piping for supplementary protection within storage racking

Where supplementary sprinklers are installed at intermediate levels within storage racking, the piping shall be fully hydraulically calculated. In the sizing of the distribution piping, the water flow required by the intermediate sprinklers shall be added to that required by the roof or ceiling sprinklers and sprinklers protecting building columns (see Clauses 11.1.3.4 and 11.1.3.5).

Intermediate level protection within storage racks shall be controlled by a separate control assembly. Where there are not more than 50 intermediate level sprinklers they may be fed directly from roof or ceiling system distribution piping.

Where storage racks are freestanding, and the intermediate sprinklers are fed by distribution pipes attached to the building structure, the rack piping shall be connected to the distribution pipes by universal joints or flexible connections.

11.4.2.6 Sprinklers in concealed spaces

Where sprinkler protection is required in concealed spaces and under floor spaces to satisfy the requirements of Clause 5.6.1 and 5.6.2, it shall be hydraulically designed in accordance with the requirements of Section 9 (see Clauses 9.2 and 9.5).

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FIGURE 11.4.2.1 (A) TYPICAL HIGH HAZARD CLASS SYSTEM—PIPE SIZES BASED ON TABLE 11.4.2.2(A)

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FIGURE 11.4.2.1 (B) TYPICAL HIGH HAZARD CLASS SYSTEM—PIPE SIZES BASED ON TABLE 11.4.2.2(B)

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FIGURE 11.4.2.1 (C) TYPICAL HIGH HAZARD CLASS SYSTEM—PIPE SIZES BASED ON TABLE 11.4.2.2(C)

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TABLE 11.4.2.2(A)

MAXIMUM NUMBER OF SPRINKLERS ON PRE-CALCULATED PIPING FOR DESIGN DENSITIES OF DISCHARGE NOT EXCEEDING 15 mm/min

Systems with water supplies complying with the pressure and flow requirements for Item 1 in Table 11.2.1 and using 15 mm (nominal) size sprinklers.

(a) Range pipes

Ranges Nominal internal

pipe size mm

Maximum number of sprinklers permitted

on range pipes (see Note 1)

Ranges at remote end of all distribution pipes:

(i) Two end-side layouts— Last two ranges 25 32

1 2

(ii) Three end-side layouts — Last three ranges 25 32

2 3

(iii) All other layouts — Last range 25 32 40

2 3 4

All other ranges 25 32

3 4

(b) Distribution pipes

Distribution pipes Nominal internal

pipe size mm

Maximum number of sprinklers to be fed by

distribution pipe

Pipes at extremities of system 32 40 50 65 80

100

2 4 8

12 18 48 (Note 2)

Pipes between the above mentioned extremities and the installation valves (see Note 3)

To be individually calculated hydraulically in accordance with Clause 11.4.2.3

NOTES:

1 No arrangement is allowed with more than four sprinklers per range pipe. No range pipe may be connected to a distribution pipe exceeding 150 mm in diameter.

2 This requirement does not preclude the use of 100 mm pipe between the design point and the installation control assemblies if hydraulic calculation shows that this is possible.

3 The maximum length of 25 mm pipe allowed in any route from a sprinkler to the installation control assembly is 15 m including allowance for elbows.

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TABLE 11.4.2.2(B)

MAXIMUM NUMBER OF SPRINKLERS ON PRE-CALCULATED PIPING FOR DESIGN DENSITIES OF DISCHARGE NOT EXCEEDING 15 mm/min

Systems with water supplies complying with the pressure and flow requirements for Item 2 in Table 11.2.1 and using 15 mm (nominal) size sprinklers.

(a) Range pipes

Ranges Nominal internal

pipe size mm

Maximum number of sprinklers permitted

on range pipes (see Note 1)

Ranges at remote end of all distribution pipes:

(i) Two end-side layouts— Last two ranges 25 32

1 3

(ii) Three end-side layouts — Last three ranges 25 32

2 3

(iii) All other layouts— Last range 25 32 40

2 3 4

All other ranges 25 32

3 4

(b) Distribution pipes

Distribution pipes Nominal internal

pipe size mm

Maximum number of sprinklers to be fed by

distribution pipe

Pipes at extremities of system 50 (Note 2)65 80

100 150

4 8

12 16 48 (Note 3)

Pipes between the abovementioned extremities and the installation valves

To be individually calculated hydraulically in accordance with Clause 11.4.2.3

NOTES:

1 No arrangement is allowed with more than four sprinklers per range pipe. No range pipe may be connected to a distribution pipe exceeding 150 mm in diameter.

2 No distribution pipe less than 65 mm diameter is permitted for four end-side systems.

3 This requirement does not preclude the use of 150 mm pipe between the design point and the installation control assemblies if hydraulic calculation shows that this is possible.

4 The maximum length of 25 mm pipe allowed in any route from a sprinkler to the installation control assembly is 15 m including allowance for elbows.

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TABLE 11.4.2.2(C)

MAXIMUM NUMBER OF SPRINKLERS ON PRE-CALCULATED PIPING FOR DESIGN DENSITIES OF DISCHARGE UP TO 30 mm/min

Systems having water supplies complying with the pressure and flow requirements for Item 3 in Table 11.2.1 and using 15 mm (nominal) size sprinklers

OR Systems having water supplies complying with the pressure and flow requirements for Item 4 in Table 11.2.1 and using 20 mm (nominal) size sprinklers (a) Range pipes

Ranges Nominal internal

pipe size mm

Maximum number of sprinklers permitted on

range pipes (see Note 1)

End-side arrangements:

(i) Last three ranges at remote end of all distribution pipes

40 50 65

1 3 6

(ii) Other ranges 32 40 50 65

1 2 4 6

End-centre arrangements:

(i) Two end-centre systems —

(a) Last three ranges at remote end of all distribution pipes

32 40

1 2

(b) Other ranges 32 2

(ii) Three and four end-centre systems—All ranges 32 40 50

1 2 4

(b) Distribution pipes

Distribution pipes Nominal internal

pipe size mm

Maximum number of sprinklers to be fed by

distribution pipe

Pipes at extremities of system 50 (Note 2)65 80

100 150

4 8

12 16 48 (Note 3)

Pipes between the above mentioned extremities and the installation valves

To be individually calculated hydraulically in accordance with Clause 11.4.2.3

NOTES:

1 No end-side arrangement is allowed with more than six sprinklers per range pipe and no end-centre arrangement with more than four sprinklers per range pipe. No range pipe may be connected to a distribution pipe exceeding 150 mm in diameter.

2 No distribution pipe less than 65 mm in diameter is permitted for four end-side systems.

3 This requirement does not preclude the use of 150 mm pipe between the design point and the installation control assembly if hydraulic calculation shows that this is possible.

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TABLE 11.4.2.3

PRESSURE LOSSES FOR MEDIUM TUBES TO AS 1074

Loss of pressure per metre length of pipe, kPa (see Note 2) Flow rate

Nominal internal pipe size, mm

L/min 100 150 200 250

100 1 500 2 000

0.44 0.92 1.6

0.065 0.14 0.24

0.015 0.032 0.055

0.005 0.011 0.018

2 300 3 050 3 800

2.0 3.4 5.2

0.3 0.51 0.77

0.071 0.12 0.18

0.023 0.039 0.059

4 550 4 850 6 400

7.2 8.1

13.5

1.1 1.2 2.0

0.25 0.28 0.47

0.082 0.092 0.15

7 200 8 000 8 800

16.8 20.5 24.4

2.5 3.1 3.6

0.58 0.71 0.85

0.19 0.23 0.28

9 650 29.0 4.3 1.0 0.33

NOTES:

1 For heavy tubes, the losses are calculated for the appropriate flow rate from the data in Section 12. The loss of pressure at each elbow, bend or tee where the water is turned through an angle, is to be taken as equal to that incurred through 3 m of straight pipe.

2 Calculations for the ringed portions of distribution pipes should be based on these pressure losses on the total length of each pipe size multiplied by a factor of 0.14.

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S E C T I O N 1 2 H Y D R A U L I C C A L C U L A T I O N O F S P R I N K L E R S Y S T E M S

12.1 GENERAL

Section 12 details the method to be adopted in hydraulically designing sprinkler systems. This method of system design shall be adopted in selecting pipe sizes to achieve the minimum required design density within each design area (assumed number of sprinklers operating) (see Clause 12.2).

The resultant total flow and pressure demand of each design area shall not exceed the minimum available flow and pressure characteristics of the water supply.

All hydraulic calculations shall be related to the system datum point (one common geographical location). The datum point shall be as close as practicable to the source of supply, such as at the centre-line of the pump or at the town main tapping point.

This Section also details the method to be adopted in determining the maximum flow rate of the sprinkler system (Qmax.) Wherever automatic booster pumps are installed, determination of the maximum flow rate of the system is necessary to evaluate—

(a) the adequacy of the town main supply;

(b) pump suction velocity;

(c) available net positive suction head (NPSHA); and

(d) flow and pressure characteristics and power requirements of pumping units.

12.2 DESIGN AREAS (ASSUMED AREAS OF OPERATION)

In Light Hazard and Ordinary Hazard class systems, each design area is determined by selection of a specified number of sprinklers operating simultaneously (see Clauses 9.2 and 10.2).

In High Hazard class systems, each design area is defined in terms of floor area, which varies in relation to the hazard classification and/or storage arrangement (see Section 11).

The area covered by each sprinkler shall be defined by the centre-lines drawn midway between adjacent sprinklers at right angles to the line joining the sprinklers and by the boundary of the area covered (see Figure 12.2). All dimensions shall be applied in the horizontal plane.

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FIGURE 12.2 DETERMINATION OF AREA COVERED PER SPRINKLER

12.3 SPRINKLERS IN SIMULTANEOUS OPERATION

In Light Hazard and Ordinary Hazard class systems, the number of sprinklers assumed to be in simultaneous operation shall be the number nominated in Clauses 9.2 and 10.2, as appropriate. In High Hazard class systems, the number of sprinklers assumed to be in simultaneous operation shall be all sprinklers that fall within the design area, or the entire protected area, whichever is the smaller, including roof/ceiling sprinklers, in-rack sprinklers, sprinklers protecting building columns and sprinklers beneath platforms, mezzanines and obstructions etc., but excluding permitted omissions nominated in Section 11, and sprinklers installed in concealed spaces.

12.4 SPRINKLER DISCHARGE FLOW RATES

12.4.1 Light Hazard and Ordinary Hazard class systems In Light Hazard and Ordinary Hazard class systems, the minimum discharge flow rate from each sprinkler within each design area shall be as nominated in Clauses 9.2 and 10.2, as appropriate.

12.4.2 High Hazard class systems In High Hazard class systems, the discharge flow rate from each of the sprinklers at roof or ceiling level within each design area shall be sufficient to provide the minimum density of water application (design density) appropriate to the hazard classification and/or storage arrangement nominated in Section 11. For the purpose of this clause, when calculating the roof or ceiling level sprinklers, it shall be sufficient to prove that the total flow from every group of 4 sprinklers within each design area, divided by the area in square metres covered by the 4 sprinklers, is not less than the required design density, or, where fewer than 4 sprinklers are in open communication, the flow rate from each sprinkler divided by the area covered by the sprinkler, shall be at least equal to the required design density.

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The area covered by each sprinkler shall be defined by lines drawn midway between adjacent sprinklers at right angles to the line joining the sprinklers, and by the boundary of the area covered (see Figure 12.2).

In-rack sprinklers and sprinklers beneath platforms, mezzanines and obstructions, etc., shall discharge at the minimum flow rate, or at the flow rate derived from the minimum discharge pressure (as nominated in Section 11), as appropriate to the particular hazard classification and storage arrangement.

12.5 POSITION OF DESIGN AREAS

12.5.1 Hydraulically most unfavourable areas of operation

The highest pressure demands of the system are those calculated for the hydraulically most unfavourable areas of operation.

The calculated pressure demands of the hydraulically most unfavourable areas of operation determine the minimum pressure requirements of the water supply, or conversely, the minimum water supply characteristics determine the maximum pressure available for design of the hydraulically most unfavourable areas of operation.

C12.5.1 The term ‘hydraulically most unfavourable’ is not exclusive. There are frequently several hydraulically most unfavourable areas within a system, due to variations in sprinkler arrays, hazard class, range and distribution pipe diameters, roof heights, multi-level floor elevations, low-level sprinklers, in-rack sprinklers, sprinkler types and orifice sizes, etc. Many such variations can be present, scattered throughout the one sprinkler system (which often consists of several sprinkler installations), with each variation requiring calculation of a separate hydraulically most unfavourable area of operation.

Water supply pressures decline as flow rates increase. Therefore, where system flow demands vary for different areas of operation, there will be less pressure available for design of the areas with higher flow demands. In such cases it is often not only the highest pressure demand which determines the minimum acceptable flow and pressure characteristics of the water supply.

To ensure that the minimum water supply flow and pressure characteristics satisfy all pressure demands of the system, it is recommended that all calculated design area demand points be plotted when preparing the graphic representation required by Clause 12.7.

For the purpose of determining the hydraulically most unfavourable position, each design area shall be located as follows:

(a) Terminal main system with terminal range pipes At the hydraulically most unfavourable position on each distribution pipe (see Figures 12.5.1(A) and (B)).

(b) Looped main system with terminal range pipes At the hydraulically most unfavourable position on the hydraulically most disadvantaged loop (see Figure 12.5.1(C)).

(c) Gridded system with terminal range pipes At the hydraulically most unfavourable position in each of the following areas:

Between the distribution pipes—

(i) partly between the distribution pipes and partly within the area of the terminal ranges; or

(ii) wholly within the area of the terminal ranges.

(d) Gridded system without terminal range pipes At the hydraulically most unfavourable position between the distribution pipes (see Figure 12.5.1(D)).

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NOTE: Where the hydraulically most unfavourable position is not readily apparent, calculation of more than one design area may be required. The most remote area in terms of distance is not necessarily the hydraulically most unfavourable area. Proof that the hydraulically most unfavourable area has been established may be required.

FIGURE 12.5.1 (A) HYDRAULIC DESIGN—MOST FAVOURABLE AND MOST UNFAVOURABLE AREAS OF OPERATION—TERMINAL MAIN SYSTEM WITH TERMINAL

RANGE PIPES

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FIGURE 12.5.1 (B) HYDRAULIC DESIGN—MOST UNFAVOURABLE AREA OF OPERATION—ASSUMING 20 mm/min MINIMUM DISCHARGE DENSITY OVER 260 m2

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FIGURE 12.5.1 (C) HYDRAULIC DESIGN—MOST FAVOURABLE AND MOST UNFAVOURABLE AREAS OF OPERATION—LOOPED MAIN SYSTEM WITH

TERMINAL RANGE PIPES

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FIGURE 12.5.1 (D) HYDRAULIC DESIGN—MOST FAVOURABLE AND MOST UNFAVOURABLE AREAS OF OPERATION—GRIDDED SYSTEM

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12.5.2 Hydraulically most favourable areas of operation

Calculation of the hydraulically most favourable areas of operation is necessary wherever automatic booster pumps are installed.

The flow and pressure demand characteristics of the hydraulically most favourable areas of operation, when extrapolated onto the water supply flow and pressure characteristics plotted at maximum pressure, produce the maximum flow rates of the system.

For the purpose of determining the hydraulically most favourable areas of operation, the design area shall be located as follows:

(a) Terminal main system with terminal range pipes At the hydraulically most favourable position on each distribution pipe (see Figure 12.5.1(A)).

(b) Looped main system with terminal range pipes At the hydraulically most favourable position on the looped main (see Figure 12.5.1(C)).

(c) Gridded system without terminal range pipes Adjacent to the hydraulically most favourable distribution pipe (see Figure 12.5.1(D)).

(d) Gridded system with terminal range pipes Where the terminal ranges are fed from the most hydraulically favourable distribution pipe, the range pipes shall be either wholly or partially included in the design area.

C12.5.2 When extrapolating the demand characteristic curves, for the most favourable design areas, they will intersect the maximum supply curve at flow rates greater than the calculated flow rates.

Static pressure content is a critical factor when extrapolating the demand characteristics onto the supply-demand graph. The higher the static pressure content (as a proportion of the total pressure demand), the flatter the demand characteristic curve will be, which would then intersect the maximum supply curve at a much greater flow rate than the calculated flow rate.

It is not always the design area with the greatest calculated flow demand that produces the maximum flow rate of the system. As in the case of the hydraulically most unfavourable areas of operation (see Commentary C12.5.1), there are frequently several hydraulically most favourable areas of operation.

To ensure that the area generating the maximum flow rate (Qmax.) has not been overlooked, it is recommended that all calculated demand points, together with the static content within each, be plotted when preparing the graphic representation described in Clause 12.7.

12.6 SHAPE OF DESIGN AREAS

12.6.1 Hydraulically most unfavourable areas of operation

12.6.1.1 Light Hazard and Ordinary Hazard class systems

In Light Hazard and Ordinary Hazard class systems, the shape of each hydraulically most unfavourable area of operation shall be determined in accordance with the requirements of Clauses 9.2 or 10.2, as appropriate.

Where necessary, the design area shall include sprinklers on both sides of a distribution pipe.

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12.6.1.2 High Hazard class systems

In High Hazard class systems, the shape of the hydraulically most unfavourable areas of operation shall be (as near as possible) rectangular. The dimension parallel to the ranges shall be at least 1.2 times the square root of the required area of operation, except that the dimension parallel to the ranges shall be at least twice the square root of the required area of operation—

(a) where range pipes run parallel with the ridge of a roof having a slope greater than 6°; or

(b) where range pipes run along bays formed by full height walls, smoke curtains or beams more than 1 m deep, or a combination thereof, with the bays so formed, regardless of intermediate beams, being not more than 9 m wide.

Where necessary, the design area shall include sprinklers on both sides of a distribution pipe.

Where the area of the building under consideration is separated from the remainder of the building by fire-resistant walls or draft curtains and is less than the required design area specified in Clause 12.2, the design area shall be the entire area under consideration.

Where the ranges have an insufficient number of sprinklers to fulfil the 1.2 times or twice the square root of the area requirement, the design area shall be extended to include sprinklers on adjacent ranges supplied by the same distribution pipe. Where the design area is the entire sprinkler-protected area as described above, all sprinklers in the area shall be assumed to be in simultaneous operation, regardless of the number of distribution pipes supplying them.

In determining the number of sprinklers within the design area, fractions of sprinklers shall be counted as one sprinkler. All dimensions shall be applied in the horizontal plane.

In all cases, sprinklers making up the area of operation that falls outside the rectangular area shall be placed so as to maximize the hydraulic flow demand of the system, and each total area of operation shall be positioned so as to maximize the hydraulic pressure demand of the system.

Variations in sprinkler spacing, layout, elevation, range centres, sprinkler orifice sizes and pipe sizes, as well as all possible locations, shall be considered when determining the hydraulically most unfavourable areas of operation.

NOTE: See Commentary C12.5.1.

12.6.2 Hydraulically most favourable areas of operation

12.6.2.1 Terminal main system with terminal range pipes or looped main systems with terminal range pipes

In a system with terminal mains or looped mains, the shape of each hydraulically most favourable area of operation shall be (as near as possible) square. As far as is practicable, the sprinklers under consideration shall be served by one distribution pipe only.

The sprinklers assumed to be operating shall be located on each range pipe or pair of range pipes for end-centre arrays, at the hydraulically most favourable position.

Any remaining sprinklers not constituting a full range pipe or pair of range pipes shall be grouped adjacent to the distribution pipe on the next range pipe row of the area so as to maximize the hydraulic flow demand of the system. All dimensions shall be applied in the horizontal plane (see Figures 12.5.1(A) and 12.5.1 (C)).

12.6.2.2 Gridded system

In a gridded system, the shape of each hydraulically most favourable area of operation shall be (as near as possible) square.

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The sprinklers assumed to be operating shall be located on each range pipe at the hydraulically most favourable position.

Any remaining sprinklers shall be grouped on the next range pipe row of the area so as to maximize the hydraulic flow demand of the system (see Figure 12.5.1(D)).

All dimensions shall be applied in the horizontal plane.

12.7 SUPPLY-DEMAND GRAPH

12.7.1 General

A graphic representation of the complete hydraulic characteristics of the sprinkler system and each water supply shall be plotted on semi exponential graph paper (N1.85), see Figure E2. All hydraulic data plotted on the graph shall be related to the system datum point (one common geographical location), such as the centre-line of the pump or the town main tapping point.

12.7.2 Supply characteristics

Hydraulic data plotted on the graph shall include the following:

(a) The hydraulic supply characteristics of each town main supply when at minimum pressure, plus the reduced characteristics after extraction of the hydrant flow rates nominated in Clause 4.3.2.1, appropriate to the greatest hazard class present in the system.

(b) The hydraulic supply characteristics of each town main supply when at maximum pressure. These characteristics shall not be reduced by extraction of hydrant flow rates.

(c) Where pumps are installed, the manufacturer’s characteristic curve for each pumping unit, plotted only to the flow rate commensurate with the limitation of driver power.

(d) Where pumps draw from town mains:

(i) The combined (pump and town main) characteristic supply curve at minimum pressure, after reduction of the town main characteristics described in Item (a) above.

(ii) The combined (pump and town main) characteristic supply curve at maximum pressure with no reduction made for hydrant flow rates.

(iii) Where two town mains are boosted by pumps, the requirements of (d) (i) and (ii) above shall be plotted for each town main supply.

(e) Where pumps draw from pump suction tanks:

(i) The combined (pump and tank) characteristics when the stored water is at normal level (see Figure 4.3.4.2).

(ii) The combined (pump and tank) characteristics when the stored water is at low water level (see Figure 4.3.4.2).

12.7.3 Demand characteristics

Hydraulic data plotted on the graph shall include the following:

(a) The hydraulic demand characteristics of each hydraulically most unfavourable design area.

(b) The hydraulic demand characteristics of each hydraulically most favourable area of operation.

NOTE: Guidance for preparing the graphic representation described above is given in Appendix E.

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12.8 WATER SUPPLIES

Water supplies shall comply with the requirements of Section 4 and shall be capable of satisfying the flow and pressure requirements of any design area in the system, for the required duration.

For High Hazard class systems, water supplies shall comply with the additional requirements of Section11.

Where automatic booster pumps form part of the water supplies, the additional requirements of Clause 12.9 shall apply, and water supplies shall be capable of operating at not less than the maximum flow rate of the system (Qmax.) (see Clause 12.9.2).

12.9 PUMPSETS

12.9.1 General

Pumpsets shall be capable of satisfying the flow and pressure requirements of any design area, and the maximum flow rate of the system (Qmax.).

12.9.2 Maximum flow rate of the system (Qmax.)

12.9.2.1 Determination

Determination of the maximum flow rate of the system is necessary to ensure the adequacy of—

(a) flow and pressure characteristics and power requirements of pumping units;

(b) town main supplies in meeting the maximum flow rate of the system plus the hydrant flow rates nominated in Clause 4.3.2.1(c);

(c) velocity calculations in water supply connections to pumps (see Clauses 4.3.8.3); and

(d) available net positive suction head (NPSHA) (see AS 2941), as necessary for the sizing of pump suction piping.

System maximum flow rates shall be determined in accordance with the requirements of Clauses 12.9.2.2 or 12.9.2.3, as applicable.

12.9.2.2 Pumps drawing from pump suction tanks

The maximum flow rate of the pump (Qmax.) shall be assumed to occur at the point of intersection of the flow and pressure characteristics of the hydraulically most favourable area of operation producing the greatest flow rate in the system, and the pump performance flow and pressure characteristics, when the tank water is at the normal water level (see Figure 4.3.4.2).

12.9.2.3 Pumps drawing from town mains

The maximum flow rate of the pump (Qmax.) shall be assumed to occur at the point of intersection of—

(a) the flow and pressure characteristics for the hydraulically most favourable area of operation producing the greatest flow rate in the system; and

(b) the water supply flow and pressure characteristics (combined output of pump and town main), with the town main at maximum pressure.

NOTE: Where two town mains constitute a dual supply, the minimum supply characteristics will normally be from one town main and the maximum supply characteristics from the other.

12.10 CALCULATION OF PRESSURE LOSS IN PIPES

Pressure losses due to water flow through pipes shall be calculated using the Hazen–Williams equation, as follows:

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1.858

1.85 4.876.05 10QPC d

= × ××

where

P = loss of pressure per metre of pipe, in kilopascals.

Q = flow rate of water through pipe, in litres per minute.

C = roughness coefficient for the type of pipe (see Table 12.10(A)).

d = mean internal diameter of pipe, in millimetres (see Tables 12.10(B) and 12.10(C)).

Pressure losses in steel, galvanized steel, cast iron, ductile iron and copper pipes may be calculated using a simplified equation as follows:

85.1KQP =

where

P = loss of pressure per metre of pipe, in kilopascals

K = a constant of value given in Tables 12.10(B) and 12.10(C)

Q = flow rate of water through pipe, in litres per minute

TABLE 12.10(A)

DESIGN ROUGHNESS COEFFICIENT ©

Types of pipe Coefficient

Cast iron (unlined) 100

Steel (galvanized) 120

Steel (black: welded or seamless)

120

Asbestos cement 140

Concrete (bitumen lined) 140

Steel (bitumen lined) 140

Iron or steel (cement lined) 140

Copper 150

Polyethylene 150

PVC (uPVC) unplasticized 150

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TABLE 12.10(B)

MEAN INTERNAL DIAMETERS AND VALUES OF K FOR STEEL TUBE TO AS 1074

Medium Heavy

Mean (internal) diameter

Mean (internal) diameter

Nominal dia. DN

mm K

mm K

20 25 32

21.6 27.3 36.0

2.73 × 10−3

8.73 × 10−4

2.27 × 10−4

20.4 25.7 34.4

3.61 × 10−3

1.17 × 10−3

2.83 × 10−4

40 50 65

41.9 53.0 68.7

1.08 × 10−4

3.45 × 10−5

9.76 × 10−6

40.3 51.3 67.0

1.31 × 10−4

4.05 × 10−5

1.10 × 10−5

80 90* 100

80.7 93.2

105.1

4.45 × 10−6

2.21 × 10−6

1.23 × 10−6

79.1 91.6

103.3

4.91 × 10−6

2.41 × 10−6

1.34 × 10−6

125 150

129.9 155.4

4.38 × 10−7

1.83 × 10−7 128.8 154.3

4.58 × 10−7

1.90 × 10−7

* While no longer manufactured, 90 mm tube is included to facilitate calculations for existing systems involving this size.

NOTE: The values for K are based on a roughness coefficient © of 120.

TABLE 12.10(C)

MEAN INTERNAL DIAMETERS AND VALUES OF K FOR COPPER PIPES TO AS 1432

Type A Type B

Mean internal diameter

Mean internal diameter

Nominal dia. DN

mm K

mm K

20 25 32

16.2 22.1 28.4

7.34 × 10−3

1.62 × 10−3

4.77 × 10−4

17.0 22.9 29.3

5.81 × 10−3

1.36 × 10−3

4.10 × 10−4

40 50 65

34.8 47.5 60.2

1.77 × 10−4

3.89 × 10−5

1.23 × 10−5

35.6 48.3 61.0

1.59 × 10−4

3.59 × 10−5

1.15 × 10−5

80 90

100

72.0 84.7 97.4

5.14 × 10−6

2.33 × 10−6

1.18 × 10−6

72.8 85.5 98.2

4.87 × 10−6

2.22 × 10−6

1.13 × 10−6

125 150

122.8 147.0

3.83 × 10−7

1.59 × 10−7 123.6 148.2

3.70 × 10−7

1.53 × 10−7

NOTES: 1 The values for K are based on a roughness coefficient © of 150.

2 Diameters for pipes in other materials should be obtained from the manufacturers.

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12.11 PRESSURE LOSSES

12.11.1 Fittings and valves

Loss of pressure due to water flow through pipe fittings, where the direction of water flow is changed through an angle of 45° or more (other than the change of direction into a sprinkler from an elbow or tee into which the sprinkler is fitted), or through valves, shall be calculated by adding the appropriate equivalent pipe lengths given in Table 12.11.1, to the actual lengths in the network under consideration.

TABLE 12.11.1

EQUIVALENT PIPE LENGTHS FOR FITTINGS AND VALVES (APPLICABLE TO HAZEN-WILLIAMS C VALUE OF 120 ONLY)

Fittings and valves Equivalent length, m

Nominal diameter, mm

20 25 32 40 50 65 80 90 100 125 150 200 250 300

90° standard elbow 0.6 0.6 0.9 1.2 1.5 1.8 2.1 2.4 3.0 3.7 4.3 5.5 6.7 8.2

90° long radius elbow 0.3 0.6 0.6 0.6 0.9 1.2 1.5 1.5 1.8 2.4 2.7 4.0 4.9 5.5

45° elbow 0.3 0.3 0.3 0.6 0.6 0.9 0.9 0.9 1.2 1.5 2.1 2.7 3.4 4.0

Tee or cross (flow turned 90°) 0.9 1.5 1.8 2.4 3.0 3.7 4.6 5.2 6.1 7.6 9.1 10.7 15.2 18.3

Gate valve 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.6 0.6 0.9 1.2 1.5 1.8

Check valve or alarm valve (swing) — 1.5 2.1 2.7 3.4 4.3 4.9 5.8 6.7 8.2 9.8 13.7 16.8 19.8

Check valve or alarm valve (mushroom) — — — — — — — — 18.0 — 30.0 45.0 60.0 —

Check valve or alarm valve (butterfly) — — — — 1.8 2.1 3.0 — 3.7 2.7 3.0 3.7 5.8 6.4

For other values of C, the equivalent lengths shall be multiplied by factors as follows:

C Value 100 110 120 130 140 150

Factor 0.71 0.85 1.00 1.16 1.33 1.51

12.11.2 Dry pendent (or upright) sprinklers

For a dry pattern sprinkler assembly, the K factor shall be considered to apply at the entry to the sprinkler assembly with no additional allowance being made for friction losses due to flow through the sprinkler assembly dry pipe. Allowance shall be made for the static head gain or loss due to the length and orientation of the dry pipe.

12.12 ACCURACY OF CALCULATIONS

At every hydraulic junction where flows divide or join—

(a) the total flow into the junction shall equal the total flow out of the junction to an accuracy of ±2 L/min; and

(b) the pressure shall balance to within 0.5 kPa.

12.13 MINIMUM SPRINKLER DISCHARGE PRESSURE (HIGH HAZARD ONLY)

The pressure at any sprinkler, with all sprinklers discharging simultaneously within any design area, shall be not less than 50 kPa.

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12.14 MINIMUM PIPE SIZES

No distribution or range pipe shall be less than DN 25 except that DN 20 is permitted for connection to single sprinklers in Light Hazard class systems only.

12.15 VELOCITY LIMITATION

The water velocity shall not exceed 6 m/s at any valve nor exceed 10 m/s at any point in the system, for any stabilized flow condition except that these restrictions shall not apply when calculating the hydraulically most favourable areas of operation.

12.16 VELOCITY PRESSURE

Velocity pressures may be included in hydraulic calculations at the discretion of the designer. Where included, velocity pressures shall be calculated for both range pipes and distribution mains.

NOTE: The inclusion of velocity pressures in hydraulic calculations improves the predictability of the actual sprinkler system performance.

12.17 IDENTIFICATION OF FULLY HYDRAULICALLY CALCULATED SYSTEMS

A durable notice shall be fixed to the riser pipe, immediately adjacent to the control assembly, of any installation that has been hydraulically calculated. The notice shall be similar to that shown in Figure 12.17 and shall include the following information:

(a) Installation number.

(b) Installation hazard classification(s).

(c) For each hazard class within the installation—

(i) the system design requirement at the installation gauge for the most unfavourable and favourable design areas;

(ii) the system design requirement at the pump delivery pressure gauge for the most unfavourable and favourable design areas;

(iii) height of highest sprinklers above the installation gauge in the most unfavourable and favourable design area; and

(iv) height difference between installation gauge and pump delivery pressure gauge.

See also Clause 8.3 (Block Plan) for related requirements.

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Installation No. System hydraulic data

Design specification System demand

Unfavourable area Favourable area Hazard class

Area of operation

m2

Density of discharge m

m/min

Height of

highest head,*

m Flow L/min

Pressure (kPa)

installation gauge

Pump gauge

Flow L/min

Pressure (kPa)

installation gauge

Pump gauge

* Height of highest head measured from installation gauge.

The head difference between the installation gauge and the pump delivery gauge is . . . . . m.

INSTALLATION ENGINEERS

Name Address Reference number and date installed

FIGURE 12.17 ILLUSTRATION OF INSTALLATION NOTICE

(d)

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APPENDIX A ORIFICE PLATES (Normative)

A1 GENERAL

This Appendix sets out a formula to calculate the hydraulic balance of orifice plates.

Tables A1 and A2 have been produced to assist in calculating the appropriate diameter of the orifice to achieve the desired hydraulic balance required in Clauses 7.7 and Section 11.

The Tables indicate the correct orifice diameter in respect of pipe sizes from 50 mm to 200 mm for discrete values of pressure loss (Po) in kilopascals for an assumed rate of flow (Qo) in litres per minute. Table A1 (for the smaller diameter pipes) is based on a flow of 500 L/min and Table A2 (for the larger diameter pipes) is based on a flow of 5000 L/min.

The K factor referred to in the last column of Tables A1 and A2 is the constant in the following equation:

PQ=K . . . A1

where

P = pressure loss in kilopascals due to the orifice with a rate of flow of water Q L/min.

The pressure loss produced by the orifice plate is the net pressure across the orifice and not the pressure difference measured at ‘flange’, ‘corner’ or ‘D and D/2’ tapping points.

A2 REQUIREMENTS

The following requirements apply to orifice plates:

• They shall be of brass with plain central holes without burrs and of thickness specified in Table A3.

• They shall be located not less than two pipe diameters from any elbow or bend, measured in the direction of flow.

• They shall have a projecting identification tag which shall be readily visible, and on which shall be stamped the nominal pipe diameter and K factor of the orifice.

A3 NOTES ON THE USE OF TABLES A1 AND A2

To select an orifice plate that will produce a pressure loss of Px, in kilopascals, with a rate of flow of Qx, in litres per minute, calculate the value of Po from the following formulae and refer to the appropriate Tables for the correct orifice diameter (interpolate as necessary):

Pipe sizes DN 50 and DN 65: 2

500⎟⎟⎠

⎞⎜⎜⎝

⎛=

xxo Q

PP . . . A3(1)

Pipe sizes DN 80, DN 100, DN 150 and DN 200

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25000

⎟⎟⎠

⎞⎜⎜⎝

⎛=

xxo Q

PP . . . A3(2)

TABLE A1

ORIFICE PLATES FOR PIPES OF SIZE DN 50 AND DN 65 FOR A FLOW RATE OF 500 L/min

Orifice diameter, mm Pressure loss Po

Nominal internal pipe size

kPa DN 50 DN 65 K factor

250 225 200

25.9 26.5 27.1

— — —

31.6 33.3 35.4

175 150 125

27.9 28.8 29.6

— — —

37.8 40.8 44.7

100 90 80

30.9 31.1 32.2

— —

34.5

50.0 52.7 55.9

70 60 50

32.8 33.7 34.7

35.3 36.3 37.6

59.8 64.5 70.7

40 30 20

5.9 37.5 39.7

39.3 41.2 44.2

79.1 91.3

111.8

10 5

42.7 —

49.1 53.6

158.1 223.6

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TABLE A2

ORIFICE PLATES FOR PIPES OF SIZE DN 80, DN 100, DN 150 AND DN 200 FOR A FLOW RATE OF 5000 L/min

Orifice diameter, mm Pressure loss (P0)

Nominal internal pipe size

kPa DN 80 DN 100 DN 150 DN 200 K factor

3 500 3 000 2 500

41.9 43.0 44.8

— — —

— — —

— — —

84.5 91.3

100.0

2 000 1 500 1 000

46.4 48.9 52.3

— —

55.6

— — —

— — —

111.18 129.1 158.1

900 800 700

53.2 54.1 55.3

57.6 59.0 60.4

— — —

— — —

166.7 176.8 189.0

600 500 400

56.6 58.2 59.3

62.0 63.9 66.5

— — —

— — —

204.1 223.6 250.0

300 200 100

62.0 65.0 —

69.7 74.2 81.1

— 82.3 95.8

— — —

288.7 353.6 500.0

90 80 70

— — —

82.2 83.3 84.4

97.1 99.3

101.7

105.7 108.1 111.1

527.0 559.0 597.6

60 50 40

— — —

85.7 87.0 —

104.0 106.8 110.1

113.9 117.7 122.2

645.5 707.1 790.6

30 20 10

— — —

— — —

115.1 120.6

129.1 137.7 152.6

912.9 1 118.0 1 581.0

5 — — — 165.8 2 236.0

TABLE A3

ORIFICE PLATE THICKNESS

Orifice plate thickness Nominal internal pipe

size mm

DN 50 DN 65 DN 80

3 3 3

DN 100 DN 150 DN 200

6 6 6

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APPENDIX B WATER SUPPLY ARRANGEMENTS

(Informative)

This Appendix sets out examples of acceptable water supply arrangements that are considered to be reliable for the purposes of the requirements of Section 4.

Single water supplies with pumps are shown in Figure B1.

Dual supplies for high-rise buildings are shown in Figures B3 and B2.

The symbols used in Figures B1, B2 and B3 are defined in Figure B4.

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FIGURE B1 SINGLE WATER SUPPLIES WITH PUMPS

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FIGURE B2 DUAL SUPPLIES FOR HIGH-RISE BUILDINGS—TOWN MAIN AND PUMP SUCTION TANK SUPPLIES

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FIGURE B3 DUAL SUPPLIES FOR HIGH-RISE BUILDINGS—TOWN MAIN AND PRESSURE TANK SUPPLIES

FIGURE B4 SYMBOLS USED IN FIGURES B1 AND B2 AND B3

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APPENDIX C GRAPHIC REPRESENTATION OF HYDRAULIC CHARACTERISTICS

(Informative)

C1 GENERAL

This Appendix explains the methodology normally used during, and at completion of, the design process, to provide the graphic representation of the complete hydraulic characteristics of the sprinkler system, as required by Clause 12.7.

C2 THE SUPPLY-DEMAND GRAPH

A graph is essential for determination of the point where total supply meets total demand.

The graph sheet (see Figure C2) typically has its volume scale on the horizontal axis representing the flow of water in pipes, in litres per minute, to the exponent 1.85, which is the exponent used for volume in the Hazen-Williams equation (see Clause 12.10). Numerical values on this scale may be multiplied by any constant that will enable the required maximum volume to be plotted.

Increments of pressure, in kilopascals, on the vertical axis, are linear and values should be entered so as to enable the maximum supply pressure of the system to be plotted.

The advantage of the N1.85 supply-demand graph is that it enables the hydraulic characteristic curve of a piping system to appear as a straight line. Thus, only two points of the characteristic curve are required, and with a straight line drawn through these two points, the rate of flow can be determined at any residual pressure along the line, or vice-versa.

By contrast, on a graph sheet with the volume scale to the exponent 1.0, the hydraulic characteristics appear as a curve, with many calculations necessary to plot the points required to produce the curve.

All sprinkler system demand curves plot as a straight line on N1.85 graphs, however, some supply curves do not. Pump supply characteristics do not plot as a straight line, nor do the characteristics of town main and pump when combined. Also, when a constant hydrant flow is deducted from town main supply characteristics, a slight curve results.

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FIGURE C2 SUPPLY-DEMAND (N1.85) GRAPH SHEET

C3 STATIC PRESSURE AND DEMAND CURVES

An understanding of the influence of static pressure is vital for the accurate presentation of the complete hydraulic characteristics of sprinkler systems.

True static pressure is the weight of water at rest (not flowing); however, in this Standard, the term ‘static pressure’ is used in three ways, as follows:

The pressure generated from the height of still water in a gravity tank. (This is true static pressure).

The pressure in a town main, with no flow to the sprinklers or hydrants. (This is not true static pressure because the water is normally always flowing in the town main, at varying rates, due to domestic and industrial usage (see Paragraph 0)).

The pressure also varies due to fluctuations in flow at different times of the day, week or season. The static pressure available for supply to a sprinkler system should be based on the pressure available at the time of day or week or year when the domestic and industrial demand is greatest. Static pressure alone cannot be used to assess the suitability of a town main. It must always be accompanied by at least one residual pressure at a flow rate as near as possible to the maximum flow rate of the system.

The pressure difference between any two points in the system due solely to the difference in elevation between the two points.

Static (elevation) pressure demand, in kilopascals, is calculated by multiplying the difference in elevation, in metres, by 9.8. The result may be positive or negative, depending on whether the downstream point is higher or lower than the upstream point.

Whilst static pressure contributes to the total system pressure demand, it has no influence on friction loss. Friction loss is not influenced by pressure. It is dependent only on the rate of flow, diameter, length and roughness of pipe, and the number of turns in the pipework.

The total static pressure demand for a particular design area is constant, regardless of the rate of flow. It is the same at zero flow as at the calculated total flow rate of the design area.

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For instance, if the pressure-flow demand for a design area is 2000 L/min at a residual pressure of 200 kPa, and the 200 kPa residual pressure demand includes 50 kPa of static pressure, two pressure-flow characteristics are known. These are 2000 L/min at 200 kPa, and zero L/min at 50 kPa. If a straight line is drawn through these two points on the N1.85 graph, every point along the line will give another pressure-flow characteristic for that particular design area. The total static pressure contained within the total pressure demand for each design area must be entered at zero flow before the pressure-flow demand characteristics of the design area can be shown accurately on the graph.

C4 SINGLE TOWN MAIN SUPPLY

Town main supply curves are plotted onto the graph sheet to show the static pressure and residual pressures available, at various rates of flow, at a particular geographical location. Initially, this location will be at the point where the sprinkler system supply pipework connects into the town main (the tapping point). These supply characteristics descend from left to right on the graph, indicating that as flow rates increase, the available pressure decreases as a result of friction loss in the town main.

Supply curves are plotted from information collected at data recording facilities provided by the water supply authority, or from flow test results. Static pressure, plus at least one residual pressure, is necessary for plotting purposes. Two or more residual pressures, with their respective flow rates, are desirable for maximum accuracy.

When seeking town main supply characteristics, residual pressures at flow rates up to twice the expected calculated flow rate of the sprinkler system may be required to facilitate the deduction of hydrant flow requirements in accordance with Clause 4.2.3.

When more than one residual pressure is provided, the characteristic curve of a town main may not always plot in a straight line, due to fluctuations in domestic and industrial water usage occurring during the stages of data collection.

Water supply authorities normally provide pressure-flow characteristics applicable under minimum supply conditions (when pressures are at their lowest), together with a maximum ‘static’ pressure (the static pressure available when supply pressures are at their highest). Where this information is not available, flow tests must be conducted and the test results adjusted to reflect conditions under minimum and maximum supply conditions.

As there is normally always a flow to domestic and industrial water consumers serviced by the town main network, water supply authorities seldom refer to ‘static’ pressure when providing pressure/flow characteristics. The water supply authority normally provides a maximum pressure, a minimum pressure, and a series of residual pressures at various rates of flow. The series of residual pressures and corresponding rates of flow are normally applicable when the town main is under minimum supply conditions (when pressures are at their lowest). The minimum and maximum pressures given are residual pressures applicable when there is no flow occurring for fire fighting purposes, and are the pressures referred to as static pressures for the purposes of this Standard.

Where suitable infield monitoring equipment is installed by the water supply authority, it is possible to obtain a minimum pressure available for 95% of the time. This Standard permits adoption of this pressure as the minimum static pressure available for system design purposes.

Example

Given:

High Hazard class system.

Estimated calculated flow demand = 2800 L/min.

Town main supply data requested up to 6000 L/min.

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The following information is provided by the water supply authority;

1 Maximum Pressure—65.3 m head (640 kPa).

2 Minimum Pressure—49.0 m head (481 kPa).

3 Flow of 10.0 l / sec at 48.8 m residual pressure

Flow of 20.0 l / sec at 48.2 m residual pressure

Flow of 30.0 l / sec at 47.2 m residual pressure

Flow of 40.0 l / sec at 45.9 m residual pressure

Flow of 60.0 l / sec at 42.3 m residual pressure

Flow of 80.0 l / sec at 37.8 m residual pressure

Flow of 100.0 l / sec at 32.1 m residual pressure NOTE: This information has been prepared using a simulated hydraulic performance model.

4 Size and location of main: 200 mm AC main 4.6 m from South B.L. of XXX Street.

5 Based on the reduced level at the tapping point of 2.0 m (AHD).

6 Analysis of the (authority’s) infield monitoring equipment shows that a minimum residual pressure available for 95% of the time at this location is 55.2 m (541 kPa).

The above minimum and flow pressures are based on current operational data for peak consumption days and a change of demand within the supply zone would cause future variations.

The above flows are not available for general supply and are quoted for fire protection purposes. It is only in these emergencies that (the authority) is prepared to allow the water supply system to be depleted to a level below the normal operational pressures. No assumption should be made from the above as to the adequacy of the system to provide increased general supply requirements.

In the authority’s paragraph number 6, note the use of the term ‘minimum residual pressure’. Normally, a residual pressure is of value only when a related rate of flow is given; however, in the context of the total information supplied, and for the reasons given above, the pressure nominated as the minimum pressure available for 95% of the time may be considered to be the minimum static pressure for the purposes of this Standard.

The maximum supply characteristics of a town main plot parallel to the minimum characteristics (except in some rural areas, where pumps may bypass elevated tanks or reservoirs to boost pressures in the town main system). Therefore, having received all necessary minimum supply characteristics, it is necessary to obtain only the maximum static pressure of the town main. Note, however, that in the case of dual supplies, the maximum supply characteristics will not plot parallel to the minimum supply characteristics because the two sets of data will relate to alternate town mains having dissimilar pressure/flow characteristics.

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FIGURE C4 WORKED EXAMPLE OF HIGH HAZARD CLASS SYSTEM TOWN MAIN SUPPLY

The following steps are recommended for plotting of the town main characteristics, as depicted in Figure E4:

Step 1: Plot the minimum static pressure—481 kPa—at zero flow.

Step 2: Plot the minimum residual pressures given for each given flow rate.

Step 3: Draw a line intersecting all points plotted in steps 1 and 2 (Curve A).

Step 4: Plot the minimum pressure available for 95% of the time—541 kPa—at zero flow.

Step 5: Draw a line parallel to Curve A, with all points along the line being 60 kPa (541–481) above Curve A. This curve (Curve B) may be considered as the minimum supply for hydrants and sprinklers, as previously explained.

Step 6: To satisfy Clause 4.2.3, a hydrant system flow demand of 1800 L/min must be deducted from Curve B to establish the minimum pressure/flow characteristics available for the sprinkler system. At 1800 L/min, the residual pressure on Curve B is 522 kPa, therefore the first point on the new Curve C is 522 kPa at zero flow. At 2400 L/min, the residual pressure on Curve B is 507 kPa which, with a deduction of 1800 L/min will result in another point on the new Curve C of 507 kPa at 600 L/min. Continue on the same basis and then draw a line intersecting all the new points plotted. This curve (Curve C) is the characteristic curve of the minimum town main supply available for design of the sprinkler system.

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Step 7: Determine whether the minimum supply characteristics represented by Curve C are adequate for design of the sprinkler system without need of booster pumps. If they are adequate, no further information is required on the graph, other than to plot the demand points calculated for all the hydraulically most unfavourable design areas of the system. It is not necessary to plot the maximum town main supply characteristics, nor is it necessary to calculate the hydraulically most favourable design areas. If however, booster pumps will be needed, further steps are required, and Step 6 will occur later in the sequence, as detailed in the following Example 1 of Paragraph 5.

C5 PUMPS DRAWING DIRECT FROM A SINGLE TOWN MAIN SUPPLY

Where pumps draw direct from a town main, the system datum point should be located at the centre-line of the pumps. To eliminate the need for extra calculations and plotting of extra curves, pump discharge and inlet pipe manifolds should be arranged symmetrically, wherever possible.

Having determined that booster pumps are required, results of any previous hydraulic calculations should be checked to ensure that all calculated pressure/flow demands relate to the system datum point (the centre-line of the pumps) and adjusted where necessary. However, to avoid duplication of effort, hydraulic calculations should be carried out after determination of available supply characteristics.

A major initial consideration when designing the system, is the maximum pressure that will be generated when a pump is operating under closed system (zero flow) conditions, with maximum town main supply pressure applied at the pump inlet. This pressure is limited by the recommended safe working pressures of pump casings, pipework, valves and sprinklers. Consideration must also be given to system standing pressure, booster pump-start initiation pressures, jacking pump cut-in and cut-out pressures, drainage of discharge from pressure relief valves, etc. Consideration of these limitations at the initial stages of design, will assist in selection of pump duty points, and will provide design parameters for the hydraulic calculation process.

Example 1:

Given:

High Hazard Class system.

Town main characteristics are as given in Example 4.1.

Two booster pumps are required, each capable of providing independently the necessary pressure and flow.

Pump discharge and inlet manifolds are arranged so that pressure losses in pump supply and discharge pipework apply equally to each pump.

The system datum point is the centre-line of pumps.

The centre-line of both pumps is 4.2 m above the town main.

The friction loss in the connection pipe between the town main and each pump is 172 kPa at a flow of 6000 L/min.

There are two hydraulically most unfavourable design areas with the following calculated demands at the system datum point:

3150 L/min at 810 kPa, including static pressure of 220 kPa.

3280 L/min at 790 kPa, including static pressure of 210 kPa.

There are two hydraulically most favourable design areas with the following calculated demands at the system datum point:

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(A)3275 L/min at 755 kPa, including static pressure of 180 kPa.

3400 L/min at 740 kPa, including static pressure of 190 kPa.

The following steps are recommended for graphic representation of the complete hydraulic characteristics of the system, as depicted in Figures C5.1(A) and (B):

Steps 1 to 5:

Complete these steps as described in Figure C4, resulting in Curves A and B as depicted in Figure C5.1(A), and commence recording pressure-flow characteristics in tabular form, as shown in Table C5.1.

Step 6: Deduct the hydrant flow demand of 1800 L/min from all points along Curve B, to produce Curve C, in a similar fashion to the process described in Step 6 of Figure C4. Curve C represents the minimum supply characteristics available for design of the sprinkler system, applicable at the tapping point on the town main.

Step 7: Plot the demand points representing the pressure losses between the town main and the pumps. As the pumps are located 4.2 m above the town main, a static pressure loss of 41 kPa (4.2 × 9.8) must be added to the friction loss of 172 kPa between the two locations. This results in a total pressure loss of 213 kPa at a flow rate of 6000 L/min. Therefore the first point to be plotted is 41 kPa at zero flow, and the second point is 213 kPa at 6000 L/min.

Step 8: Draw a line intersecting these two points thus producing Curve D, representing the hydraulic demand characteristics of the connection pipework between the town main and each pump.

Step 9: Deduct the losses of demand Curve D from supply Curve C, to produce a new Curve E, representing the minimum town main supply characteristics available at the system datum point (the centre-line of the pumps). To avoid the confusion of the many curves that will be developed, transfer Curve E to a new graph (see Figure C5.1(B)).

Step 10: Plot the two calculated demand points for the two hydraulically most unfavourable design areas, 3150 L/min at 810 kPa, and 3280 L/min at 790 kPa onto the new graph (Figure C5.1(B)).

Step 11: Select pumps having pressure/flow characteristics that will boost the minimum town main characteristics (Curve E) at least 50 kPa above the two demand points plotted in Step 10. (This 50 kPa pressure margin is necessary to satisfy the requirements of Clause 4.2.11.4).

At the calculated flow rate of 3150 L/min, the minimum town main pressure is 330 kPa. Deduction of this pressure from the calculated demand pressure of 810 kPa leaves a balance of 480 kPa. After adding the necessary 50 kPa margin, the minimum required pump duty pressure at 3150 L/min is 530 kPa. Following the same process for the second calculated demand point, the second minimum required pump duty pressure is (790 – 320 + 50) = 520 kPa at the flow rate of 3280 L/min. For the purposes of this example, the characteristics of each of the pumps selected are depicted as Curve F in Figure C.1(B).

Step 12: Add the pressures of Curves E and F, at each of the various rates of flow, as necessary to produce the minimum combined (town main combined with pump) pressure/flow characteristics applicable at the system datum point (Curve G in Figure C.1(B)).

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Step 13: Plot the maximum town main supply characteristics applicable at the system datum point. Note that deduction of hydrant flow is not permitted when assessing the maximum pressure/flow characteristics of town mains (see Clause 12.7(B)).

Referring to the data supplied by the water supply authority, note that the maximum town main pressure of 640 kPa is 99 kPa higher than the minimum pressure of 541 kPa available for 95% of the time. Therefore, plot the maximum town main characteristics parallel to Curve D, with all points along the line being 99 kPa above Curve B. This curve (Curve H) represents the maximum town main supply characteristics applicable at the tapping point on the town main.

Step 14: Deduct the losses of demand Curve D from supply Curve H, to produce a new Curve J, representing the maximum town main supply characteristics applicable at the system datum point (the centre-line of the pumps).

Step 15: Add the pressures of Curves F and J, at each of the various rates of flow, as necessary to produce the maximum combined (town main combined with pump) pressure/flow characteristics applicable at the system datum point (Curve K in Figure C5.1(B)).

Step 16: Plot the calculated demand points for the two hydraulically most favourable design areas, 3275 L/min at 755 kPa, and 3400 L/min at 740 kPa.

Step 17: Plot the static pressures contained within the two calculated pressure demands plotted in Step 15. These are 180 kPa and 190 kPa, respectively. These are plotted at zero flow.

Step 18: Draw lines intersecting each pair of points plotted in Steps 16 and 17, and carry each line through to intersect Curve K. These curves (Curves L and M in Figure C5.1(B)) represent the demand characteristics of the two hydraulically most favourable design areas. The flow rate at the intersection of demand Curve M and supply Curve K (Point X in Figure C5.1(B)) is considered as the maximum flow rate of the system and of the pump (see Clause 12.9.2.2).

Step 19: Check the following:

(a) The minimum town main supply (Curve E) is capable of supplying the flow rate generated at the intersection of the minimum combined (town main and pump) supply curve, and the demand curves for all hydraulically most favourable design areas (Point W in Figure C5.1(B)).

(b) The pumping units have performance characteristics, including pump driver power, suitable for operation at the maximum flow rate of the system (Point X in Figure C5.1(B)) and meet the additional requirements of AS 2941 and Section 4 of this Standard.

(c) The recommended safe working pressure of the pump casing, piping, pipe fittings, valves, sprinklers, etc., is not less than the pressure generated at zero flow when the pumps are operating at maximum inlet pressure (‘pump shut-off head’—Point Y in Figure C5.1(B)). (See also Clause 4.2.1 relating to maximum permitted pressure at sprinklers).

(d) The velocity in the connection piping between the town main and the pumps does not exceed the 4.0 m/s limitation imposed by Clause 4.2.4 when a pump is operating at maximum flow rate (Point X in Figure C5.1(B)).

To assist in the collation of data and preparation of the graph, it is recommended that data be entered progressively into a table, as depicted in Table C5.1.

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FIGURE C5.1 (A) WORKED EXAMPLE OF HIGH HAZARD CLASS SYSTEM TOWN MAIN AND PUMP SUPPLY—INCLUDING HYDRANTS

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FIGURE C5.1 (B) WORKED EXAMPLE OF HIGH HAZARD CLASS SYSTEM TOWN MAIN AND PUMP SUPPLY—EXCLUDING HYDRANTS

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TABLE C5.1

DATA COLLATION TO ASSIST WITH GRAPH

A B C D E F G H J K

Flow rate

Min. town

main at tapping

95% town

main at tapping

95% town main at tapping

sprinkler only

Loss town

main to pump

95% town

main at pump

sprinkler only

Pump curve

Min. combined town main and pump

Max. town

main at tapping

Max. town

main at pump

Max. combined

town main and

pump

L/min kPa kPa kPa kPa kPa kPa kPa kPa kPa kPa

A + 60 -1800 L/min C - D E + F B + 99 H -D J + F

0 481 541 523 41 482 602 1 084 640 599 1 201

600 478 538 510 45 465 604 1 069 637 592 1 196

1 200 472 532 494 50 444 596 1 040 631 581 1 177

1 800 463 523 475 56 419 581 1 000 622 566 1 147

2 400 450 510 453 72 381 563 944 609 537 1 100

3 000 434 494 430 89 341 539 880 593 504 1 043

3 600 415 475 405 113 292 505 797 574 461 966

4 200 393 453 375 132 243 454 697 552 420 874

4 800 370 430 — — — — — — — —

5 400 345 405 — — — — — — — —

6 000 315 375 — — — — — — — —

Note also, where the two pumps have differing pressure-flow characteristics (as will often occur when one is electric motor-driven, and the other is diesel engine-driven) it will be necessary to plot separate curves (F, G and K) for each pump.

Where three pumps are proposed, any two of which are capable of providing, in aggregate, the necessary pressure and flow, the two characteristic curves can be combined horizontally. That is, at any given pressure, the flow rates can be combined.

If three pumps, with identical performance characteristics, were to be used in the previous Example 1 of Paragraph 5, and each pump was capable of providing half the flow rate commensurate with the pressures given in column F of Table C5.1, any two of the pumps operating simultaneously in parallel, would provide the pressure-flow characteristics of Curve F in Figure C5.1(B).

The flow rates at any given pressure can also be combined where pumps with dissimilar characteristics are operating in parallel.

Example 2:

Given:

(a) Three pumps are to be installed, any two of which are to be capable of providing, in aggregate, the necessary flow and pressure requirements of the system.

(b) Pumps Nos 1 and 2 have identical pressure-flow characteristics. Pump No. 3 is dissimilar, with lesser pressure-flow characteristics.

(c) The pressure flow characteristics of the pumps are as shown below.

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Task:

To determine the minimum and maximum performance characteristics of any combination of two pumps operating in parallel.

Recommended Procedure:

Step 1: Plot the manufacturer’s individual pump performance curves onto a graph (Figure C5.2).

Step 2: Prepare a table of flows and pressures (see Table C5.2), reading off the graph the flow rates applicable to individual residual pressures. 50 kPa increments of pressure are used to simplify the plotting process.

Step 3: Plot the combined flow rates at the applicable residual pressures onto the graph (see Figure C5.2).

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TABLE C5.2

COMBINING PUMP CURVES

Each of pumps

Nos 1 and 2

Pump No. 3

Pumps Nos 1 and 2 combined

Pumps Nos 1 and 3 combined Pressure

kPa Flow

L/min Flow

L/min Flow

L/min Flow

L/min

890 1 000 0 2 000 1 000

855 2 900 1 600 5 800 4 500

850 3 000 2 000 6 000 5 000

800 4 000 3 500 8 000 7 500

750 4 700 4 200 9 400 8 900

700 5 200 4 650 10 400 9 850

650 5 500 4 970 11 000 10 470

600 5 700 5 200 11 400 10 900

FIGURE C5.2 WORKED EXAMPLE COMBINING PUMP CURVES

Where three pumps are installed, as described above, hydraulic calculations should incorporate provision for two system inlet points and the pump performance characteristics applicable at each inlet point. If this is not possible, hydraulic calculations should be based on the total demand flow rate being supplied to, and discharged from, the pump at the hydraulically most disadvantaged location, notwithstanding the fact that the pump is discharging less than the total demand flow rate.

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C6 DUAL TOWN MAIN SUPPLIES

Where dual supplies, involving two separate town mains, are required, the minimum characteristics of both should be obtained. When pumps are necessary to boost inadequate town main pressures, the maximum static pressure applicable to each town main supply is also required. The characteristics of the two sets of test data relating to minimum supply conditions, should be examined carefully, and the worst supply characteristics should be plotted for design and review purposes.

Similarly, when booster pumps are installed, the two maximum supply characteristics should be examined, and the supply giving the greater maximum residual pressure at or near to the maximum flow rate of the system, should be plotted. In this situation, the maximum supply characteristics of one town main will not normally plot parallel to the minimum supply characteristics of the other, as they are separate supplies with dissimilar characteristics.

This procedure applies to separate town mains, and also when dual sprinkler system supply connections are taken from a single town main, with a stop valve fitted on the town main between the two sprinkler supply branches. The minimum and maximum supply characteristics should be applicable to the town main reticulation each side of the stop valve, on the basis that the stop valve will be closed at the time of system operation.

Example

Given:

High Hazard class system.

Estimated calculated flow demand for the hydraulically most unfavourable design area = 3750 L/min.

Dual supplies are required.

Pressure losses from each tapping point to the sprinkler system, are equal (see Column D, Table C6.1).

The water supply authority provides the following test data, applicable at the tapping points on the town main, based on the stop valve being closed.

Town Main No. 1 (TM1) Town Main No. 2 (TM2)

Minimum static 730 kPa Minimum static 730 kPa

Maximum static 870 kPa Maximum static 880 kPa

Flow L/min

Residual pressurekPa

Flow L/min

Residual pressure kPa

1200 725 1200 726

2400 700 2400 717

3600 657 3600 690

4800 623 4800 663

6000 565 6000 637

7200 500 7200 597

8000 450 8000 570

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The water supply authority is unable to supply minimum pressures available for 95% of the time.

The following steps are recommended for plotting of the town main characteristics, as depicted in Figure C6(A).

Step 1: Plot the minimum characteristics of both town mains, and develop Curves A and B as shown in Figure C6(A).

Step 2: To establish the minimum supply pressure available after deduction of the required hydrant flow provision, add 1800 L/min to the estimated calculated flow rate for the hydraulically most unfavourable design area (3750 + 1800) = 5550 L/min. At this rate of flow, the available pressure on Curve A is 585 kPa. If this pressure is insufficient for design of the system, booster pumps are required, and the system datum point will move to the centre-line of the pumps. Go to Step 5 if pumps are required.

Step 3: If booster pumps are not required, a hydrant system flow demand of 1800 L/min must be deducted from Curve A to establish the minimum pressure/flow characteristics available for the sprinkler system.

At 1800 L/min, the residual pressure on Curve A is 715 kPa, therefore the first point on new Curve C is 715 kPa at zero flow. At 2400 L/min the residual pressure on Curve A is 700 kPa which, with a deduction of 1800 L/min, will result in another point on new Curve C of 700 kPa at 600 L/min. Continue to deduct 1800 L/min from Curve A on the same basis, then draw a line connecting all the new points plotted. This curve (Curve C in Figure C6(A)) is the characteristic curve of the minimum town main supply available for design of the sprinkler system.

Step 4: Confirm that the minimum supply characteristics represented by Curve C are adequate for the design of the sprinkler system without need of booster pumps. If these characteristics are adequate, it will not be necessary to plot maximum town main characteristics, nor will it be necessary to hydraulically calculate the hydraulically most favourable design areas of the system. Complete all hydraulic calculations and plot the demand points for the hydraulically most unfavourable design areas. No further information is required on the graph.

NOTE: Steps 5 to 17 are necessary only when pumps are required to boost town main pressures. The progressive tabulation of pressure-flow characteristics, as shown in TABLE C6, will be of assistance in development of graphs.

Step 5: Note that the greatest residual pressures are provided from Town Main No. 2. Note also that the maximum static pressure of 880 kPa for Town Main No. 2 is 150 kPa above the minimum pressure of 730 kPa. Draw a line parallel to Curve B, with all points along the line being 150 kPa above Curve B. This curve (Curve C) represents the maximum town main supply characteristics available at the town main tapping point (see Figure C6(B)).

Step 6: A hydrant system flow demand of 1800 L/min must be deducted from Curve A to establish the minimum pressure/flow characteristics available for the sprinkler system (see Clause 4.2.3). At 1800 L/min, the residual pressure on Curve A is 715 kPa, therefore the first point on new Curve D is 715 kPa at zero flow. At 2400 L/min the residual pressure on Curve A is 700 kPa which, with a deduction of 1800 L/min, will result in another point on new Curve D of 700 kPa at 600 L/min. Continue on the same basis, then draw a line connecting all the new points plotted. This curve (Curve D) is the characteristic curve of the minimum town main supply available for design of the sprinkler system. Note the figures in bold type in columns A and D of Table C6, which indicate the

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value of tabulating the figure in this manner.

Step 7: Calculate the static and friction pressure losses incurred between the town main and the centre-line of the pumps. In this example the total loss at 8000 L/min is 220 kPa, including 80 kPa static pressure. Plot these demand points to produce Curve E, as shown in Figure C6(B).

Step 8: At various rates of flow, deduct the pressure losses in Curve E from Curve D to produce Curve F. This curve represents the minimum town main supply characteristics available at the centre-line of the pumps (the system datum point), after deduction of the hydrant flow rate of 1800 L/min.

Step 9: From Curve C, deduct the losses incurred between the town main and the pumps (Curve E), to produce Curve G, representing the maximum town main supply characteristics applicable at the centre-line of the pumps. Note that hydrant flow provisions must not be deducted from the maximum town main supply characteristics (see Clause 12.7.1(d)(B)).

Step 10: Pump selection. When selecting pumps, consideration should be given to the maximum standing pressure of the system and the maximum pressure generated when a pump is operating in a closed system condition with town main supply at maximum pressure. Working backwards from the maximum acceptable system standing pressure will usually provide a guide to pump selection.

Note that Curves F and G have been carried forward to a new graph (Figure C6(C)) with the horizontal flow scale multiplied by a lower constant to magnify the graphic representation of the system.

For the purposes of this example, Curve H, in Figure C6(C), represents the pressure-flow characteristics of the pumps selected.

Step 11: Add the pressures of Curve H to those of Curve F, at rates of flow as necessary to produce the characteristic curve of the minimum combined (pump and minimum town main) Curve J in Figure C6(C).

Step 12: Add the pressures of Curve H to those of Curve G, at rates of flow as necessary to produce the characteristic curve of the maximum combined (pump and maximum town main) Curve K in Figure C6(C).

Step 13: Complete all necessary hydraulic calculations for the hydraulically most unfavourable design areas, ensuring that a 50 kPa margin is maintained between design area pressure demands and all points along Curve J, in accordance with the requirements of Clause 4.2.11.4. For the purposes of this example, hydraulic calculations have resulted in the following system demands at the system datum point for the three hydraulically most unfavourable design areas, each having a static pressure content of 200 kPa;

3750 L/min at 775 kPa; 3675 L/min at 785 kPa; and 3450 L/min at 818 kPa.

Step 14: Plot these demand points on the graph, and plot the static content of 200 kPa at zero flow. Draw a line through the two points representing the demand characteristic curve of each hydraulically most unfavourable design area.

Step 15: Complete the hydraulic calculations for the hydraulically most favourable design areas. For the purposes of this example, hydraulic calculations result in the following demands:

3825 L/min at 595 kPa including 150 kPa static pressure.

3850 L/min at 640 kPa including 150 kPa static pressure.

3875 L/min at 675 kPa including 120 kPa static pressure.

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Step 16: Plot all demand points on the graph, including the static pressure content included in each total pressure demand. Draw a line through the two points representing the demand characteristic curve of each hydraulically most favourable design area and extend the lines to intersect the maximum combined supply curve (Curve K). Curve M in Figure C6(C) represents the demand characteristics of the design area producing the greatest rate of flow at the intersection point. The flow generated at the intersection of Curves M and K is the maximum flow rate of the system, and of the pumps, for the purposes of this Standard.

Step 17: Check the following:

The pressure-flow characteristics plotted on the graph to indicate the interaction between supply and demand curves, are those applicable at the system datum point.

That there are no other hydraulically most unfavourable design area demands affecting the minimum pressure requirements for pump selection.

That there are no other hydraulically most favourable design area demands which might intersect the maximum combined supply curve at a greater rate of flow.

The minimum town main supply (Curve F) is capable of supplying the flow rate generated at the intersection of the minimum combined (town main and pump) supply curve and the demand curves for all hydraulically most favourable design areas (intersection of Curves M and J).

The pumping units have performance characteristics, including pump driver power, suitable for operation at the maximum flow rate of the system (intersection of Curves M and K in Figure C6(C)) and meet the additional requirements of AS 2941 and Section 4 of this Standard.

The recommended safe working pressure of the pump casing, piping, pipe fittings, valves, etc., is not less than the pressure generated at, or near, zero flow when the pumps are operating at maximum inlet pressure (see also Clause 4.2.1 relating to maximum permitted pressure at sprinklers).

The velocity in the connection piping between the town main and the pumps does not exceed the 4.0 m/s limitation imposed by Clause 4.2.4 when pumps are operating at maximum flow rate (intersection of Curves M and K in Figure C6(C)).

To assist in the collation of data and preparation of the graph, it is recommended that data be entered progressively into a table, as depicted in Table C6.

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FIGURE C6 (A) WORKED EXAMPLES—PLOTTING OF TOWN MAIN CHARACTERISTICS

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FIGURE C6 (B) WORKED EXAMPLES—PLOTTING OF BOOSTED TOWN MAIN CHARACTERISTICS

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FIGURE C6 (C) WORKED EXAMPLES—DETERMINATION OF MAXIMUM FLOW RATES

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TABLE C6

DATA COLLATION TO ASSIST WITH GRAPH

A B C D E F G H J K

Flow rate

Min. town main

No. 1 at tapping

Min. town main

No. 2 at tapping

Max. town main

No. 2 at tapping

Min. town

main at tapping

sprinkler only

Loss town main

to pump

Min town main

No. 1 at pump

sprinkler only

Max town main

No. 2 at pump

Pump curve

Min. combined

(town main

No. 1 + pump)

Max. combined

(town main

No. 2 + pump)

Flow rate

L/min kPa KPa kPa kPa kPa KPa kPa kPa kPa kPa L/min

B + 150 -1800 L/min D 0 − E C − D F + H G + H

0 730 730 880 715 80 635 800 440 1075 1240 0

600 728 729 879 700 83 617 796 457 1074 1253 600

1200 725 726 876 682 85 597 791 465 1062 1256 1200

1800 715 720 870 657 90 567 780 457 1024 1237 1800

2400 700 717 867 645 97 548 770 435 983 1205 2400

3000 682 701 851 623 101 522 750 412 934 1162 3000

3600 657 690 840 595 110 485 730 372 857 1102 3600

4200 645 683 833 565 123 442 710 331 773 1041 4200

4800 623 663 813 530 133 397 680 290 687 970 4800

5400 595 653 803 500 148 352 655 230 582 885 5400

6000 565 637 787 465 163 302 624 — — — 6000

6600 530 612 762 425 177 248 585 — — — 6600

7200 500 597 747 — — — 550 — — — 7200

7800 465 580 730 — — — 515 — — — 7800

8000 450 570 720 — 220 — 500 — — — 8000

C7 HIGH-RISE SYSTEMS WITH BOOSTED TOWN MAIN SUPPLIES

Systems with design areas at widely differing elevations present a special problem due to the disparity between the amounts of static pressure contained within the total pressure demands of the design areas at the highest and lowest elevations. This disparity results in the pressure-flow demand of the design area at the lower elevation plotting substantially lower on the graph, with the demand curve intersecting the maximum supply curve at a proportionally greater rate of flow compared to low-rise systems.

The effects of these static pressure disparities are illustrated in the following example:

Example

Given:

Multistorey residential building.

Sprinkler flow rate—260 L/min, common to the hydraulically most unfavourable design area on each floor level.

Elevation difference between sprinklers at the top and the bottom of the pressure stage is 37.8 m.

Elevation difference between highest sprinklers in the pressure stage and the centre-line of pumps is 55 m.

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Demand at top of riser is 260 L/min at a residual pressure of 250 kPa.

In the event that booster pumps are required—

two identical units will be installed side by side, each capable of providing independently the necessary flow and pressure demands of the system; and

the pump discharge and pump inlet piping manifolds should be arranged so that pressure losses in pump supply and pump discharge pipework will apply equally to each pump and so that each pump will automatically boost either of the two separate town main supplies.

Town main characteristics are as follows:

Town Main No.1 Town Main No.2

Min. static pressure

519 kPa Min. static pressure

600 kPa

Max. static pressure

680 kPa Max. static pressure

719 kPa

Flow Residual pressure Flow Residual pressure

(L/min) (kPa) (L/min) (kPa)

300 467 300 604

600 510 600 593

900 499 900 583

1200 485 1200 571

The water supply authority is unable to provide minimum pressures available for 95% of the time.

The following steps are recommended for graphic representation of the system:

Step 1: Plot the minimum town main supply characteristics. These are obviously the pressure-flow characteristics given for Town Main No. 1. Draw Curve A as depicted in Figure C7(A) and Table C7.

Step 2: A hydrant flow rate of 600 L/min should be deducted from Curve A to establish the minimum pressure-flow characteristics available for the sprinkler system (see Clause 4.2.3). At 600 L/min on Curve A, the residual pressure is 508 kPa, therefore the first point on new Curve B is 508 kPa at zero flow. At 700 kPa on Curve A, the residual pressure is 504 kPa; therefore, another point on new Curve B is 504 kPa at 100 L/min. Continue on the same basis to develop Curve G, representing the minimum town main supply characteristics available at the tapping point on the town main. This hydrant flow deduction process is more easily carried out using a tabular recording method, as depicted in Table C7.

Step 3: Calculate the pressure loss between the tapping points on the town mains, and the centre-line of the pumps. For the purposes of this example, at a flow rate of 1200 L/min, the losses are as follows:

Town Main No.1 to pumps—185 kPa including 39 kPa static pressure—plot and draw as Curve C.

Town Main No.2 to pumps—140 kPa including 39 kPa static pressure—plot and draw as Curve F.

Plot these demands and draw Curves C and F, as shown in Figure C7(A) and Table C7.

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Step 4: Deduct the pressures on Curve C from Curve B, at various flow rates, to develop Curve D. This curve represents the minimum town main supply characteristics available for the sprinkler system, at the system datum point (the centre-line of the pumps).

Step 5: Plot the maximum town main supply characteristics. As the maximum static pressure available from Town Main No. 2 is 119 kPa higher than the minimum static pressure for Town Main No. 2, add 119 kPa to each residual pressure given for Town Main No. 2, then plot and develop Curve E, as shown in Figure C7(A) and Table C7.

Step 6: Deduct the pressures on Curve F from Curve E at various flow rates, to develop Curve G. This curve represents the maximum town main supply characteristics applicable at the system datum point.

Step 7: Develop a new graph with a horizontal scale multiplied by a lower constant to magnify the graphic representation of the system. Carry forward Curves D and G (see Figure C7(A)).

Step 8: Calculate the highest pressure demand at the pump at the required system flow demand of 260 L/min. For the purposes of this exercise, the friction loss between the pump and the top of the rising main is 32 kPa. Add the 250 kPa demand at the top of the riser, and the static pressure required to lift the water 55 m. The total demand is therefore [250 + 32 + (55 × 9.8)] = 821 kPa at 260 L/min at the system datum point (the centre-line of the pumps). Plot this point and the static demand of 539 kPa, and develop demand Curve L. This curve represents the demand characteristics of the hydraulically most unfavourable design area of this particular pressure stage.

Step 9: Establish the minimum pump duty point. At 260 L/min, the minimum town main pressure at the system datum point is 450 kPa. Deduct this from the total demand pressure of 821 kPa, leaving a balance of 371 kPa. Add the required 50 kPa margin (see Clause 4.2.11.4), giving a minimum pump duty point of 260 L/min at 421 kPa. For the purposes of this exercise, Curve H in Figure C7(B) represents the pressure-flow characteristics of the pumps selected. Note that the selected pumping units will operate to a maximum flow rate of 450 L/min only.

Step 10: Add the static and residual pressures of Curves D and H at common flow rates as necessary to produce the characteristic curve of the minimum combined (pump and minimum town main), shown as Curve J in Figure C7(B).

Step 11: Add the static and residual pressures of Curves G and H at common flow rates as necessary to produce the characteristic curve of the maximum combined (pump and maximum town main), shown as Curve K in Figure C7(B).

Step 12: Calculate the pressure-flow demand of the hydraulically most favourable design area in the pressure stage. For the purposes of this exercise, this demand is 270 L/min at 425 kPa, applicable at the system datum point. The sprinklers in the hydraulically most favourable design area are 17.2 m above the pumps, therefore the total demand pressure of 425 kPa incorporates 168 kPa of static pressure.

Step 13: Plot the two points for the hydraulically most favourable design area demand characteristics (168 kPa at zero flow, and 425 kPa at 270 L/min), and draw Curve M through these points and intersecting Curves J and K.

Step 14: Check that the minimum town main supply (Curve D) will continue to supply at the flow rate generated at the intersection of Curves M and J.

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Step 15: Check that the maximum combined supply (pump and maximum town main) Curve K, intersects with Curve M. In Figure C7(B), Curve K does not extend sufficiently to intersect with Curve M, due to the characteristic curve of the pumps (Curve H) terminating at a flow rate of 450 L/min.

Step 16: Select alternative pumps, or increase pump driver power, as necessary to ensure that the maximum combined supply curve intersects the hydraulically most favourable design area demand curve. (See broken line extension to Curves H, J and K). The flow rate at the intersection point is 490 L/min and is considered as the maximum flow rate of the system, and of the pumps, for the purposes of this Standard (see Clause 12.9.2.2).

Step 17: Check the following:

(a) That pressure-flow characteristics plotted on the graph to indicate the interaction between supply and demand curves, are those applicable at the system datum point.

(b) That there are no other hydraulically most unfavourable design area demands affecting the minimum pressure requirements for pump selection.

(c) That there are no other hydraulically most favourable design area demands which might intersect the maximum combined supply curve at a greater rate of flow.

(d) That the minimum town main supply (Curve D) is capable of supplying the flow rate generated at the intersection of the minimum combined (town main and pump) supply curve and the demand curves for all hydraulically most favourable design areas (intersection of Curves J and M).

(e) That the pumping units have performance characteristics, including pump driver power, suitable for operation at the maximum flow rate of the system (intersection of Curves M and K in Figure C7(B)) and meet the additional requirements of AS 2941 and Section 4 of this Standard.

(f) That the recommended safe working pressure of the pump casing, piping, pipe fittings, valves, sprinklers, etc., is not less than the pressure generated at, or near, zero flow when the pumps are operating at maximum inlet pressure (see also Clause 4.2.1, relating to maximum permitted pressure at sprinklers).

(g) That the velocities in the connections between the town mains and the pumps do not exceed the 4.0 m/s limitation imposed by Clause 4.2.4 when pumps are operating at maximum flow rate (intersection of Curves M and K in Figure C7(B)).

To assist in the collation of data and preparation of the graph, it is recommended that data be entered progressively into a table, as depicted in Table C7.

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FIGURE C7 (A) WORKED EXAMPLE— MULTISTOREY RESIDENTIAL BUILDING

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FIGURE C7 (B) WORKED EXAMPLE—MULTISTOREY RESIDENTIAL BUILDING—

COMBINED (PUMP AND MAXIMUM TOWN MAIN) SUPPLY CURVE

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TABLE C7

DATA COLLATION TO ASSIST WITH GRAPH

A B C D E F G H J K

Flow rate

Min. town

main No. 1 at

tapping sprinkler

& hydrant

Min. town main

No. 1 at tapping

sprinkler only

Loss town main

No. 1 to pump

Min. town

main at pump

Max. town main

No. 2 at tapping

Loss town main

No. 2 to pump

Max. town main

No. 2 at pump

Pump curve

Min. combined

(town main No. 1 + pump)

Max. comb. (town main

No. 2 + pump)

L/min kPa kPa kPa kPa kPa KPa kPa kPa kPa kPa

B − C E − F D + H G + H

0 519 508 39 469 719 39 680 459 928 1139

100 518 504 42 462 718 42 676 464 926 1140

200 517 500 45 455 717 45 672 447 902 1119

300 516 496 48 448 716 50 666 419 867 1085

400 514 492 56 436 715 55 660 377 813 1037

450 340

500 511 488 68 440 712 60 652

600 508 485 80 405 710 65 645

C8 PUMPS DRAWING FROM PUMP SUCTION TANKS

There are only two static pressures to consider where pumps draw from pump suction tanks. One is the pressure generated when tanks are at maximum capacity, the other when tanks are at minimum capacity. This makes the process of graphical representation less complex, however, the calculation of minimum pump suction pipe diameters is a little more complicated.

Example

Given:

High Hazard class system.

Two full capacity tanks are provided, each with the maximum effective water level 4.3 m above the centre-line of the pumps.

The system datum point is the centre-line of the pumps.

The centre-line of the pumps is 918 mm above the minimum effective water level in the tanks.

The pump suction and the pump discharge manifolds are arranged symmetrically, so that pump inlet and outlet pressures are the same, whichever of the two pumps is operating.

Calculated demands for the hydraulically most unfavourable design areas are as follows:

5600 L/min at 890 kPa including 180 kPa static pressure.

5800 L/min at 870 kPa including 165 kPa static pressure.

Calculated demands for the hydraulically most favourable design areas are as follows:

(i) 5900 L/min at 597 kPa including 79 kPa static pressure.

(ii) 6100 L/min at 570 kPa including 110 kPa static pressure.

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Step 1: The pressure losses in the pump suction pipework must be deducted from the pump performance characteristics to show the true supply pressures at the system datum point when stored water is at the low water level. For the purposes of this example, the friction loss in the pump suction pipework, at a flow rate of 5600 L/min, is 16 kPa, based on the pump and tank furthest apart.

As the centre-line of the pumps is 918 mm above the minimum effective water level, a static pressure loss of 9 kPa also applies, so the total demand at 5600 L/min is 26 kPa. Plot these two points on the graph, and draw Curve A (see Figure C8). Note that the pressure scale has been magnified on the right side of the graph to facilitate more accurate readings from Curve A. Read the pressures at various rates of flow and enter them into a table (see column A in Table C8).

Step 2: Select pumps on the basis that 26 kPa will be deducted from the pump curve to compensate for the loss in the suction piping, and a 50 kPa pressure margin is required to satisfy the requirements of Clause 4.2.11.4. Therefore the selected pump curve must have a residual pressure of at least 966 kPa (890 + 76) at the calculated flow rate of 5600 L/min. For the purposes of this exercise, pumps are selected with pressure-flow characteristics as represented by Curve B in Figure C8, and column B in Table C8.

Step 3: Deduct the losses incurred in the suction pipework (Curve A) from the pump characteristics (Curve B) at various flow rates, to produce Curve C, representing the minimum supply characteristics at the system datum point. This is facilitated by the development of column C in Table C8.

Step 4: Develop a characteristic curve representing the maximum supply characteristics at the system datum point, which will apply when tank storage is at high water level. As the maximum effective water level is 4.3 m above the centre-line of pumps, a static pressure of 42 kPa will apply as an addition to the static pressure and all residual pressures along Curve C. Develop column D in Table C8, and Curve D in Figure C8.

Step 5: Plot the demand points for the hydraulically most unfavourable design areas and check to ensure that there is a pressure margin of at least 50 kPa between each demand point and Curve C.

Step 6: Plot the demand points for the hydraulically most favourable design areas and draw the demand curves (see Curves E and F in Figure C8). Note that Curve F intersects Curve D at a flow rate of 8200 L/min. This is the maximum flow rate of the pumps and of the system for the purposes of this Standard (see Clause 12.9.2.2).

Step 7: Check the following:

(a) The pumping units have performance characteristics, including pump driver power, suitable for operation at the maximum flow rate of the system and meet the additional requirements of AS 2941 and Section 4 of this Standard.

(b) All hydraulically most unfavourable design area calculated pressure demands are at least 50 kPa below the minimum supply curve (see Curve C).

(c) There are no additional hydraulically most favourable design areas with demand curves which may intersect Curve D at a flow rate greater 8200 L/min.

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(d) The recommended safe working pressures of pump casings, pipe, fittings, valves, sprinklers, etc., is not less than the maximum pressure generated at or near zero flow.

(e) Suction pipework complies with the requirements of Clause 4.2.11.3 and AS 2941. An explanation of the procedures necessary for checking suction pipework compliance is given in Step 8.

Step 8: This step is necessary to check that the suction piping complies with the requirements of Clause 4.2.11.3 and AS 2941. Note that AS 2941 requires suction piping to be sized such that, with pumps operating at maximum flow rate (as defined in Step 6 above), the net positive suction head available (NPSHA) at the pump inlet, should be at least 1.0 m in excess of the net positive suction head required (NPSHR). AS 2941 also states that NPSHA should be reduced by 0.1 m for each 100 m above sea level at the pump centre-line. NPSHR is shown on the manufacturer’s pump performance characteristic graph, and rises as flow rates increase. For the purposes of this exercise, the NPSHR for the selected pumps is 5.6 m at the maximum flow rate of 8200 L/min, and the centre-line of the pumps is 50 m above sea level. Reading from Curve A in Figure C8, the friction loss in the suction pipe is 33 kPa (42 – 9), or 3.367 m head.

NPSHA is calculated using the following equation:

NPSHA = Ps + Pa − Pv − Pf

Where:

Ps = suction head measured from the low water level ‘x’ (see Clause 4.2.9.2) to the pump centre-line (negative values apply for suction lift).

Pa = absolute atmospheric pressure (m), assumed to be 10.45 m at sea level.

Pv = vapour pressure (m) assumed to be 0.239 m at 29 degrees C.

Pf = friction loss in suction pipework (m).

Therefore the NPSHA for this example is calculated as follows:

Ps = 0.918 m; Pa = 10.4 m (10.45 – 0.05); Pv = 0.239 m; Pf = 3.367 m.

NPSHA = 0.918 m + 10.4 m – 0.239 m – 3.367 m = 5.876 m.

As the minimum required NPSHA is 6.6 m, the system is unacceptable.

To solve the problem of inadequate NPSHA, several options are available, including selection of alternative pumps having a lower NPSHR. Generally however, the best solution is to increase the diameter of part, or all, of the suction pipework. The NPSHA calculated above, is 0.724 m (7.1 kPa) too low, therefore the previous friction loss of 33 kPa must be reduced to no more than 25.9 kPa at the flow rate of 8200 L/min. For the purposes of this exercise, an increase in diameter of part of the suction pipework results in a total friction loss of 24 kPa (a total loss of 33 kPa at 8200 L/min including 9 kPa static pressure).

Note that Curves C and D will plot higher on the graph due to lower losses in the suction pipework, and it will be necessary to re-check the items listed in Step 7 and to re-calculate the NPSHA.

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In this instance, a recheck of NPSHA results in the following:

The maximum flow rate of the system increases to 8260 L/min

The loss in the suction pipe increases to 33.5 kPa. After deduction of the 9 kPa static pressure content, the friction loss is 24.5 kPa, which equates to 2.5 m head.

Re-applying the equation: 0.198 m + 10.4 m − 0.239 m − 2.5 m = 6.743 m which is 1.143 m above NPSHR of 5.6 m; therefore, the revised system is acceptable.

FIGURE C8 WORKED EXAMPLE—PUMPS DRAWING FROM PUMP SUCTION TANKS

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TABLE C8

DATA COLLATION TO ASSIST WITH GRAPH

With original suction pipe With revised suction pipe

A B C D

A B C D

Flow rate

Loss in suction

Pump curve

Min. supply

Max. supply Flow

rate Loss in suction

Pump curve

Min. supply

Max. supply

L/min kPa kPa kPa kPa L/min kPa kPa kPa kPa

B − A C + 42 B − A C + 42

0 9 980 971 1013 0 0 980 971 1013

1200 10 995 985 1027 1200 10 995 985 1027

2400 12 1006 994 1036 2400 11 1006 995 1037

3600 16 1006 990 1032 3600 14 1006 992 1034

4800 22 990 968 1010 4800 18 990 972 1014

5600 26 975 949 991 5600 21 975 954 996

6000 27 965 938 980 6000 22 965 943 985

7200 36 936 900 942 7200 28 936 908 950

8400 44 897 853 895 8400 34 897 863 905