Disclosure to Promote the Right To Information

Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, in order to promote transparency and accountability in the working of every public authority, and whereas the attached publication of the Bureau of Indian Standards is of particular interest to the public, particularly disadvantaged communities and those engaged in the pursuit of education and knowledge, the attached public safety standard is made available to promote the timely dissemination of this information in an accurate manner to the public.

इंटरनेट मानक

“!ान $ एक न' भारत का +नम-ण”Satyanarayan Gangaram Pitroda

“Invent a New India Using Knowledge”

“प0रा1 को छोड न' 5 तरफ”Jawaharlal Nehru

“Step Out From the Old to the New”

“जान1 का अ+धकार, जी1 का अ+धकार”Mazdoor Kisan Shakti Sangathan

“The Right to Information, The Right to Live”

“!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता है”Bhartṛhari—Nītiśatakam

“Knowledge is such a treasure which cannot be stolen”

“Invent a New India Using Knowledge”

है”ह”ह

IS 4308 (2003): Specification for Dry Chemical Powder forFighting B and C Class Fires - [CED 22: Fire Fighting]

Apri l 2003

IS 4308 : 2003

~~

m3tTx m etc11 xi 31f1';:f~ cfi ~ ~1i:f)

~ QI'3'S'( --~

( C[JRT :rmerur )

Indian Standard

Reaffirmed 2008

DRY CHEMICAL POWDER FOR FIGHTINGBAND C CLASS FIRES SPECIFICATION

(Second Revision)

ICS 13.220.10

© BIS 2003

BUREAU OF INDIAN STANDARDS MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG

NEW DELHI 110002

Price Group 7

AMENDMENT NO. 1 APRIL 2005TO

IS 4308: 2003 DRY CHEMICAL POWDER FORFIRE FIGHTING BAND C CI.JASS FIR~:S ­

SPECIFICATION( Second Revision )

( Foreword. para 3, Lines 6 and 7 ) ~ Substitute 'bi-carbonates of alkalimaterials and potassium chloride' for 'sodium bicarbonate. potassiumbicarbonate, potassium chloride etc."

( Page I, clause 4.3.1 ) - Add the following at the end of clause:

'Chemical content of the dry powder shall be determined as per Annex D."

( Page 2. clause 4.6.2.1, line 9 )~ Delete '27 ± SoC'.

[Page 8. clause 4.12.I.3(c)) - Substitute '2.8 kN/m2, for' 276 kN/m 2, .

( Page 8, Fig. 6 ) ..- Substitute '364 nun' jOr '363.5 mrn' am '4> 7.5REGULATING V AL VE' for '<1> 75 REGtIT...ATING VALVE' .

( Page 9, Fig. 7 ) - Substitute the figure given on page 2 for the existing:

Amend No.1 to IS 4308 : 2003

--------e-r330·0

-_t--- 254.0----1

PLAN

ELEVATION SIDE VIEW

All dimensions in millimetres.

FIG. 7 FIRE PAN (STAfNLESS STEEL SHEET 2.24 mm)

( Page 9~ Fig. 8, Note) - Insert the following Note below the existing:

NOTE - The diameter of vertical cylindrical portion mounted onto (he puffer chamber

shall be as follows:

Inner diaOUlCrdia

51.4 mm.and57.6 nun.

2

Amend No.1 to IS 4308 : 2003

( Page 13 ) -- Insert the following Annex at the end of the committeecomposition:

ANNEXD(Clause 4.3.1 )

DETERl\1INATION OF CHEMICA L C()NTENT

D-l PROCEDlJRE .~.~. For the determination of chemical contents of drypowder, following procedure shall be followed.

0-1.1 Remove sihcone by suitable. solvent.

D-t.2 Weigh approximately 2 g of sample of dry powder and add 250 mldistilled water and mix it. If required, heal for solubility.

D-l.3 Add 2··3 drops of bromocresol green indicator. Colour of sample solutionshall become blue.

D-I.4 Fill burette with I N sulphuric acid and start titration. In the end samplesolution shall become colourless.

D-l.5 Note the reading of sulphuric acid used for titration.

D-2 CALClJLATION

where

Percentage of chemica!\/x Nx ALWt

M

v :;:;; volume in ml of sulphuric acid required for titration,N :;.;: normality of sulphuric acid. andM =: mass in g of sample.

«~ED 22 )Reprography Unit. 81S. New Delhi. India

3

AMENDMENT NO.2 MAY ·2006TO

IS 4308 : 2003 DRY CHEMICAL POWDER FOR FIREFIGHTING B AND C CLASS FIRES - SPECIFICATION

( Second Revision)

( Amendment No.1, see pages 1 and 3 ) - Substitute the following forexisting Annex D :

ANNEXD( Clause 4.3.1)

DETERMINAnON OF CHEMICAL CONTENT

0-1 COMPOSITION

D-l.l Sodium or Potassium Bicarbonate Content

D-l.1.1 General - TIlls method is intended to determine the bicarbonatecontent of sodium bicarbonate or potassium bicarbonate dry chemical fireextinguishing agents which may contain waterproofing and fluidizing agents andother materials required for satisfactory performance. This method assumes thatall bicarbonate is present as the sodium salt or the potassium salt, as applicable.

D-l.1.2 Apparr':» -- The following apparatus shall be used:

A -- Analytical balance, capable of weighing accurately to 1 mg;

B- Aluminiwn moisture dishes, 65 mm diameter x 44.5 mm high withclosely fitting slip-over cover.

C - Glass desiccators - one containing 95 to 98 percent by mass reagentgrade sulplmric acid as a drying agent or eaCh /silica gel; anothercontaining molecular sieves or 'Drierite' as a dry agent;

D -- Oven, capable of operating in the range of 250°C; and

E - Sodium bircarbonate or potassium bicarbonate reagent.

D-1.t.3 Procedure - Heat a clean, capped aluminimn moisture dish in an ovenat 250°C for 30 min, transfer quickly to a desiccator containing 'Driente' ormolecular sieves. Allow contents to cool to room temperature, then weigh thecapped dish quickly to 0.1 mg. This is the tare mass of the dish.

1

Amend No.2 to IS 4308: 2003

D-l.1.4 Transfer 25 to 3 g of sample into the aluminium moisturedish, weighto the nearest 0.1 mg, and place separatedcap and container in a desiccatoroversulphuric acid. Dryto constant mass. This mass, less the tare mass of the dish,is thedry samplemass.

D-l.1.5 Heat the capped moisturedish with the dry sample in an oven at 25°Cuntil loss in massbecomesconstant (16 h or overnight has been found suitable).Every time the hot. capped moisture dish is removed from the cover to checkprogress of In3SS loss, it shall bequickly transferred to a disiccator containingfresh 'Drierite' or molecular sieves as the dryingagent. After cooling to roomtemperature, the capped moisturedish must be weighed to an accuracy of ± O. 1mgas quickly as possible.

D-l.l.6 Sampling, drying, heating and cooling conditions, and weighingtechnique shall be verified as necessary, using reagent grade sodiumbicarbonate, or potassium bicarbonate, in place of the dry chemical fireextinguishing agent sample. A value over 99.0 percent NaHC03 for reagentsodium bicarbonate, or over 99.0 percent kHC03 for reagent potassiwnbicarbonate, shallconstitute verification of the test procedure.

D-1.1.7 Calculation - Calculate the percentage of sodium bicarbonate, orpotassium bicarbonate, in the dry sample as:

aPercentage NaHC03 ;:: -b- x 270.9

or . aPercentagekHe03 = -b- x 322.8

where

a =: loss of mass in g, after heating the sample at 25°C, and

b == the dry samplemassin g.

(CED22 )

ReprographyUnit. BIS, New Delhi. India2

AMENDMENT NO.3 AUGlJST 2007TO

IS 4308 : 2003 DRY CHEMICALPOWDER FOR FIGHTING BAND C CLASS

FIRES - FIGHTING

(Second Revision)

(Page J, clause 4.3.I.fiflh line):

a) Substitute 'minimum' for 'more than' before 90 percent.

b) Delete last sentence 'The allowed -------- constituents'.

(CEO 22)

Reprography Unit, I3IS, New Delhi, India

AMENDMENT NO.4 NOVEMBER 2008TO

IS 4308 : 2003 DRY CHEMICAL POWDERFOR FIGHTING BAND C CLASS

FIRES - SPECIFICATION

( Second Revision)

(Amendment No.2, Annex D, page 1, clause D-l.1.3, line 4) - Substitute'1 mg'for'O.l mg'.

(Amendment No.2, Annex D, page 2, clause D-l.1.4, line 2) - Substitute'I mg' for '0.1 mg'.

(Amendment No.2, Annex D, page 2, clause D-1.1.5, line I) - Substitute'250°C' for '25°C'.

(Amendment No.2, Annex 0, page 2, clause D-1.1.7, line 7) - Substitute'250°C' for '25°C'.

(CEO 22)

Reprography Unit, BIS, New Delhi, India

Fire hghting Sectional Committee, eED 22

FOREWORI)

This Indian Standard (Second Revision) was adopted by the Bureau of Indian Standards, after the draft finalizedby the Fire Fighting Sectional Committee had been approved by the Civil Engineering Division Council.

Fire fighting dry chemical powder meeting this standard is used in dry chemical powder fire extinguishers, fixedinstallations and mobile fire tenders for fighting Classes 1:3 and C tires. However, dry chemical powder forfighting A, Hand C fires are covered under IS 14609 : 1999 'Specification for dry chemical powder for fightingA, Band C Class fires' and tire involving reactive metals that is, Class D fires as also radioactive metals arcseparately covered under IS 4R61: 19X4 'Dry powder for fighting fires in burning metals (firs! revisions",

The efficiency of dry chemical powder for extinguishments is governed by its physical properties and chemicalcomposition. Purticlc SJ/l' of the powder is an important characteristic which determines its tire knock downpropcrt ic s and keeping qualities when used ill extinguishers. As very fine particle arc carried away with flamedraft, fine particles have better fire knock down properties hut cannot he easily projected out, the coarse particlesarc also allowed to achieve better ballastic properties. Therefore fine and coarse powder particle must he balancedwhile manufacturing this powder. The dry chemical powder i~ generally composed of basically sodium bicarbonate,potassium bicarbonate, potassium chloride, etc, with additives to make it water rcpcllant, free flowing andconforming to various requirements of this standard. While selecting the various raw materials for the manufactureof this dry chemical powder, It shall be ensured that these arc non-toxic, non-corrosive, non-abrasive andclectricallv non-conductive.

In the following situations, the application of dry powder covered in this standard should not be consideredsatisfactory:

a) Fires involving chemicals containing their own oxygen supply such as cellulose nitrate, etc;

b) Fires involving radio-active metals such as radium uranium, polonium, etc;

c) Area where residual deposits of the powder may adversely affect electronic cquipments or delicateelectrical relays: and

d) Fire involving combustible metals such as alkali metals, magnesium titanium, zirconium, etc.

This standard is formulated to provide guidance regarding selection ormaterials and requirements in regard to

the quality of dry powder used for Class Band C fires. This revision incorporates procedures for particle sizedistribution determination, hygroscopicity, moisture content and guidance notes for usc of this powder. Therequirements for hygroscopicuy and caking, free flow characteristics, foam compatibility and tire knock downproperties have been modified apart from general updation. The various tests for Class Band C fires incorporatedin this standard are based on the studies conducted at the Defence Institute of Fire Research, New Delhi and al...taking into consideration the International Standards such as ISO, EN, UL, etc.

Till: composition of the Committee responsible for the formulation of this standard is given at Annex C.

For 1he purpose of deciding whether a particular requirement of this standard is complied with, the final valueobserved or calculated, expressing the result ofa test or analysis, shall be rounded offin accordance with IS 2 : 1960. Rules for rounding offnumerical values (revised)', The number of sign iiicant places retained in the rounded offvalue should he the same as that of the specified value in this standard.

IS 4308 : 2003

Indian Standard

DRY CHEMICAL POWDER FOR FIGHTINGBAND C CLASS FIRES - SPECIFICATION

( Second Revision)

J SCOPE

This standard lays down the requirements of drypowder for use as extinguishing medium for fightingClass 13 and C fires.

2 REFERENCES

The standards given in Annex A contain provisionswhich through reference in this text, constituteprovisions of this standard. At the time of publication,the editions indicated were valid. All standards aresubject to revision and parties to agreements based onthis standard are encouraged to investigate thepossibility of applying the most recent editions of thestandards given at Annex A.

J TYPES

The dry chemical powder shall be ordinary orcompatible with all types of foams covered underIS 49X4 (Parts 1, 2 and 3). The test requirements forfoam cornpatihility are given in 4.11.

4 QlJALITATIVE REQlJlRE!\1ENTS

4.1 The sample ofdry powder lor testing shall be drawnin such a manner that it represents the entire strata ofpowder from any container and shall be tested forproperties mcnrioned in the following clauses.

4.2 Apparent ()ensity

The apparent density of the dry chemical powder whendetermined by the method given in 4.2.1 shall beI .t: 0.15.

4.2.1 A sample of 100 ± I g of the dry powder shall beplaced in a clean, dry 250 ml, stoppered glass graduatedmeasuring cylinder having an approximate height of

320 mrn and approximate internal diameter of 40 mill.Secure the stopper in cylinder. Rotate the cylinder forte n complete revolutions, slowly at a ratc ofapproximately I revolution every 2s. Immediately afterthe tcn revolutions have been completed. set thecylinder upright on a level surface and allow thepowder to settle for ) SO s. Read off the volumeoccupied by the powder and calculate the apparent

density from the following equation:

Apparent density I OO/volull1e of powder in 011

4.3 Chemical Content

4.3.1 The declared chemica! content uf the drychemical powder need not include constituent makingup less than 10 percent by mass of the extinguishingpowder. However, the chemical content declared shallcover more than 90 percent of basic material of totalcomposition of the extinguishing powder. The allowedtolerance shall not exceed :i. 3 percent of the declinedvalue for constituents.

4.4 Particle Size Distribution

4.4.1 When tested as per IS 1607 the particle sizedistribution shall be as given in Table I.

Table 1 Base Characteristics

(Clause 4.4.1)

SI rartide Slze Minimum MaximumNo. (Percent Retained on)(I) (2) (3) (4)

I) 0.425 mm/40 mesh sieve 0 0II) \) 1",0 111111/ I UO mesh SIC"l' ()

iii) 0.075 rl1Jw200 1l1(.....h sieve 0 \0

iv) 0.045 mm/325 mesh sieve 10 35v) Haltom pan 53 90

NOTE ~. The duration of sieving shall he 3o nun for handsieving and 10 min for machine sieving.

4.5 Hygroscopichy

4.5.1 A sample of dry chemical powder shall bedeemed to have met the requirement of hygroxopicityif the percentage gain in mass due to moistureabsorption docs not exceed 1.5 percent.

4.5.2 Procedure

Weight accurately 109 of dry chemical powder in a250 1111 beaker. Keep the beaker in a desiccator atXO percent relative humidity obtained using standardglycerin water mixture. Take the weight of the beakerafter 48 h. Increase in weight shall be noted andpercentage hygroscopicity shall be culcu luted asfollows:

Percent hygroscopicity __ Increase in wci~ht of sarnpl~. Original weight of sample

IS 4308 : 2003

4.6 Caking Test

4.6.1 Procedure

Take 100 g of powder in a 250 ml beaker and store thebeaker in an atmosphere having relative humidity92 percent at 27 ± 2°C for a period of6 h. Then transferthe same to a desiccator containing sulphuric acid(9X percent w/w H2S04 ) for a period of24 h. Observethe formation of any caking or lump in the powder. Incase there is any caking or lump formation, allow it todrop from a height of 200 mrn un a smooth hardS 1I r fa c e. The Iu III P S haJJ be f r jab let0 pas s therequirements given in 4.4.1.

4.6.2 Resistance tv Caking. Lumping and Hardness ofth« Caking

A sample of dry chemical powder shall be deemed tohave passed the test if the penetration of the needle isfound more than 15 nun.

The resistance of the dry chemical powder to cakingand lumping shall be determined by preparing thesamples as described in 4.6.2.1 and using a suitablepenetrometer as specified in 4.6.2.2 and operating itas per instructions contained in 4.6.2.3. Determine thepenetration distance three times at three non-collinearpoints across the surface of the dry powder fireextinguishing agent on each of the two samples.Determine the arithmetic mean and report the same asthe penetration distance.

-t.ft.2. J Sample preparation

Place 100 g: sample of powder in a nickel crucibleshaped cup of suitable capacity. Similarly prepareanother sample. Mount both the cups on a suitable sieveshaker in holders and subject the powder to vibrationsuntil there is no further compaction observed. but inany event for not less than 5 min.

TV GON TU BING

AIR ..IN -r:...... ~

Expose the sample to humid atmosphere by keepingthem in a moving air stream humidifier described inFig. I at 27 ± 5°C and minimum 78 percent relativehumidity for 24 h. followed by drying for 24 h bykeeping in a electric oven maintained at 4g ± 3°e .

NOTE _.~ Stagnant air conditions found in the usual saturatedsolution desiccator compartments may not give consistent resultsand precautions shall be taken to ensure air circulation if adesiccator is used as the humidifier. A 250 mm internal diameterdesiccator with a saturated ammonium chloride solution in thetower compartment may be used in this dctcrminauon. Duringthe lest. circulate air at 5 l/rnin. Pre-saturate the arr by bubblingthrough distilled water and then through a saturated ammoniumchloride solution and introduce into the desiccator through acentre tube having an internal diameter of fl nun, terminating20 mm above the centre in the desiccator porcelain round plate.Check the relative humidity of the exit air stream from time totime using some convenient means,

4.6.2.2 Equipment

The penetration apparatus (see Fig. 2) consists of apenetrometer (see Fig. 3) with a needle in a holder(spindle) able to move vertically without measurablefriction and capable of indicating the depth ofpenetration to the nearest 0.1 mrn. The mass of thespindle shall be 47.5 1: 0.05 g and the total mass ofneedle and spindle assembly 50.0 -±: 0.05 g.

The needle shall he made of fully hardened andtempered stainless steel. It shall be approx imately50 mill in length and 1.02 mrn in diameter.symmetrically tapered at one end by grinding to a conehaving an angle between R.7° and 9.7° for the entirecone length. The cone shall be coaxial with the straightbody of the needle. The total axial variation of theintersection between the conical and straight surfacesshall not exceed 0.2 111n1. The truncated tip of the coneshall be within the diameter limits of0.14 and 0.16 n1l11

and square to the needle axis within 2°. The entire edgeof the truncated surface at the tip shall be sharp and

I ....~---+GLASSTUBING

FIG. I MOVING AIR STREAM HUMIDIFYING AI)PARATUS

2

IS 430H : 2003

KNOB TO SET DIALAT ZERO

CIRCULAR __.....DIAL

GRADUATED

NEEDLE

SAMPLECUP

SAMPLECUP PLATE

SAMPLETUB

FI(i. 2 TI'ST ARRAN(ir.MEN"l HlR HYGROSCOPIC! TY AND CAKING TEST

~RACK

It is designed to measure in mrn and tenths uf a mmthe penetration of the needle, permanently fixed in abrass ferrule which in turn is held at the lower end ofa vertically movable spindle which is made to fallfreely without friction under the gravitational force intodry chemical powder held in a cup that has beencompacted and exposed to humid atmosphere followedby drying as specified.

Before letting the spindle fall down, it is held in staticposition in a guide against a spring loaded button. Inorder to let the assembly of needle, ferrule and spindlefall down the spring loaded button has to be pressedand kept pressed for 5 s. The penetration, that is, the

free of burrs. The surface roughness height of thetapered cone surface shall be 0.2 to 0.3 micronsarithmetic average. The needle shall be mounted in astainless steel made ferrule and the exposed lengthbeing between 40 to 45 mm. The ferrule shall be1.2 1: 0.05 mm in a diameter and 38 ± I mm in length.The needle shall be rigidly mounted in the ferrule. Themass uf the ferrule needle assembly shall be2.50 ± 0.05 g.

4.6.2.2.1 Penetrometer

F 11'1I£ ADJUSTMENTSCREW

.:::::oI~a--~'---~SPIRIT LEVEL

FIG. 3 PENETROMETFR

SPINDLE -----

3

IS 4308 : 2003

distance the spindle, needle and ferrule assembly hastravelled down is manually measured by using amovable rack and fixed pinion arrangement havinga pointer fixed on the axle of the pinion. This pointeris fixed at the centre of a circular graduated dial.

When the upper end of the vertical rack is manuallypressed. the pointer rotates over a circular dial havingequal divisions graduated from 0 to 400.

4.6.2.3 Operating instructions for penetrometer

a) Ensure that the needle made of stainless steelis rigidly and permanently fixed in a brassrod called ferrule.

h) Loosen the screw provided on the lower endof the spindle. Insert the brass ferrule of thepenetration needle into the needle holdercalled spindle and tighten the screw so thatneedle may not corne out duringmeasurements.

c) Level the penetrometer by suitably rotatingthe three levelling screws provided on thebase and seeing the air bubble of the spiritlevel provided on the base so that air bubbleshould rest in the centre of the spirit level.

d) By keeping the button pressed manually raisethe spindle, that is, the needle holder withneedle and ferrule assembly till the upper flatend of the spindle touches the lower end ofthe rack made of square rod of brass.

c) Loosen the small knob provided on the leftof the graduated circular dial and manuallysliding it up or down and tightening, that is,by manipulating the screw set the dial suchthat pointer reads 400 (or zero).

f) Keep the cup holding the caked samplepowder on the base of the penetrometer inthe centre.

g) Holding the arc shaped arm loosen theL-shapcd bolt. Now lower the arc shaped ann(spindle and needle assembly) tell thetruncated tip of the needle remains say 10 mrnabove the surface of the dry powder. Nowscrew up the L-shaped bolt.

h) Loosen the screw provided on the left side ofarm and rotate the fine movement adjustmentscrew provided on the right side of the arcshaped arm.

By moving the fine movement screw systemattached to the ann in anti-clockwise directionas seen from above, the needle gets loweredand vice-versa, that is, by moving the finemovement screw the clockwise direction thelevel of needle goes up. Adjust the finemovement screw till the truncated tip of the

4

needle just touches the upper surface of thecaked powder sample held in the cup.

j) Now press the spring loaded button for 5 s torelease the assembly of needle, ferrule andspindle and let this assembly ofneedle, ferruleand spindle fall freely under the earth'sgravitational force. It is essential that this fallof needle should take place without friction.

k) After releasing the button when the downwardmovement of needle and spindle assemblystops. Note the distance the needle haspenetrated into the dry powder sample as readon the dial by manually pressing with thumbat the upper end of the square ended rack tillthe lower end of the rack touches the upperflat end of the spindle.

4.7 Water Repellency Test

4.7.1 Procedure

Dry powder weighing 50 g shall be placed in a taredthat is clean dry and weighed beaker and graduallyfilled with 50 ml of distilled water. After 2 min, thedry powder and the water from the beaker shall begently poured out and the beaker with wet powder, ifany sticking to the beaker. dried in an oven at 60°C for2 h and then cooled in a desiccators containinganhydrous calcium chloride for I h. The beaker shallthen be weighed and the weight of dry residuecalculated. The increase in the weight of the beakerdue to powder residue sticking to the beaker shall notexceed 0.75 g that is 1.5 percent.

4.8 Moisture Content

4.8.1 The moisture content shall not exceed0.25 percent (m/m).

4.8.2 In an atmosphere of 50 ± 5 percent relativehumidity and a temperature of27 ± 5°C, place a sampleof approximately 50 g for 6 h into a tared aluminiumdish having 65 mrn diameter and 15 mrn depth andweigh accurately. Place the dish holding powder. samplein a desiccator using 95 to 98 percent by mass reagentgrade sulphuric acid as a drying agent. Maintain theclosed desiccator contents at a temperature of21 ± 5°Cfor 24 h. At the end ofthis period, remove the test sampleand weigh accurately. Calculate the moisture contentof the sample from the following equation:

M = WI -W2 x]OOWJ-W

where

M moisture content, in percent,

W mass of empty, clean and dry aluminiumdish,

WI mass of aluminium dish holding powderbefore drying, and

W2

:.= mass of dish holding powder after dryingthe powder.

4.9 Heat Resistance Test

4.9.1 The dry powder sample weighing 150 ± 2 g shallbe placed in a tinned steel cup having 75 mm diameterand 50 rnrn depth provided with a closely fitting flangedcover/lid. The lidded cup holding the powder shall thenbe placed in a thermostatically controlled oven maintainedat a temperature of60 ± 2°C for a week. The sample shallthen be cooled and examined for a caking or lumpsformation. The lumps or cakes, when dropped from aheight of 100 nun on a smooth glass surface or someother hard surface, shall be friable to pass the requirementof particle size distribution laid down in 4.4.

NOTE- Meeting of this requirement ensures that the drypowder is thermally stable and shall not decompose in normalambient extreme temperature. Also it ensure that non of itscorrst ituents including additives shall melt at an elevatedtemperature of 6()OC ir it is not so the powder shall be renderednon-effective extinguishing agent when used in cxtinguisherts)kept in locations having higher temperature such as boiler rooms,and near pipes carrying hot chemicals, steam, etc, in industries.

4.10 Free Flowing Characteristics (EfficientFluidit)')

4.10, I A dry chemical powder having howsoever goodfire inhibitory property when used in extinguishers maybe rendered ineffective it is does not flow in pipessatisfactorily.

Dry chemical powder are generally filled inextinguisher bodies whether portable or wheeled unitsor in fixed installations or in special dry chemicalpowder tenders. Moisture free compressed gases likenitrogen, carbon dioxide or air arc used to drive outthe powder. In doing so the powder is required to flowthrough metal pipes, bends, rubber flexible hoses, etc.If the powder has less mobility it can not be driven outsatisfactorily hence can not be projected on fire.

In the design of good extinguishers an effort is madeto loosen or aerate the powder before its finding wayinto the discharge pipes and fittings, etc so that a non­pulsating jet of powder is obtained.

4.10.2 Equipment

The device consists of two numbers of Erlenmeyerglass conical flasks each of I 000 011 capacity. Oneflask is inverted over the other such that they meetmouth to mouth. A clean, dry flask holding a knownmass of powder 500 g under test is kept horizontally.A rubber collar tube is put on its neck. A disc madeout of J mm thick stainless steel sheet and having aconcentric aperture of 26 mm diameter is fixedhorizontally into the neck. A similar clean, dry

5

IS 4308 : 2003

Erlenmeyer flask is inverted over the horizontal oneand the free end of the rubber made collar tube isslipped over so that it covers the neck. The purpose ofrubber tube made collar is to hold the two tlasks mouthto mouth meeting. A suitable apparatus is shown inFig. 4.

4.10.3 Procedure

This assembly is held vertically by their necks in asuitable stand. The assembly of the two flasks is thenturned rotated by 180 0 and kept held in this position,till all the powder mover/flows down to the lowerflask. In this process some aeration of the powdersample takes place. As soon as the entire quantity ofpowder falls into the lower flask, the assembly isimmediately again turned 180 0 and held in thisposition. In this way the process of aeration iscontinued and repeated so that in all aeration is doneonly ten times. Note that this aeration is to be done inquick succession without stopping in betweenconsecutive aeration.

Immediately after the tenth run is over the measurementof fluidity is commenced by recording the period in srequired for the powder to flow through completely.In quick succession total ten rneasurements are carriedout. The arithmetic mean time' t' of these timings iscalculated. Then the rate of flow that is, fluidity ofpowder is calculated by dividing the quantity 500 g bymean time '1' second. The sample of the powder isdeemed to have passed the requirement of fluidity ifthe rate of flow is not below 50 g/s.

4.11 Foam Compatibility

4.11.1 Equipment

The equipment shall consist of the following:

a) A foam making branch pipe having waterdischarge capacity of 7.5 l/min at 7 kgf/crn?pressure connected to a pressure vesselthrough a flexible rubber hose on one side.The pressure vessel is to be pressurized withthe help of an air compressor as shown inFig. 3 of IS 4989 (Part I).

b) A fire tray measuring internally 60 em x

25 cm x 20 cm deep made out of 3 mm thickmild steel sheet, with all welded, leak proofconstruction. The tray shall be kept on a standand shall have a sparged pipe ofstainless steelfitted on one side as shown in Fig. 5. Thesparged pipe shall have a spigot made on thefree end so that the LPG rubber tubing maybe easiJy and securely connected to it.

c) A domestic LPG gas cylinder fitted withregulator and rubber tube.

d) A suitable torch to set petrol, LPG on fire.

IS 4308 : 2003

ERLENMEYERFLASKS ----I...

1000 CC

RUBBERCOLLAR -----

.p20

_-tli,~~

APERTURE

LEVELLINGSCREW

004--------- 1- 250 --------~..

All dimensions in millimetres.

FIG. 4 ARRANGEMENT OF EQUIPMENT FOR FREE FLOWING

265 325

4.1 1.2 Procedure

The following procedure shall be followed:

a) Keep the fire tray measuring internally 60 emlength. 25 em breadth and 20 em height on a68 em high stand as shown in Fig. 5. The trayshould be clean and ensure that none of theholes made in the sparge pipe are clogged.

b) Pour 8 I of clean potable water into the trayso that the sparge pipe gets submerged.

6

c) Keep foam generating arrangement ready. Thepressure vessel is to be charged with apremixed solution ofprotein foam concentrateconforming to IS 4989 (Part I) at 4 percentconcentration (v/v) in clean potable water.

d) Pour 3 1ofn -haptane into the fire tray holdingwater layer.

e) Ignite the fuel and let it bum freely for lOs.

1) Using a suitable goose neck fitted on the foammaking branch pipe apply foam into the tray

IS 4308 : 2003

TRAY10 6·35 GAS PIPEWITH SEVEN HOLESOF ¢2'O (;}f::,

/~

680

ANGLE IRON

-M S STRIP

All dirncnsious ill millimctrcx.

F\(I. S T R;\ Y \\ I I If S T A\,' J)

on fire for lOs.

g) Start a stop watch.

h) Meanwhile, immediately connect the domesticLP(J gas line to the free end of the sparge pipe.

.i) Thirty second after the completion of foamapplication, open the gas line and ignite theI.PG bubbling out of thc fuam blanket homthe sparge pipe. ]mrncdiately start notingdown the time period required for completearea of tray to be involved into names. Letthis time be called T

1second.

NOTE Throughout the test LN. gas supply is 10 be

maintained at full throttle.

k ) Extinguish the tire. Let the tray cool down.

m) Report the procedure as given above from (a)to (e).

n) Put 60 g of the dry chemical powder sampleunder lest above the platform of the butterflyvalve of the puffer chamber. By operating thepuffer chamber at 276 k Nzrn? (40 psi), applythe powder on the burning tray. This makesthe fuel surface hot and powder particlesremain on exposed surface of fuel. The firemayor may not go out.

7

p ) lmrncdi.uc ly apply foam for lOs as donepreviously in (c) to (f).

q) Now repeat (g) to (j).

r) Record the time taken for involvement ofcomplete area of tray into flames. Let this timebe T~ second. A dry powder sample shall hedeemed compatible with the foam samplewith which it is tested if 1'2 is not less thanone half of r,

N011 --- For application 01 foum into tray the operator shouldwear tire protective hand gloves and face slucld and usc asuitable goose neck on the foam making nczzlv

4.12 Fire Knocking Down Properties

4.12.1 Procedure for Class B Fire

4.12.1.1 Equipment

The equipment shall consist of the following:

a) An air compressor,

b) An air pressure regulator and moisture trap(to eliminate moisture from compressed air)suitably mounted on a stand.

c) Weighing scales, weights and a plastic orstainless steel spoon.

IS 4308 : 2003

d) A stop watch,

c) A small torch and match box,

f) Stainless steel tire pan, as shown in Fig. 7,

g) Stainless steel tire pan cover. made ofasbestossheet.

h) A puffer chamber made out of stainless steelsheet mounted on a stand, as shown in Fig. 8,and

j) A graduated glass measuring cylinder ofI I capacity.

4.1 2.1.2 Fuel

600 1111 of normal heptane.

4.12.1.3 Procedure

a) Arrange the equipment as shown in the 011 aI m high table provided with a non­combustible top, kept ina draught free roomor enclosure fitted with exhaust fan(s) to ventout smoke when the test is over.

h) Conned the puffer chamber to compressedair reservoir using a high pressure rubber hoseline through an air pressure reducer-cum­regulator and a moisture trap.

c) With the puffer chamber valve shut, regulatethe pressure ofcompressed air till the pressureof the rnoisture free compressed air is set at276 kNzm'.

d) Fill the outer area of the scmielleptical shapedfire pan up to 2 mm below the edges with cleanpotable water.

e) Next, pour 5 I of water into the inner area ofthe fire pan.

t) Weight 30 ± I g of the sample powder. Weighfive numbers of such samples.

g) Remove the cap kept on the cylindricalstainless steel pipe embodying the butterflyvalve. Pour this mass of powder into the pipeprovided so as to place the powder on to theplatform of the spring loaded butterfly valvein closed position of the puffer chamber.Replace the cap.

h) Gently pour 600 rnl of n-heptane as fuel overwater container in the inner area of the firepan taking care that no fuel is splashed intothe outer area. The level of water is to beadjusted in the inner area such that top layerof the fuel is about 2 mm below the frontedge. Due care is to be exercised whilepouring fuel to avoid splashing of the fuelinto the outer area to avoid conditionsresulting in inconsistent fires or tires in theouter area and consequently inconsistentresults.

j) Ignite the fuel and simultaneously start thestop watch and let the fuel burn freely forlOs. As soon as lOs are over, simultaneouslyfully turn the butterfly valve in anti-clockwisedirection so as to open the valve. Also operatethe pet cock/stop cock provided on thecompressed air line so as to let compressedair line open and sample powder falling onthe puffer chamber inner plate get introducedinstantly into the air stream which is deliveredon the fire in the form of a dry powder cloudor dry powder puff over the flames whichsweeps out the burning flames to causeextinction offire. Conduct the test five timesout of which the sample powder mustextinguish the fire four times. If extinction isachieved in the first four tests the fifth oneneed not be carried out.

~75 R EGULAT INGVALVE

I06·UO·,AIR SUPPLY TUBE

BRAZED ORWELOEO FLUSH

PUFFER CHAMBERREST STANO

PRESSUREGAUGE

BASE MADE OF

:~Yi1~O~~~trD WITH

NOTE Typical arrangement has been given and single or double pan may be used as jacket optional.

All dimensions in millimetrcs.

FIRE PAN

PUFFERCHAM8ER

FIG. 6 GENERAL ARRANGEMENT OF EQUIPMENT FOR FIRE TEST

8

IS 4308 : 2003

~I330·0----------..._t

254.0~

ELEVATION SIDE VIE W

All dirucnsions ill millunetrcs.

FI(i. 7 FIRI' PAl\< (STAIM.I·S'-; Sn.I·L SIIFFT 2.24 n1(11)

CAP

l25·5 -

Tt

101-5

___~-l---176.0 ~

CYLINDERDIRECTION OFVALVE ROTATION

¢6·4-tQ·,DRILLED HOLE

(ORIFICE)

I127·0

T~-+101-6

~~_t

63-5

NOTE Permissible deviation + 0.5.

All dimensions in mrllrmctres.

FIG. 8 PUFH·.R CIfAMIH·.R (STAINU'SS STI·.FL SHEFT 1.6 mill)

IS 4308 : 2003

NOTES

I This test must be done in a room or enclosure where the winddoes not disturb the fire.

2 A suitable Halon 1211 extinguisher or COz extinguisher ordry chemical powder extinguisher or AFFF stored pressuremechanical foam extinguisher must be kept in attendance to1111.:cl any fire out-break exigency arising due to non-extinctionof tire or other reasons.

3 To obtain repeatable results the fire pan must be allowed to(opl down before repeating the test.

4.12.1.4 Precautions

Following precautions shall be taken during the test:

a) The distance between the lower edge of theoutlet of puffer chamber and the nearest edgeof the tire pan is of critical importance andshould therefore be maintained as shown inFig. 8.

b) The angle at which puffer chamber rests onthe stand is also of critical importance.

4.12.2 Procedure for Class C Fire

4.12.2.1 Any powder meeting the requirements ofClass B tire tests as described in 4.12.1, in addition bedeemed to possess the potential for achieving anadequate performance on Class C fires that is, firesinvolving gases.

4.13 Colour

The powder shall be of white colour.

5 GUIDANCE NOTES

a) All extinguishing powder must be safe for useon live electrical equipment, and must notcontain any electrically conductive material.

b) The various materials and additives used toproduce extinguishing powders should benon-toxic to humans.

c) The discharge of large amounts of drychemical powder may create hazards topersonnel in the vicinity such as reducedvisibility and temporary breathing difficulty.

d) Arnmon iurn phosphate and potassiumchloride are slightly acidic, and in thepresence ofmoisture, they can corrode metalssuch as steel, cast iron and aluminium.

e) Potassium bicarbonate, sodium bicarbonateand urea based potassium bicarbonate areslightly basic and in the presence or moisturethey can corrode metal such as aluminium,bronze and titanium.

t) However, prompt clean up, ifdone, can avoidsuch corrosion, ammonium phosphate based

10

agent will require same scraping and washingif exposed surfaces were hot when the agentwas applied.

g) Dry chemical powder shall not be consideredsatisfactory for use on machinery such ascarding equipment in textile operations anddelicate electrical equipment, because uponexposure to temperature in excess of 121°C,or relative humidity in excess of 50 percentdeposits will be formed which may becorrosive, conductive of electricity anddifficult to remove.

6 SAMPLING AND CRITERIA FORCONf"ORMITY

The details of the sampling and criteria for conformityare given in Annex B.

7 PACKING

7.1 The powder shall be packed in hermetically sealedmoisture proof plastic bags or containers lined withplastic in the quantities I, 2, 5, 10, 25 and 50 kg.

7.1.1 The strength of the container used shall be suchthat no distortion or failure of the container shall occurwhen it is kept on a flat surface on any of its sides/ends and a weight of 10 kg is applied to it. Thecontainer shall not disintegrate to any extent whendropped from a height of I m on a concrete surfaceafter being packed.

7.2 The powder of quantity 50 kg shall be packed inHM HOP bag conforming to is 7406 (Part 2).

8 MARKING

8.1 Each pack containing dry chemical powder shallbe labelled with the following information:

a) Manufacturer's narne or trade-mark;

b) Quantity of the powder, in kg;

c) Type: Ordinary or foam compatible;

d) Date of manufacture/Batch No.: and

e) Percentage of base material.

8.1.1 The packing may also be marked with theStandard Mark.

8.1.1.1 The use of the Standard Mark is governedby the provisions of the Bureau of Indian StandardsAct, 1986 and the Rules and Regulations madethereunder. The details of conditions under whichlicence for the use ofthe Standard Mark may be grantedto manufacturers or producers may be obtained fromthe Bureau of Indian Standards.

IS 4308 : 2003

ANNEXA

(C-'/ause2)

LIST OF REFERRED INDIAN STANDARDS

IS No.1607 : 1977

4905 : 196849X9

(Part ) : 19H5

TitleMethods for test sieving (firstrevision)Methods for random samplingFoam concentrate (compound) forproducing mechanical fuam for firefighting:Protein foam (second revision)

IS'N().(Part 2) : 19X4(Part 3) : 1987

7406 (Part 2) :)<JX6

TitleAqueous film forming foamFluoro protein foamJute bags for packing fertilizers:Part 2 Laminated bags manufac­tured from 380 g/srn ': 68 x 39tarpaulin fabric (first revision)

ANNEX B

(Clause 6)

SAl\lPLING PROCEDURE F()R DRY CHEMICAL POWDER FORFIGHTING CLASS 8 AND C FIRES

8-1 SCALF: ()F SAMPLING

B-1.1 Lot

All the containers in a single cousignment of thematerial of the same type drawn from a single batchof manufacture, shall constitute a lot.

B-2 NUI\1BER OF TESTS AND CRITERIA .'ORCONFORI\lITY

B-2. t Draw with an appropriate sampling instrument

8- J.2.1 These containers shall be selected from thelot at random. In order to ensure the randomness ufselection, procedures given in JS 4905 may befollowed.

B-2.3 The fire test and foam compatibility test(applicable only to foam compatibility type) shall alsobe carried out on the composite sample. Threesamples shall be tested for Class B fire. The lot shallbe considered as conforming to the requirements oftire test ifat least two samples completely extinguishthe fire. For foam compatibility, two samples shallbe tested. The lot shall be considered as conformingto the requirements of this test if both the samplespass.

a small portion of the material from different partsof each selected container. Thoroughly mix allportions of the marer ia l drawn from the samecontainer. The total quantity of the material drawnfrom each container shall be sufficient to conductall the tests given in 4. The material from each ofthe container so selected, shall be subjected to thetests for apparent density, particle size distribution,water repellency and free flowing. The lot shall beconsidered as conforming to these requirements ifall the samples meet the requirements.

B-2.2 For the tests for hygroscopicity, caking and heat,a composite sample shall be made of taking small butequal quantity of material from each of the selectedcontainers and one test shall be carried out for eachrequirements. The lot shall be considered asconforming to these requirements if a sample passesin both the requirements.

Sample Siu(3)

J45

Lot Stze(2 )

Up to SO5/ to 100101 to 150151 to :WO

:W I and above

Table 2 Scale of Sampling(Clause 8-1.2)

SIl'io.

(I)

I)

(I)

III)

i\')

v )

B-1.2 The sample shall be tested from each lot forascertaining the conformity of the material to therequirements of the standard. The number ofcontainersto be selected from each lot shall depend upon the size01" the lot and shall be in accordance with col I and 2ofTablc 2.

11

IS 4308 : 2003

ANN'EX C

(Forewords

COl\lMITTEE COMPOSITION

Fire Fighting Sectional Committee, CED 22

Organization

Ministry of Home Affairs. New Dcllu

Airport Authority of India. New Delhi

Andhra Pradesh Fire Services, l lyderabad

Bhabha Atomic Research Centre, Mumbai

Horubay Fire Brigade, Mumbai

Central Building Research Institute. Roorkee

Central Industrial Security Force, New Delhi

l'cnlral Public Works Department. New Delhi

Centre for Environment and Explosive Safety, Delhi

Concord Arai Pvt Limited. Chennai

Cuntrollcrate of Quality Assurance (Fire), Pune

Defence Researc..h and Development Organizarion, Delhi

Directorate General of Supplies and I>isposals, Hyderabad

lngruccr-in-Chicf">, Branch, New Delhi

hrc and Safety Appliances Company. Kolkata

Home Department (fire Service), Chennai

Institution of Fire Engineers (Indra), New Delhi

Koovcrj i Devshi and Company <P) Limited. Mumbai

K.V. fire Chemicals. Navi Murnbai

Loss Prevention Association of India. Mumbai

Mather and Platt (India) Limited. New Delhi

MECON Limited. Ranchi

Ncwage Industries, Mumbai

Northern Railway. New Delhi

Oil and Natural Gas Commission, Dehra Dun

Oil Industry Safety Directorate. New Delhi

Heal Value Appliances Limited. New Delhi

Sa/ex fin: Services Limited. Mumbai

12

Representutivets)

SUM I OM PRAKA~H (Chairman)

SUIU D. K. SHAMI (Alternate)

SHRI L. C. GUPTA

SURI H. S. R"WAT (Alternate)

SURJ SWARANJrt 51·.N

Ciurr FIRI: OFfiCER

CtIlH F'Rl OHICER

SHRI G. S. SAWANT (Alternate)

OR T. P. SHARMA

DR A. K. GUPTA (Alternate)

Du-rn Y (NSf'ECI'OR GENLRAL (FIR\')

SURI S. L. NAliARKAR (Alternate)

CHIEF ENGINEER (E)

SHRI A. K. KAI'OOR

SURI H. S. KAl'ARWAN iAlternate)

SURI R. RAMAJ<JUSHNAN

COL G. P. KRIStiNAMUR1IIY

DIRI:CrOR (FIR' SAFETY)

DI'I'liTY DIRH'IOI{ (FuH- SAFFTY) (Alt<.'rl/<J/e)

SIIKI R. C. SIIAltMA

SHRI S\JR'Nl)J'H KlIMAR tAlternate;

SIIRI M. GANGARAJIJ

SHR' V. K. VI RMA (Alternate)

SHRI R. A. DlIl1lY

SIiRI AlAY SII"-NKAR (Alternale)

511RI S. N. Kwmu

DIRH'TOR

DEPUTY DIRl:CTOR (A lternute)

PKI'SIOENl

GENERAL SLCREI ARY (AI/anule)

StiRI p, H. Sf:fHNA

Sllkl N. T PA~JWANI (Alternute)

SHRI H. M. SAttAORA

MANAnlNG DIRFCTOR

Sllkl D. K. SARKAR (Allemate)

SHRI DF.EPAK A(jARWAl

SHRJ R. N. CUAUiRA

StlRI SUNIL DAS (Alternate)

SHRI B. J. SHAH

SURI A. M. SHAt" (Alternate)

SHRI I. M. MANSOORI

SHRI R. P. SAXENA

SHRI NLERAJ SHARMA (A/lerna/e)

JOtN'Y' DIRECTOR (PROCESS)

SURI ASHUTOSH MANOAL

SURI J'Tt:.NDRA SHAH

SHRt SANDII' SHAll (Alternate)

tContinucd OIl page 13)

IS 4308 : 2003

(Continued/rom page 12)

Organization

Stale Bank of India. Mumbai

State Fire Training Centre, Mumbai

Steel Authority of India, Bokaro

Steel Authority of India, Rourkela

Stcelage Industries Limited, New Delhi

Surex Production and Sales (P) Limited, Kolkata

Tariff Advisory Committee. Mumhai

Tariff Advisory Committee. Chennai

Vijay Fire Protection Systems Pvt Limited. Mumbai

West Bengal Fire Service, Kolkata

In personal capacity (3J/296J-A. Vennala High School Road.Venualu, Cochill)

In personal capacity (2W2.5. Rajendra Nagar, New Delhi)

RIS Directorate General

Representativets]

SHRJ J. S. GAHLA\JT

DR NAVINCtlANDRA JAIN

SURI A. RAUTELA

SHR! C. P. SINGH (Alterna/e)

SHRI B. N. DAS

SHRJ B, P. DAS (Altanute)

CHIEF EXECUTIVI:

SHR! V. KAMAI.I\NAIHA (Alternatev

SHRI TARIT SUR

SHRf D. NHKil (A/lerna/e)

SHRI A. MIJKHf-RJFF

SHRI H. C. MAHESH KI''1AR (Alternates

SIIRI T. R. A. KRISHNAN

SIIIlI HARtSH SALOT

SllRI B. PATIIAK

SHill G. H. Mf'oJON

SURI S, K. Dill 10

S'HO S. K. JAIN. Director & Head (CED)[Representing Director General (£l.-011;('/o)!

Member SecretarvSWH S. CIIATlJR\TDI

.'oint Director (CEO), HIS

13

Bureau of Indian Standards

HIS is a statutory institution established under the Bureau of Indian Standards Act. 1986 to promoteharmonious development of the activities of standardization, marking and quality certification of goodsand attending to connected matters in the country.

Copyright

HIS has the copyright of all its publications. No part of these publications may be reproduced in any formwithout the prior permission in writing of HIS. This does not preclude the free use, in the course ofimplcmcnting the standard, of necessary details, such as symbols and sizes, type or grade designations.Enquiries relating to copyright be addressed to the Director (Publications), 81S.

Review of I ndian Standards

Amendments arc issued to standards as the need arises on the basis of comments. Standards are also reviewedperiodically; a standard along with amendments is reaffirmed when such review indicates that no changes arcneeded; if the review indicates that changes are needed. it is taken up for revision. Users of Indian Standardsshould ascertain that they are in possession of the latest amendments or edition by referring to the latest issue of'HIS Catalogue' and ·Standards: Monthly Additions'.

This Indian Standard has been developed from Doc: No. CED 22 (5741).

Amendments Issued Since Publication

Amend No. Date of Issue Text Affected

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