Electrical Safety Clearance

Electrical Safety Clearance (Part-1)AUGUST 8, 2012 9 COMMENTS

Standard: Qatar General Electricity & Water Corporation

Minimum Safety Clearance of Pipelines from Electrical Tower:

DescriptionVoltage

33KV/66KV/132KV 220KV/400KV

The right of way (ROW) (widths on either side of the center line of overhead transmission lines )

25 Meter 50 Meter

Other than the roadways and boundary fences of security establishments any temporary or permanent structures / buildings, parapet walls,

Not within 25 Meter Not within 50 Meter

With All Underground services crossing the way leave (from the nearest tower foundation)

35 Meter (Min) 50 Meter (Min)

The nearest side of the road reservation to the nearest tower foundation

25 Meter35 Meter,50

Meter

The pipelines (water, oil/gas etc.) crossing (respectively away from the nearest base of tower leg). Pipe-lines shall not be laid parallel to the overhead line within the limits of a way leave (ROW).

25 Meter (Min)35

Meter(Min) ,50 Meter(Min)

Cables crossing the transmission lines way leave

25 Meter 35 Meter,50 Meter

(ROW) respectively away from the nearest base of tower leg.

Foundations and civil structures (Temporary or permanent) will not be permitted in the close proximity to the cable circuit. A minimum horizontal distance from such structures to the nearest edge of the cable trench shall be observed

Min 1.5 Meter Min 1.5 Meter

Clearance among Electrical Line-Telephone- Water-Sewerage -Gas Line

Service Vertical Clearance(Min)

Water Line (to cross below EHV cable level)

0.5 Meter

Sewerage Mains (to cross below EHV cable level)

1.0 Meter

Drainage Mains (to cross below EHV cable level)

0.5 Meter

Gas pipes 0.6 Meter

Telephone lines 0.5 Meter

LV / 11kV cables 0.5 Meter

Safety Clearance for Excavation of Land :

Type of Excavation Distance

Use of heavy mechanical excavators (other than hand operated pneumatic jack hammers) or driving sheet piles

Not less than 3 Meter from the edge of cable, cover, cable joint

Heavy machinery engaged in the civil construction or road works

operating load/thrust/ weight will not be applied directly on the cable installation

Trench excavations parallel to the cable installations

Minimum separation of 1 Meter to the nearest edge of cable tile

Laying of metal pipes over a long distance parallel to cable

Not permitted unless the Step and Touch Potentials at any point of the pipe line do not exceed 65 Volts.

(A) Inside Towns

Distance between Tower’s foundation to Pipeline in parallel and intersections.

Voltage Min Distance

380/220V 0.5 Meter

20KV 2 Meter

63KV 7 Meter

132KV 10 Meter

230KV and Above 20 Meter

Distance between underground power cables to wall of gas pipelines in parallel routes.

Voltage Min Horizontal Distance

Min Vertical Distance

380/220V 1 Meter 0.5 Meter

20KV 2 Meter 1 Meter

63KV 3 Meter 1.5 Meter

(B) Outside of Towns:

Distance between Tower’s foundation to Pipeline in parallel and intersections.

KVMin Distance in

Parallel Route (Up to 5 Km)

Min Distance in Parallel Route (Above 5 Km)






Distance between overhead lines to gas pipelines at intersections.

KV Min Distance

20KV 8 Meter

63KV 9 Meter

132KV 10 Meter

230KV 11 Meter

400KV 12 Meter

Distance between Tower’s foundations to gas pipelines at intersections.

KV Min Distance

20KV 20 Meter

63KV and Higher 30 Meter

Right Of Way (R.O.W) From Roads:

Highway Distance

High Way : (38 meter from one side of Central Line of Highway)

76 Meter

First Class State Road=(22.5 meter from one side of Central Line of Highway)

45 Meter

Second Class State Road=(17.5 meter from one side of Central Line of Highway)

35 Meter

Third Class State Road =(12.5 meter from one side of Central Line of Highway)

25 Meter

Forth Class State Road=(7.5 meter from one side of Central Line of Highway)

15 Meter

General Electrical Safety Clearance:

KV Description Distance

Up to 11 KVAt points where the lines cross roads or

railwaysMin 6 Meter Height

Up to 11 KV parallel to roads the Min 5.5 Meter Height

Up to 11 KVlines cross totally

desert regions where no traffic is possible

Min 5.5 Meter Height

20 KV to 66 KV

All Location Min 6 Meter Height

Up to 11 KV Conductor JointNo joint shall be closer

than 3 meters to a point of support

33 KV & 66 KV

Conductor Joint No tension joints shall be used unless specially approved.


Code: Indian Electricity Rules/ Central Electricity Authority:

Right of Way Clearance (As per GETCO Standard):

KV Min ROW

66 KV 18 Meter

132 KV 27 Meter

220 KV 35 Meter

400KV 52 Meter (Single Circuit)

400 KV 48 Meter (Double Circuit)

Minimum clearances between Electrical Lines crossing each other:

Voltage 66 KV 132 KV 220 KV 400 KV

66 KV 2.4 Meter

3 Meter 4.5 Meter

5.4 Meter

132 KV 3 Meter 3 Meter 4.5 Meter

5.4 Meter

220 KV 4.5 Meter

4.5 Meter

4.5 Meter

5.4 Meter

400 KV 4.5 Meter

5.4 Meter

5.4 Meter

5.4 Meter

Permissible Min ground Clearance of Electrical Line:

KV Ground Clearance Over National Highway

66 KV 6.1 Meter 8.0 Meter



400KV 8.8 Meter 10.8 Meter

Clearance for Telephone line Crossings Power Line:

KV Clearance (Min)

66 KV 2.4 Meter

132 KV 2.7 Meter

220 KV 3.0 Meter

Vertical Clearance between Electrical Line and railway tracks.

KV Clearance (Min)

66 KV 14 Meter

132 KV 14.6 Meter

220 KV 15.4 Meter

400 KV 17.9 Meter

Clearance from Buildings to low, medium & high voltage lines:

Voltage Description Distance

Low & Medium Voltage

Flat roof, open balcony, verandah roof ,When the line passes above the building a vertical clearance from the

2.5 Meter

highest point


Line passes adjacent to the building a horizontal clearance from the nearest point

1.2 Meter


Line passes above the building a vertical clearance

2.5 Meter


Line passes adjacent the building a Horizontal clearance

1.2 Meter

11 KV to 33 KV

Line passes above or adjacent to any building or part of a building

3.7 Meter

Above 33 KV Line passes above or adjacent to any building or part of a building

3.7+(0.3 for every additional 33 KV )

Up to 11 KV The horizontal clearance between the nearer conductor and any part of such building

1.2 Meter

11 KV to 33 KV

The horizontal clearance between the nearer conductor and any part of such building

2.0 Meter

Above 33 KV The horizontal clearance between the nearer conductor and any part ofsuch building

2.0 + (0.3 for every additional 33 KV )

Clearance above ground at the lowest conductor:

Voltage Description Distance


Across a street 5.8 Meter

High Voltage Across a street 6.1 Meter


Along a street 5.5 Meter

High Voltage Along a street 5.8 Meter


Elsewhere than along or across any street

4.0 Meter

High Voltage Elsewhere than along or across any street

5.2 Meter

33 KV & EHV Clearance above ground(Add 0.3 Meter for every 33 KV Volts in 5.2 Meter)

Min 6.1 Meter

Vertical Clearance at Middle of Span:

Span Vertical Clearance (At Middle of Span)

200 Meter 4.0 Meter

300 Meter 5.5 Meter

400 Meter 7.0 Meter

500 Meter 8.5 Meter

Safety Clearance from Live Part in Outdoor Substation:

KV Safety Working Clearance

12 KV 2.6 Meter

36 KV 2.8 Meter

72.5 KV 3.1 Meter

145 KV 3.7 Meter

220 KV 4.3 Meter

400KV 6.4 Meter

800 KV 10.3 Meter

Lying of Telecommunication Cables with Power Cables (>33 kV).

Cable Min. Distance

Power cable of voltage exceeding 33 kV shall be laid

Min 1.2 Meter depth

Underground telecommunication cable shall be with underground power cable of voltage exceeding 33 kV.

Min 0.6 Meter Separate from Power Cable

Safe approach limits for people:

Voltage

214V to 415 KV

11KV

33KV

66KV

132KV

275KV

Person 1.3 2.0 3.0 4.0 5.0 6.0

using manually operated tool

Meter

Meter

Meter

Meter

Meter Meter

Person using power operated tool

3.0 Meter

3.0 Meter

3.0 Meter

4.0 Meter

5.0 Meter

6.0 Meter


Standard: Northern Ireland Electricity (NIE), 6/025 ENA

Clearances of Electrical Line to Ground and Roads:

Description of Clearance

0.4 KV

11 KV

33KV

110KV

220 KV

400KV

Line conductor to any point not over road

5.2 Meter

6.1 Meter

6.4 Meter

6.4 Mete

r

7.0 Meter

7.0 Mete

r

Line conductor to road surface

5.8 Meter

6.1 Meter

6.4 Meter

6.4 Mete

r

7.4 Meter

8.1 Mete

r

Line conductor to road surface of high load routes

6.9 Meter

6.9 Meter

6.9 Meter

7.2 Mete

r

8.5 Meter

9.2 Mete

r

Bare live metalwork ( transformer terminals, jumper connections, etc)

4.6 Meter

4.6 Meter

4.6 Meter

- - -

Clearances of Electrical Line to Other Objects:


<11 KV

33 KV

110KV

220KV

400 KV

Line conductor or bare live metalwork to any object that is normally accessible (including permanently mounted ladders and access platforms) or to any surface of a building

3.0 Mete

r

3.0 Meter

3.4 Meter

4.6 Meter

5.3 Meter

Line conductor or bare live metalwork to any object to which access is not required AND on which a person cannot stand or lean a ladder

0.8 Mete

r

0.8 Meter

1.2 Meter

2.4 Meter

3.1 Meter

Line conductors to irrigates, slurry guns and high-pressure hoses

30 Mete

r

30 Meter

30 Meter

30 Meter

30 Meter

Line conductors to playing fields

8.5 Mete

r

8.5 Meter

8.5 Meter

8.5 Meter

8.5 Meter

Line conductors to Caravan Sites

9.0 Mete

r

9.0 Meter

9.0 Meter

9.0 Meter

9.0 Meter

Horizontal clearances to wells

15.0 Mete

r

15.0 Meter

15.0 Meter

15.0 Meter

15.0 Meter

Clearances of Electrical Line to Trees and Hedges:


<11 KV

33 KV

110KV

220KV

400 KV

Line conductor or bare live metalwork to trees or hedges unable to support a ladder or being climbed.

0.8 Mete

r

0.8 Meter

1.2 Meter

2.4 Meter

3.1 Meter

Line conductor or bare live metalwork to trees or hedges capable of supporting a ladder or being climbed.

3.0 Mete

r

3.0 Meter

3.4 Meter

4.6 Meter

5.3 Meter

Line conductor or bare live metalwork to trees falling towards the overhead line with the line conductors hanging vertically.

0.8 Mete

r

0.8 Meter

1.2 Meter

2.4 Meter

3.1 Meter

Line conductors to trees in Orchards

3.0 Mete

r

3.0 Meter

3.4 Meter

4.6 Meter

5.3 Meter

Clearances of Electrical Line to Street Lighting:

Description of Clearanc

0.4 KV

11 KV

33KV

110KV

220 KV

400KV

e

Line conductor to Lantern on same pole

1.0 Meter

- - - - -

Bare line conductor to lantern or column below.

1.5 Meter

- - - - -

Insulated line conductor to column

0.3 Meter

- - - - -

Insulated line conductor to lantern

1.0 Meter

- - - - -

Column to nearest LV pole

1.5 Meter

- - - - -

Line conductor to street lighting column with

(i) Column in normal upright position.

- 1.7 Meter

1.7 Meter

2.3 Meter

3.3 Meter

4.0 Meter

(ii) Column falling towards line with line conductor hanging vertically only

- 1.7 Meter

1.7 Meter

2.3 Meter

3.3 Meter

4.0 Meter

(iii)Column falling towards line

- 0.4 Meter

0.4 Meter

0.8 Meter

1.4 Meter

1.9 Meter

Clearances of Electrical Line to Waterways:


0.4 KV

11 KV

33KV

110KV

220

KV

400KV

Navigable Waters:Lower bank to conductor or earth wire

10.5

Meter

10.5 Meter

10.5 Meter

10.5 Meter

10.5 Meter

10.5 Meter

Minor Watercourses :Lower bank to conductor or earth wire

7.6 Meter

7.6 Meter

7.6 Meter

7.6 Meter

7.6 Meter

7.6 Meter

Clearances to Railways:


0.4 KV

11 KV

33KV

110KV

220 KV

400KV

Line conductor to ground level

6.1 Meter

6.1 Meter

6.1 Meter

6.7 Mete

r

7.0 Meter

7.6 Mete

r

Line conductor to ground level on or across vehicle parks

7.6 Meter

8.5 Meter

8.5 Meter

9.1 Meter

9.4 Meter

10.1 Meter

Line conductor to ground level at roads and yards, where road mobile cranes are likely to be employed

10.7 Meter

10.7

Meter

10.7

Meter

11.2 Mete

r

11.5

Meter

12.2 Mete

r

Line conductor to Rail

7.3 Meter

7.3 Meter

7.3 Meter

8.0 Meter

8.2 Meter

8.8 Meter

level

Line conductor to the level of buildings, gantries or other structures (including those carrying traction wires) on which a man may be

3.0 Meter

3.0 Meter

3.0 Meter

3.7 Meter

4.6 Meter

6.1 Meter

Line conductor to poles and other projections.

2.4 Meter

2.7 Meter

2.7 Meter

3.0 Meter

3.7 Meter

5.5 Meter

Line conductor to any other wire other than traction wires.

1.8 Meter

1.8 Meter

1.8 Meter

2.4 Meter

3.0 Meter

3.7 Meter

Clearances of Electrical Line to Fuel Tanks:

Description of

Clearance

0.4 KV

11 KV

33KV

110KV

220

KV

400KV

Horizontal clearance from line conductors to petrol tanks and vents

15 Meter

15 Meter

15 Meter

15 Mete

r

15 Meter

15 Mete

r

Horizontal clearance from line conductors to liquid

gas tanks

(1) 459 to 2273 litre capacity

3.0 Meter

3.0 Meter

3.0 Meter

3.4 Mete

r

4.6 Meter

5.3 Mete

r

(2) 2274 to 9092 litre capacity

7.6 Meter

7.6 Meter

7.6 Meter

7.6 Mete

r

7.6 Meter

7.6 Mete

r

(3) More than 9093 litre.

15 Meter

15 Meter

15 Meter

15 Mete

r

15 Meter

15 Mete

r

Vertical clearance from line conductors to fuel oil tanks

Please refer Clearances to Objects

Clearances of Electrical Lines to other Electrical Lines:

Description of

Clearance

0.4 KV

11 KV

33KV

110KV

220 KV

400KV

Lowest line conductor or earth wire of upper line to highest line conductor of lower line.

1.0 Meter

1.8 Meter

2.0 Meter

2.5 Mete

r

3.7 Meter

4.4 Mete

r

Lowest line conductor or earth wire of upper line to earth wire of lower line where erected.

0.7 Meter

1.4 Meter

1.6 Meter

2.5 Mete

r

3.7 Meter

4.4 Mete

r

Lowest line conductor or earth wire of

2.7 Meter

2.8 Meter

3.0 Meter

3.4 Mete

r

4.6 Meter

5.3 Mete

r

upper line to any point on a support of the lower line on which a person may stand.

Support of upper line and any conductor of lower line.

7.5 Meter

7.5 Meter

7.5 Meter

15 Mete

r

15 Meter

15 Mete

r

Vertical Passing Clearance (sites where vehicles will pass below the lines):


<33 KV 110KV 220KV

400 KV

Passing clearance: fixed height loads

0.8 Meter

1.4 Meter

2.4 Meter

3.1 Meter

Passing Clearance: variable height loads.

2.3 Meter

3.2 Meter

4.1 Meter

5.0 Meter

Horizontal Clearance (sites where there will be no work or passage of plant under lines):


<33 KV 110KV 220KV

400 KV

Minimum horizontal distances to safety barriers

6.0 Meter

9.0 Meter

12.0 Meter

14.0 Meter

Distance between Conductors of Same/Different Circuit (On Same Support):

Higher Voltage of either Circuit

Lower Voltage of either Circuit

Distance between Circuits

< 33 KV < 1 KV 1.0 Meter

< 33 KV > 1 KV 1.2 Meter

33 KV to 110 KV < 1 KV 1.5Meter

33 KV to 110 KV > 1 KV 2.0 Meter

Above 110 KV All 2.5 Meter

Vertical Distance between Conductors of different Circuit (On Different Support):

Higher Voltage of either Circuit Distance between Circuits

< 1 KV 0.6 Meter

1 KV to 33 KV 1.2 Meter


110 KV 2.4 Meter

220 KV 2.8 Meter

Distance between Conductors (Taken down from Pole to other Support, on Transformer):

Voltage Distance between Circuits

11 KV & LV Line 0.60 Meter



Horizontal Distance of Telecommunication Line & Overhead Line:

Description of Clearance Distance

Telecommunication Line(Not insulated) to HV Line

Min 1.6 Meter

Telecommunication Line (Bare) to LV (Bare) Line

Min 1.2 Meter

Telecommunication Line (Covered) to LV (Bare) Line

Min 0.6 Meter

Telecommunication Line (Bare) to Stay (Bare) Wire

Min 0.3 Meter

Passage Way for Metal clad Switchgear:

Description of Clearance Distance

Clean &unobstructed Passages at the front of any Low/High Voltage Switchgear.

1.0 Meter wide & 2.5 Meter

high

Clean &unobstructed Passages at side or under any earthed enclosure containing Bare Conductor

0.8 Meter wide & 2.2 Meter high

Safe approach distance for Person from Exposed Live Parts:

Circuit Voltage Distance

< 1 KV 0.5 Meter

11 KV 1.5 Meter

22 KV 2.0 Meter

33 KV 2.5 Meter

66 KV 3.0 Meter

110 KV 4.0 Meter

>220 KV 6.0 Meter


Standard: ETSA Utilities

Vertical Clearances between Services:

Service LV Cable HV Cable

Common Pipe 0.100 Meter 0.100 Meter

Gas Pipe 0.200 Meter 0.200 Meter

Sewer Pipe 0.300 Meter 0.300 Meter

Water Pipe 0.600 Meter 0.600 Meter

Horizontal Clearances between Services:

Service LV Cable HV Cable

Common Pipe 0.100 Meter 0.100 Meter

Gas Pipe 0.200 Meter 0.200 Meter

Sewer Pipe 1.0 Meter 1.0 Meter

Water Pipe 0.600 Meter 0.600 Meter

Standard: UK Power Networks – EI 02-0019

Cable Installation Depths:

Voltage Area Depth (min)

Low Voltage

Footways, grass verges or private property

0.450 Meter

Carriageways (including road crossings)

0.600 Meter

Normal agricultural land (not deep ploughing)

1.0 Meter

Agricultural land subject to deep ploughing

1.2 Meter

11 KV to 20 KV


0.600 Meter


0.750 Meter


1.0 Meter


1.2 Meter

33 KV to 132 KV


0.900 Meter


0.900 Meter


1.0 Meter


1.2 Meter

Auxiliary Multi-core & Multi-pair

Cables


0.450 Meter


0.600 Meter


1.0 Meter


1.2 Meter

On Cable Ladder for LV to HV

The Horizontal clearance between cables on cable ladders

2X Dia of Cable of Largest Cable or min 150

mm

The clearance from a supporting wall 20 mm

The vertical clearance between cables is greater

150 mm

If the number of cables > 4, they are to be installed in a horizontal

Minimum Approach Distance of Crane or Moving Part from Live Conductor:

Voltage

Without Safety ObservationFor

ordinary Person

Un insulated portions

Insulated portions

Upto1KV 2 Meter 1.0 Meter 3.0 Meter

11 KV 2 Meter 1.4 Meter 3.0 Meter

22 KV 2.4 Meter 2 Meter 3.0 Meter



132 KV 3.0 Meter 3.0 Meter 3.0 Meter




Minimum Fixed Clearances for Electrical Apparatus (Isolation Points):

Voltage Fixed Clearance

Up to 11Kv 0.320 Meter

11KV to 33KV 0.320 Meter




Standard: New Zealand Electrical Code:

Min Safe Distance between Buildings and Overhead Line:

Voltage Pole Tower

11 kV to 33 kV 2 Meter 2 Meter

33 kV to 66 kV 6 Meter 6 Meter

66 kV and Above 8 Meter 8 Meter

Min Safe Distance for excavation near Overhead Line:

Description of ClearanceFrom Pole (Min)

From Tower (min)

Excavation in land more than 750mm depth

8 Meter 12 Meter

Excavation in land up to750mm depth

2.2 to 5 Meter

6 to12 Meter

Excavation in land up to300mm depth

2.2 Meter 6 Meter

Construction near 11KV to 33KV Line 2.2 Meter 6 Meter

Construction near 33KV to 66KV Line 6 Meter 9 Meter

Construction near 66KV and more 8 Meter 12 Meter

Wire Fence near 1KV to 66KV Line 2.2 Meter 2.2 Meter

Wire Fence near 66KV and more 5 Meter 5 Meter

Min Safe Distance for Tower Carin near Electrical Tower:

Description of Clearance Distance (Min)

Mobile Carin movement 4.0 Meter

Tower Carin movement 4.0 Meter

Carin movement 4.0 Meter

Moving Activity above height of Tower 4.0 Meter

Hedge Cutter movement 4.0 Meter

Min Safe Vertical Distance above Railway Track:

Description of Clearance Distance (Min)

Earthed conductors 5.5 Meter

Stay wires 5.5 Meter

Conductors up to 33 kV 6.5 Meter

Conductors above 33 kV to 220 kV 7.5 Meter

Conductors above 220 kV. 8 Meter

Min Distance between two Conductors on Same Supports:

High Voltage Circuit

High Voltage Circuit

Distance between circuits(min)

Up to 33 KV Up to 1KV 1.0 Meter

Up to 33 KV More than 1KV 1.2 Meter

33 KV to 110 KV Up to 1KV 1.5 Meter

33 KV to 110 KV More than 1KV 2.0 Meter

More than 110 KV All 2.5 Meter

Min Distance between two Conductors on Different Supports:

High Voltage Circuit Distance (min)

Up to 1 KV 0.6 Meter



110 KV 2.4 Meter

More than 220 KV 2.8 Meter

Min Safety Distance from Electrical Apparatuses:

Description of Clearance Distance (min)

Passage In front of Metal Clad Switchgear (UP to HV)

1.0 Meter wide 2.5 Height

Passage In rear or side of Metal Clad 1.0 Meter wide 2.2

Switchgear (UP to HV) Height

Passage at any side of Metal Clad Switch gear containing Bare conductor (UP to HV)

0.8 Meter wide 2.2 Height

Min Approach Distance for Non-Competent Person near exposed Live Parts:

Voltage Distance (min)

Below 110 kV 4.0 Meter

220 kV and above 6.0 Meter

Min Approach Distance for Competent Person near exposed Live Parts:


Below 1 kV 0.5 Meter

11 kV 1.5 Meter

22 kV 2.0 Meter

33 kV 2.5 Meter

66 kV 3.0 Meter

110 kV 4.0 Meter

220 kV and above 6.0 Meter

Electrical Safety Clearance (Part-6)AUGUST 22, 2012 1 COMMENT

Standard: Western Power Company.

Water Safely Clearance on Electrical Fires:

Voltage Minimum distances between a nozzle producing a fog stream of fresh

water and a live conductor

Up to 750 V 1.5 Meter

750 V to 15 KV 4.0 Meter


Minimum Approach Distance for Authorized Person:

This is the minimum distance that must be maintained by a person, vehicle or mobile plant.



1 V to 6.6 KV 0.7 Meter

6.6 KV to 11 KV 0.7 Meter







Minimum Approach Distance for Ordinary Person:



1 V to 6.6 KV 3.0 Meter

6.6 KV to 11 KV 3.0 Meter







Minimum Approach Distance for Vehicle & Plant for Ordinary Person:

VoltageDistance (min)

Mobile Plant Vehicle

Up to 1 KV 3.0 Meter 0.6 Meter

1 V to 6.6 KV 3.0 Meter 0.9Meter

6.6 KV to 11 KV 3.0 Meter 0.9Meter

11 KV to 22 KV 3.0 Meter 0.9Meter

22 KV to 33 KV 3.0 Meter 0.9Meter

33 KV to 66 KV 3.0 Meter 2.1 Meter




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Electrical Safety Clearance