Electrical Safety Clearance (Northern Ireland Electricity) (Part-3)

 

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 Meter

7.0 Meter

7.0 Meter

Line conductor to road surface

5.8 Meter

6.1 Meter

6.4 Meter

6.4 Meter

7.4 Meter

8.1 Meter

Line conductor to road surface of high load routes

6.9 Meter

6.9 Meter

6.9 Meter

7.2 Meter

8.5 Meter

9.2 Meter

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

4.6 Meter

4.6 Meter

4.6 Meter

–

–

–

Clearances of Electrical Line to Other Objects:

Description of Clearance

<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 Meter

3.0 Meter3.4 Meter4.6 Meter5.3 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 Meter

0.8 Meter1.2 Meter2.4 Meter3.1 Meter
Line conductors to irrigates, slurry guns and high-pressure hoses

30 Meter

30 Meter30 Meter30 Meter30 Meter
Line conductors to playing fields

8.5 Meter

8.5 Meter8.5 Meter8.5 Meter8.5 Meter
Line conductors to Caravan Sites

9.0 Meter

9.0 Meter9.0 Meter9.0 Meter9.0 Meter
Horizontal clearances to wells

15.0 Meter

15.0 Meter15.0 Meter15.0 Meter15.0 Meter

Clearances of Electrical Line to Trees and Hedges:

Description of Clearance

<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 Meter

0.8 Meter1.2 Meter2.4 Meter3.1 Meter
Line conductor or bare live metalwork to trees or hedges capable of supporting a ladder or being climbed.

3.0 Meter

3.0 Meter3.4 Meter4.6 Meter5.3 Meter
Line conductor or bare live metalwork to trees falling towards the overhead line with the line conductors hanging vertically.

0.8 Meter

0.8 Meter1.2 Meter2.4 Meter3.1 Meter
Line conductors to trees in Orchards

3.0 Meter

3.0 Meter3.4 Meter4.6 Meter5.3 Meter

 Clearances of Electrical Line to Street Lighting:

Description of Clearance

0.4 KV

11 KV

33KV

110KV

220 KV

400KV

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 column0.3 Meter

–

–

–

–

–

Insulated line conductor to lantern1.0 Meter

–

–

–

–

–

Column to nearest LV pole1.5 Meter

–

–

–

–

–

Line conductor to street lighting column with

 

 

 

 

 

 

(i) Column in normal upright position.–1.7 Meter1.7 Meter2.3 Meter3.3 Meter4.0 Meter
(ii) Column falling towards line with line conductor hanging vertically only–1.7 Meter1.7 Meter2.3 Meter3.3 Meter4.0 Meter
(iii)Column falling towards line–0.4 Meter0.4 Meter0.8 Meter1.4 Meter1.9 Meter

 Clearances of Electrical Line to Waterways:

Description of Clearance

0.4 KV

11 KV

33KV

110KV

220 KV

400KV

Navigable Waters: Lower bank to conductor or earth wire

10.5 Meter

10.5 Meter10.5 Meter10.5 Meter10.5 Meter10.5 Meter
Minor Watercourses : Lower bank to conductor or earth wire

7.6 Meter

7.6 Meter7.6 Meter7.6 Meter7.6 Meter7.6 Meter

 Clearances to Railways:

Description of Clearance

0.4 KV

11 KV

33KV

110KV

220 KV

400KV

Line conductor to ground level

6.1 Meter

6.1 Meter6.1 Meter

6.7 Meter

7.0 Meter

7.6 Meter

Line conductor to ground level on or across vehicle parks7.6 Meter8.5 Meter8.5 Meter9.1 Meter9.4 Meter10.1 Meter
Line conductor to ground level at roads and yards, where road mobile cranes are likely to be employed10.7 Meter

10.7 Meter

10.7 Meter

11.2 Meter

11.5 Meter

12.2 Meter

Line conductor to Rail level7.3 Meter7.3 Meter7.3 Meter8.0 Meter8.2 Meter8.8 Meter
Line conductor to the level of buildings, gantries or other structures (including those carrying traction wires) on which a man may be3.0 Meter3.0 Meter3.0 Meter3.7 Meter4.6 Meter6.1 Meter
Line conductor to poles and other projections.2.4 Meter2.7 Meter2.7 Meter3.0 Meter3.7 Meter5.5 Meter
Line conductor to any other wire other than traction wires.1.8 Meter1.8 Meter1.8 Meter2.4 Meter3.0 Meter3.7 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 Meter

15 Meter

15 Meter

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 Meter

4.6 Meter

5.3 Meter

(2) 2274 to 9092 litre capacity

7.6 Meter

7.6 Meter

7.6 Meter

7.6 Meter

7.6 Meter

7.6 Meter

(3) More than 9093 litre.

15 Meter

15  Meter

15  Meter

15  Meter

15 Meter

15  Meter

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 Meter

3.7 Meter

4.4 Meter

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 Meter

3.7 Meter

4.4 Meter

Lowest line conductor or earth wire of upper line to any point on a support of the lower line on which a person may stand.

2.7 Meter

2.8 Meter

3.0 Meter

3.4 Meter

4.6 Meter

5.3 Meter

Support of upper line and any conductor of lower line.

7.5 Meter

7.5 Meter

7.5 Meter

15 Meter

15 Meter

15 Meter

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

Description of Clearance

<33 KV

110KV

220KV

400 KV

Passing clearance: fixed height loads

0.8 Meter1.4 Meter2.4 Meter3.1 Meter

Passing Clearance: variable height loads.

2.3 Meter3.2 Meter4.1 Meter5.0 Meter

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

Description of Clearance

<33 KV

110KV

220KV

400 KV

Minimum horizontal distances to safety barriers

6.0 Meter

9.0 Meter12.0 Meter14.0 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

33 KV to 66 KV

1.8 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

22 KV & LV Line

0.75 Meter

33 KV & LV Line

0.90 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) LineMin 1.2 Meter
Telecommunication Line (Covered) to LV (Bare) LineMin 0.6 Meter
Telecommunication Line (Bare) to Stay (Bare) WireMin 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 Conductor0.8 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