Incidents involving electricity PN796

Question 1

the minimum safe approaching distance when using monitors (ground or aerial) is?

Answer 1

30m corridor

Question 2

once Wind Turbine power isolation has been requested and blades “locked off”, does that remove residual electrical charge?

Answer 2

no - locking blades does not remove elec. risk

Question 3

ICs must consider the effect of isolating power supplies in which three types of premises?

Answer 3

a) where there are machine processes
b) the absence of electrical supplies will affect occupants safety or welfare
c) there may be an adverse impact on business continuity

Question 4

Rescues - When carrying out a rescue in the vicinity of overhead lines, substations and other electrical equipment belonging to the electricity supply industry what is the minimum safe approach distance?

Answer 4

5m

Question 5

when can electrical gloves be used?

Answer 5

when voltage is known to be less than 3300v

Question 6

what is the initial cordon for a turbine incident

Answer 6

300m

Question 7

Ground and aerial appliances should not be used within how many meters from a live conductor?

Answer 7

30m

Question 8

Electrical hazards in a fire situation

4 listed

Answer 8

Large quantities of fuel may be stored (within power stations)

Oil filled transformers

Insulating materials

Gearbox oil

Question 9

If it is confirmed the residual electrical supply is of low voltage can action be taken?

Answer 9

Yes providing appropriate controls are put in place e.g electrical gloves

Question 10

the minimum safe approaching distance in dense smoke or flames for approaching the conductor is?

Answer 10

20 corridor

Question 11

what is the usual cordon recommended as a starting point for wind turbine fires?

Answer 11

300m

Question 12

what two things will an electrical premises (or equipment concerned with generation & supply of electricity) have to restrict access?

Answer 12

1. secure doors to switch rooms etc

2. fencing around installations

Question 13

minimum safe distance when using ground monitor on overhead cables

Answer 13

30m

Question 14

which firefighting media does not damage electrical equipment?

Answer 14

CO2

vapourising liquids

Question 15

the minimum safe approaching distance for rescues is?

Answer 15

5m

Question 16

On arrival to incidents involving electricity actions (general)?

Answer 16

locate responsible person

Question 17

If there is the possibility of high voltage present can f/f enter the risk area?

Answer 17

No - if any possibility at all no entry to risk area is to be made

Question 18

LFB gloves offer protection up to what voltage?

Answer 18

3300v

Question 19

minimum safe distance on overhead cables - using ladders/aerial appliances

Answer 19

10m (20m in training)

Question 20

Insulating materials at incidents involving electricty?

3 listed

Answer 20

PVC - toxic smoke

PCB (Polychlorinated Biphenyls) - insulating liquid (not always labelled)

SF6 (Sulphur Hexafluride) - insulating gas

Question 21

when should pavement covers be lifted?

Answer 21

NEVER! unless authorised person has confirmed it has been discharged

Question 22

On arrival at overhead cables?

Answer 22

request urgent attendance of National Grid

Question 23

what is classed as low voltage?

Answer 23

less than 1000AC or 1500DC

Question 24

What is high voltage?

Answer 24

greater than 1000volts ac (or 1500volts DC)

Question 25

FFs should not place themselves in a "corridor" how far either side if a overhead power line?

Answer 25

10m

Question 26

Ops procedure for pavement level cable systems fires?

Answer 26

Under no circumstances should crews seek to lift covers or further expose a pavement level cable system to extinguish the fire unless the authorized person has confirmed power isolated and residual current discharged

Question 27

What is low voltage?

Answer 27

less than 1000volts ac (or 1500 volts DC)

Question 28

What is UPS?

Answer 28

UPS is a Uninterruptible Power Supply (e.g battery banks)

Question 29

A person is seen to be lying on top of a transformer, switch, or anywhere else above ground level can we attempt a rescue?

Answer 29

No - they must not be touched until word is received from an authorized person of electricity authority that it is safe for rescue work to be carried out

Question 30

On arrival of Fire and Explosions in pavement level ducting 3 listed

Answer 30

immediate attendance of authorized person. cordon do not touch

Question 31

What will National Grid pylons and energy operators premises have?

Answer 31

unique markings/ identification plates this information must be included in any message

Question 32

Can rescue be made from electrical apparatus?

Answer 32

supply must be shut down! if the voltage is known to be 3300v or less LFB electrical gloves will provide adequate protection

Question 33

the minimum safe approaching distance for ladders or aerials without hose is?

Answer 33

10m (20 in training)

Question 34

Once current is switched of to high or low voltage installations is it rendered entirely safe?

Answer 34

No - residual charge of electricity may be present in apparatus - residual charge needs to be made safe by authorized person

Question 35

minimum safe distance - In dense smoke or flames approaching conductor

Answer 35

10m

Question 36

what is the distance (corridor) for firefighters and equipment when dealing with overhead power lines

Answer 36

10m either side of the overhead cable (measured along the ground)

Question 37

On arrival of Wind Turbines?

Answer 37

request isolation of any power supplies to the wind turbine and confirm that the blades have been "locked out"

Question 38

when can crews pass electrical warning signs or gain access into areas which have warning signs?

Answer 38

when authorised person is in attendance

Question 39

when the IC requests attendance of the authorised person, what else must be included in the message?

Answer 39

a) information from ID plates and signs | b) RVP or access restrictions as necessary

Question 40

At premises where a sub station has been provided within a building the transformer chamber/sub station will be situated against an outer wall. The wall and floors separating it from the remainder of the building will have at lease how many hours standard of fire resistance?

Answer 40

4hrs

Question 41

Can crews lift covers to further expose a pavement level cable system to extinguish fire?

Answer 41

No - unless the authorized person has confirmed that power has been isolated and residual current has been discharged

Question 42

ground and aerial appliance monitors should not be use within what distance of a live conductor?

Answer 42

30m

Question 43

at a premises where a substation has been provided within a building, the transformer chamber / sub station will be situated against an outer wall. How much fire resistance, within the walls and floors separating it from the rest of the building?

Answer 43

4 hours

Question 44

name the 5 specific hazards associated with electricity

Answer 44

``` electric shock fire explosion hazardous gases and liquids trip hazards ```

Question 45

What will supply or distribution facility display?

Answer 45

a unique identifier on a conspicuous indicator plate

Question 46

On arrival at a Substation?

Answer 46

request urgent attendance of authorized person

Question 47

minimum safe distance when using hand held jets on overhead cables

Answer 47

20m

Question 48

what is classed at high voltage?

Answer 48

over 1000 AC or 1500 DC