Emergency response for the electrical environment
When responding to an emergency involving the risk of electric shock , it is critical to ensure that :
• Isolation of the conductors occurs as soon as possible .
• Workers and members of the public are kept well clear of the hazard .
• For fallen or exposed electrical conductors , and to allow for step potential , a minimum safety clearance of ten metres for High Voltage or two metres for Low Voltage shall be maintained .
• All electrical apparatus shall be treated as live until proven de-energised : normal SAD as a minimum shall apply after confirmation that the conductors will remain de-energised .
• No approach within SAD shall be made to electrical apparatus until it is isolated and earthed / bonded by approved means as appropriate .
• At all times a member of the rescue crew must remain on site to issue verbal warnings to any person making unsafe approach to fallen or exposed electrical conductors . Access may also be controlled using barriers or signs .
Fallen or impacted powerlines
Any fallen conductor , or any conductor which is in contact with vegetation , can be lethal .
Stay well clear – just standing near them can be fatal .
Stay more than 10 metres away .
Always treat fallen powerlines as live even when they are broken . Never go near them or anything they may be touching , such as vehicles , metal fences or pools of water . Do not touch them with anything , even with nonconducting objects such as brooms or sticks .
Avoid touching anything that is in contact with a fallen power line . Vehicles may become energised by contact with the conductor and may be lethal .
Remember the risks associated with step potential . If there is a difference in potential between two areas on the ground , anyone who bridges that gap can be electrocuted .
Step potential can be thought of as ripples spreading out from the point of contact as the voltage carried in the ground diminishes . If you connect two points with different voltages , current will pass through you .
If a power line contacts your vehicle , remain in the vehicle if it is safe to do so . Roll down your window and make sure no-one else approaches the vehicle .
If you have to leave an energised vehicle ( EG , if a fire has started ), follow these steps :
1 . Remove all loose clothes .
2 . Keep your hands at your sides and jump clear of the vehicle , landing with your feet together .
3 . Keep both feet together and shuffle away from the vehicle without picking up your feet .
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