Incidents involving Electricity PN769 Flashcards
where would a sub-station be situated in a building?
On the outside wall
The walls and floor of the sub-station building have how long in relation to fire protection?
4 Hours
What is dangerous about smoke near electrical lines?
The air surrounding the cable can ionise, arching from cables to trees/buildings or brigade equipment
In a fire situation what are the hazards that could be present?
Large quantity of fuels present e.g. Methanol, Propane, Hydrogen, Methane, Chlorine and Oxygen
Oil filled transformers
Insulating materials creating vast quantities of toxic and irritant smoke
Some transformers are filled with carbon dioxide or vaporising liquid
Where should you make your arrival to?
Main entrance unless pre-planning determines a better entrance
What is the maximum attendance time for an authorised person?
2 hours
In case of fire and the responsible person is present but can not confirm if power is isolated without entering the compartment, what should be the actions of the IC?
IC must assess risk vs benefits
If any possibility remains as to whether high voltage remains, then no entry is to be made
If it can be identified as low voltage by responsible person then actions can be taken with suitable controls put in place
What is the idea of Carbon Dioxide or vaporising extinguishing media?
Neither damage electrical switch gear
What is the minimum distance a ground monitor or Aerial can be used on live switch gear?
30m
Unless otherwise marked, what power voltage will we assume battery banks to be and what can we use to protect ourselves?
LV
Electrical Gloves
If you see a person be seen laying on top of a transformer, switch or anywhere else above ground level, what should your actions be as IC
They must not be touched until the responsible person confirms it is safe for rescue work to be carried out
If high voltage apparatus is above ground what is the minimum height and what must be in place?
2.5m is the minimum height and then a protective screen must be placed around it
What voltage is deemed to be ‘High Voltage’?
1000vAC or 1500vDC
What is the minimum safe approach distance of overhead lines or electrical substations to perform a rescue?
5m
What is the minimum safe approach distance for using a ladder or aerial (No hoses)
10m but 20m in training
