7.5.11 Downed Wires Flashcards
(14 cards)
What is the purpose of the Downed Wires standard operating guideline?
This standard operating guideline addresses safety and response guidelines for downed wires and other electrical emergencies.
Who does the Downed Wires SOG pertain to?
This SOG pertains to all personnel in this organization.
What must always be considered when dealing with downed wires?
The potential for electrical shock, electrocution, and secondary fires must always be considered.
What is ‘step potential’?
Step potential occurs when a person’s feet are simultaneously touching the ground in two areas with a voltage difference, allowing electricity to travel through the person.
What are the voltage categories for electrical distribution wires?
- Transmission line voltage – 69 kV.
- Primary distribution line voltage – 7,200 – 13,200 volts.
- Service line voltage:
- Pole to larger building – 277/480 volts
- Pole to small building or house – 120/240 volts.
What must be used when personnel are exposed to smoke at an electrical incident?
SCBA must be used whenever personnel are exposed to smoke at an electrical incident, including light smoke conditions.
What should be assumed about downed wires?
Downed wires must always be considered energized with potentially lethal current.
What is ‘Reel Memory’ in relation to downed wires?
Power lines tend to have ‘Reel Memory’ and may curl back or roll on itself when down.
What should be avoided when dealing with energized wires or electrical equipment?
Avoid using hose streams on or around energized wires or electrical equipment, as hose streams can conduct current.
How should apparatus be positioned in relation to downed wires?
Apparatus should be positioned at least one undamaged utility pole away from the scene.
What should be done if down power lines are in contact with a vehicle?
Do not touch the vehicle, assume it is energized, and advise occupants to remain inside until power is confirmed to be terminated.
What precautions should be taken at electrical sub-station incidents?
Use extreme caution, request the power company to respond, and secure the area to deny entry.
What should be assumed about smoke and fluids from electrical equipment?
Assume all smoke and fluids contain PCBs and avoid contact.
What is the protocol for entering a vault or manhole during an incident?
Under no circumstances will fire personnel enter a vault or manhole; if entry is necessary, the IC will request Northern Kentucky Technical Rescue Team.
