A701.2 Electrical Emergencies

Question 1

__________ is the measure of flow of current through an object, such as the wiring in an electrical distribution system

Answer 1

Amperage

Question 2

It’s the amount of the _________ , not the ________ that determines the shock

Answer 2

amperage, voltage

Question 3

A current as little as _____________ can cause death

Answer 3

50 milliamperes

Question 4

Electric shock occurs when the body becomes a part of the electric circuit. This normally happens in one of three ways:

Answer 4

1) contact with both wires of a power source,
2) contact with one live wire and the electrical ground, and
3) an ungrounded metallic object that becomes energized while the person is in contact with the ground (e.g., an ungrounded aerial ladder coming into contact with overhead wires).

Question 5

The first priority at any electrical incident is

Answer 5

the safety of the first responders

Question 6

Wires Arcing/Power lines Down
If a wire is lying across the street or a pole is down, Remember that transmission wire has memory and can

Answer 6

tend to return to its spooled state if broken

Question 7

Ground level (pad mounted) transformers.
Do not attempt to use ____________ if on fire because the ground might be energized and the possibility for touch potential could be there

Answer 7

dry chemical or carbon dioxide (class ABC or BC) extinguisher

Question 8

Elevated Transformers
When a pole or pad mount transformer is interrupted for any reason, a breaker may trip the circuit. When that happens the

Answer 8

recloser relay will reclose the breaker back, re-energizing the circuit.

Question 9

Electric Utility transformers are filled with

Answer 9

mineral oil and PCBs

Question 10

4. Transformer oil is ignitable by

Answer 10

high temperature arcs

Question 11

Substations
Electro-magnetic fields near high voltage wires can result in

Answer 11

a shock without even touching a conductor connected to the power system.

Question 12

Underground Vaults
Transformers in the vaults are capable of

Answer 12

exploding with deadly force, shrapnel and super-heated oil.

Question 13

Aerial devices should be at least _____ from overhead utility lines unless the utility company verifies that the power is off

Answer 13

15’

Question 14

never operate an aerial ladder/platform within ___ of overhead wires

Answer 14

10’

Question 15

Firefighters should maintain a ___ clearance from electrical lines or equipment at all times

Answer 15

15’

Question 16

__________ can be extremely useful in locating potential fires inside walls, etc. It can indicate overheating wires, smoldering beams or studs. Also useful for locating overheating or faulty equipment in large open areas where there might be a strong electrical odor

Answer 16

Thermal Imaging Cameras (TIC’s)

Question 17

Any fire in a concealed area such as a floor, wall, a ceiling, an attic, a roof, or a soffit should be considered

Answer 17

electrical until proven otherwise

Question 18

Lights that flicker and dim or appliances and plumbing that give shocks are good indications of

Answer 18

an open neutral or faulty ground