FST Electrical Fire Safety 2

Question 1

Which condition is most directly responsible for insulation failure that leads to arc faults in building wiring?

Accepted Answer

Damaged, aged, or compressed wiring insulation

Answer

Physical damage, aging, heat exposure, and compression degrade conductor insulation over time, allowing conductors to contact each other or nearby combustibles and arc, potentially starting fires.

Question 2

What is the primary electrical fire hazard associated with aluminum branch circuit wiring in older residential buildings?

Accepted Answer

Aluminum oxidizes at connections, increasing resistance and generating dangerous heat

Answer

Aluminum forms an oxide layer at connections that significantly increases electrical resistance, generating heat at termination points that can ignite combustibles and cause fires.

Question 3

When performing a fire safety inspection of an electrical room, which finding represents the most immediate fire risk?

Accepted Answer

Combustible materials stored inside the electrical room

Answer

Combustible materials stored in electrical rooms create an extreme fire hazard because electrical arcs, sparks, or overheated equipment can readily ignite them in an area difficult to reach for suppression.

Question 4

Extension cords used as permanent wiring represent a fire hazard primarily because:

Accepted Answer

They are not designed for continuous use and may overheat over extended periods

Answer

Extension cords are designed for temporary, occasional use and lack the protection of permanent wiring; continuous use causes insulation degradation and overheating, which can ignite surrounding materials.

Question 5

What does the term 'thermal runaway' refer to in the context of electrical fire safety?

Accepted Answer

A self-reinforcing cycle where increased temperature causes greater resistance, generating even more heat

Answer

Thermal runaway occurs when rising temperatures increase resistance, generating more heat, which further increases temperature in a dangerous positive feedback loop that can destroy equipment and cause fires.

(FST) Fire Safety Technician Certification Practice Test

(FST) Fire Safety Technician Certification Practice Test

FST Electrical Fire Safety 2