STSC Electrical Safety in Construction 2

Question 1

What is the voltage range classified as 'high voltage' under NFPA 70E for arc flash hazard analysis purposes?

Accepted Answer

Above 600V

Answer

NFPA 70E and OSHA classify voltages above 600V as 'high voltage,' triggering more stringent arc flash and electrical safety requirements including greater approach boundaries and higher-rated arc flash PPE.

Question 2

Under OSHA 1926.416, what does the term 'qualified person' mean in the context of electrical work on a construction site?

Accepted Answer

A person who has received training in and has demonstrated skills and knowledge related to the construction and operation of electrical equipment

Answer

A qualified person (electrical) under OSHA 1926.416 is one who has demonstrated skills and knowledge related to electrical equipment operation and construction, and has received safety training on the hazards involved.

Question 3

A power tool's power cord on a construction site shows evidence of insulation damage (cracked, frayed sheath). What is the CORRECT action?

Accepted Answer

Remove from service, tag out, and arrange for proper repair or replacement

Answer

Damaged insulation on a power cord is a shock and electrocution hazard. The tool must be immediately removed from service, tagged out to prevent use, and repaired or replaced by qualified personnel.

Question 4

Which of the following correctly describes the 'limited approach boundary' in electrical safety?

Accepted Answer

The closest distance an unqualified person may approach energized conductors without special authorization

Answer

The Limited Approach Boundary (NFPA 70E) is the distance from an exposed energized conductor within which unqualified persons may not enter unless escorted and protected. Beyond this boundary, workers need limited training; within it, full electrical safety precautions apply.

Question 5

What type of fire extinguisher is required for electrical fires on a construction site?

Accepted Answer

Class C (CO2, dry chemical, or clean agent)

Answer

Class C fire extinguishers are required for electrical fires. Class C designation indicates the extinguishing agent is non-conductive, preventing shock to the person using the extinguisher.

(STSC) Safety Trained Supervisor Construction Practice Test

(STSC) Safety Trained Supervisor Construction Practice Test

STSC Electrical Safety in Construction 2