STSC Electrical Safety in Construction

Question 1

Under OSHA 29 CFR 1926.403(i)(2), what is the minimum safe working clearance required in front of electrical equipment rated over 600V that is likely to require servicing while energized?

Accepted Answer

3 feet

Answer

2 feet

Answer

4 feet

Answer

6 feet

Question 2

What is the primary purpose of a Ground Fault Circuit Interrupter (GFCI) in construction electrical systems?

Accepted Answer

To detect current leakage to ground and interrupt the circuit before electrocution can occur

Answer

To prevent overloading circuits with too many tools

Answer

To protect electrical equipment from voltage spikes

Answer

To prevent electrical fires from overheated wiring

Question 3

A construction site is implementing an Assured Equipment Grounding Conductor Program (AEGCP) as an alternative to GFCIs. How often must cord sets, receptacles, and equipment be visually inspected under this program?

Accepted Answer

Before each day's use

Answer

Weekly

Answer

Monthly

Answer

After any suspected damage

Question 4

What type of electrical hazard is created when a worker stands on wet ground and touches a grounded metal structure that has developed an insulation fault, causing current to flow through the worker's body to ground?

Accepted Answer

Contact voltage (step potential / touch potential)

Answer

Arc flash

Answer

Electrical overload

Answer

Electromagnetic induction

Question 5

Under OSHA Lockout/Tagout (LOTO) requirements for construction (29 CFR 1926.417), when must lockout/tagout procedures be applied?

Accepted Answer

Before performing service or maintenance on any machine or equipment where unexpected energization or startup could harm workers

Answer

Only when working on electrical systems over 480V

Answer

Only during shutdowns lasting more than one shift

Answer

Only when the circuit breaker is more than 50 feet from the work area

Question 6

An STSC supervisor notices extension cords on the job site that are coiled up while in use, running through standing water, and are not rated for the load being applied. Which of these conditions presents the MOST IMMEDIATE life-safety risk?

Accepted Answer

Extension cords running through standing water

Answer

Coiled cords generating heat

Answer

Undersized cords overheating under load

Answer

All conditions are equally dangerous