IEC Electrical Safety Practices 5

Question 1

What does 'flash protection boundary' mean in NFPA 70E arc flash terminology?

Accepted Answer

The distance at which incident energy equals 1.2 cal/cm², requiring arc-rated PPE beyond this point

Answer

The flash protection boundary (arc flash boundary) is the distance at which incident energy equals 1.2 cal/cm²; workers inside this boundary must wear arc-rated PPE.

Question 2

A portable generator on a construction site must have GFCI protection or an Assured Equipment Grounding Conductor Program (AEGCP). What is the key inspection requirement under the AEGCP?

Accepted Answer

Testing of all equipment before first use, after any incident, and at intervals not exceeding 3 months

Answer

The AEGCP requires equipment inspection before first use, after suspected damage, and at regular intervals not exceeding 3 months, with documented records.

Question 3

When should electrical workers perform a pre-task safety briefing?

Accepted Answer

Before beginning each new task or when conditions change during a shift

Answer

Pre-task safety briefings should occur before each new task and whenever conditions change, ensuring all workers are aware of current hazards and controls.

Question 4

What is the danger of 'touch potential' when working near a grounded electrical system experiencing a fault?

Accepted Answer

A worker touching grounded equipment can complete a circuit to ground if standing on earth at a different potential

Answer

Touch potential occurs when a grounded structure rises in potential during a fault; a worker touching it while standing on the earth can receive a shock due to the voltage difference.

Question 5

Which of the following is an example of an administrative control for electrical safety?

Accepted Answer

Requiring two-person teams for energized work above a certain voltage threshold

Answer

Administrative controls are procedural measures such as requiring two-person teams, as opposed to engineering controls like barriers or PPE.

IEC - Independent Electrical Contractors Practice Test

IEC - Independent Electrical Contractors Practice Test

IEC Electrical Safety Practices 5