ASP Electrical Safety 5

Question 1

What is 'step potential' and why is it hazardous near a downed power line?

Accepted Answer

The voltage difference between two points on the ground surface that can drive current through a person's legs and body

Answer

The voltage required to step up current in a transformer

Answer

The minimum voltage to energize a step-down transformer

Answer

The rated stepping load on an electrical platform

Question 2

What does the term 'flash protection boundary' mean in NFPA 70E arc flash analysis?

Accepted Answer

The distance beyond which arc flash PPE is no longer required because incident energy is below 1.2 cal/cm²

Answer

The boundary of the electrical room where flash photography is prohibited

Answer

The radius around a panel within which only licensed electricians may work

Answer

The distance at which an arc flash will cause automatic circuit breaker tripping

Question 3

Which class of fire extinguisher is appropriate for energized electrical equipment fires?

Accepted Answer

Class C

Answer

Class A

Answer

Class B

Answer

Class D

Question 4

An arc flash hazard analysis identifies an incident energy level of 25 cal/cm² at the worker's position. What arc flash PPE category (per NFPA 70E) is required at minimum?

Accepted Answer

Category 3 (25 cal/cm² min rating)

Answer

Category 1 (4 cal/cm² min rating)

Answer

Category 2 (8 cal/cm² min rating)

Answer

Category 4 (40 cal/cm² min rating)

Question 5

What distinguishes a 'qualified person' from an 'unqualified person' under OSHA electrical standards?

Accepted Answer

A qualified person has been trained and demonstrated skills and knowledge related to electrical equipment construction and hazards

Answer

A qualified person holds a licensed electrician's certificate issued by the state

Answer

A qualified person has more than five years of electrical work experience

Answer

A qualified person wears all required PPE when working near electrical equipment

Question 6

Which condition makes a portable electrical tool most likely to create a ground fault shock hazard for the user?

Accepted Answer

A damaged or missing equipment grounding conductor in the supply cord

Answer

Using the tool in an area with low ambient humidity

Answer

Operating the tool at a voltage rating lower than the supply voltage

Answer

Using a heavy-duty extension cord with the tool

Question 7

What is the purpose of applying an insulating cover or guard on nearby energized conductors when working in close proximity?

Accepted Answer

To prevent accidental contact with energized parts that are within the limited or restricted approach boundary

Answer

To reduce the conductor's operating temperature

Answer

To improve the conductor's current-carrying capacity

Answer

To protect conductors from physical damage by falling tools