ESC ESC Arc Flash & PPE Selection

Question 1

What causes an arc flash event?

Accepted Answer

An electrical arc traveling through ionized air between conductors or to ground

Answer

Overloaded neutral conductors

Answer

A ground fault in a 120V circuit

Answer

Overheating of insulated conductors

Question 2

Which NFPA standard provides the requirements for arc flash hazard analysis and electrical safety in the workplace?

Accepted Answer

NFPA 70E

Answer

NFPA 70

Answer

NFPA 101

Answer

NFPA 72

Question 3

In what units is incident energy from an arc flash measured?

Accepted Answer

Calories per square centimeter (cal/cm²)

Answer

Joules per meter

Answer

Watts per square meter

Answer

BTUs per hour

Question 4

The arc flash boundary is defined as the distance at which incident energy equals:

Accepted Answer

1.2 cal/cm²

Answer

0.5 cal/cm²

Answer

4 cal/cm²

Answer

8 cal/cm²

Question 5

What minimum arc rating is required for PPE Category 1 per NFPA 70E?

Accepted Answer

4 cal/cm²

Answer

8 cal/cm²

Answer

12 cal/cm²

Answer

40 cal/cm²

Question 6

What does it mean for clothing to be 'arc-rated'?

Accepted Answer

The clothing has been tested and assigned an ATPV or energy breakopen threshold (Ebt) rating

Answer

The clothing can safely conduct electricity

Answer

The clothing is only flame retardant

Answer

The clothing is rated for chemical splash protection