Hazardous (Classified) Locations Flashcards

In a Class I, Division 2 location, which wiring method is generally acceptable?

Answer: Rigid metal conduit (RMC)

Rigid metal conduit is an approved wiring method for Class I, Division 2 locations per NEC Article 501.

Which NEC article covers Class II hazardous locations involving combustible dust?

Answer: Article 502

NEC Article 502 specifically addresses Class II locations where combustible dust is the hazardous material.

What is the primary purpose of sealing fittings in Class I hazardous locations?

Answer: To prevent the passage of gases, vapors, or flames

Sealing fittings in Class I locations prevent the passage of gases, vapors, or flames from one portion of the electrical installation to another.

A spray paint booth where flammable liquids are used would typically be classified as which hazardous location?

Answer: Class I, Division 1

A spray paint booth where flammable vapors are present during normal operations is a Class I, Division 1 location.

In the Zone classification system, Zone 0 corresponds most closely to which Division classification?

Answer: Division 1 only — continuous hazard

Zone 0 represents locations where ignitable concentrations of flammable gases or vapors are present continuously, corresponding to the most hazardous portion of Division 1.

Aluminum conduit is permitted in Class I hazardous locations under which condition?

Answer: When specifically listed for the hazardous location

Aluminum conduit may be used in Class I hazardous locations when it is specifically listed for use in that hazardous location.

Which of the following equipment markings indicates it is suitable for use in Class I, Division 1, Groups C and D locations?

Answer: CL I DIV 1 GP C,D

The marking 'CL I DIV 1 GP C,D' directly indicates the equipment is listed for Class I, Division 1, Groups C and D hazardous locations.