Which NEC article covers electrical installations for hazardous locations?

• A. Article 600
• B. Article 500
• C. Article 320
• D. Article 410

Answer: (B)

Hazardous locations are addressed in Article 500 of the NEC. This article defines how to classify spaces that could ignite flammable gases, vapors, or dust (Class I, II, III locations and their divisions or zones) and sets the rules for what equipment and installation methods are allowed there. It requires equipment to be listed for the specific hazardous location and often to be explosion-proof, dust-ignition-proof, or intrinsically safe, depending on the classification. It also covers labeling, wiring methods, sealing, grounding, and inspection considerations to prevent ignition sources. Other NEC articles cover different topics—industrial control equipment, portable cords and flexible cables, or luminaires—so they don’t govern hazardous-location classifications and equipment in the same way.