Under which article would you find regulations for hazardous classified locations?

The correct answer is based on the structure and content of the National Electrical Code (NEC), specifically regarding hazardous classified locations. Article 510 provides specific requirements for the installation of electrical equipment in locations classified as hazardous due to the presence of flammable gases or vapors. This article outlines the necessary precautions and standards that must be followed to ensure safety and compliance in environments where such hazards exist.

Choosing Article 510 is appropriate because it explicitly addresses the regulations for Class I locations, where flammable gases, vapors, or liquids may be present, necessitating special equipment and installation methods to prevent ignition.

Other articles listed pertain to different hazardous environments or classifications. Article 511 focuses on the requirements for agricultural buildings; Article 513 relates to aircraft hangars; and Article 516 covers the use of electrical equipment in classified locations with combustible dust. While all these articles deal with hazardous locations, Article 510 is specifically targeted at the hazards associated with flammable substances, making it the pertinent choice for this question.