Which standard is used for design and installation of electrical equipment in hazardous locations?

The standard used for the design and installation of electrical equipment in hazardous locations is primarily the NEC, which stands for the National Electrical Code, often referred to as NEC 70. This code specifically provides guidelines and requirements to ensure the safe installation of electrical wiring and equipment in locations where flammable gases, vapors, or dusts may be present.

NEC 70 outlines various classifications of hazardous locations and specifies the type of equipment that can be used in such areas to mitigate safety risks. This includes requirements for explosion-proof fixtures and intrinsically safe systems, ensuring that electrical installations do not serve as ignition sources for these potentially dangerous environments.

Other options like NFPA 70E focus on electrical safety in the workplace, OSHA outlines general safety mandates, and IEEE 1100 addresses power and grounding issues in industrial plants, but none specifically cover the design and installation aspects in hazardous locations the way NEC does.