Electrical Installations

Equipment, wiring methods, and installations of equipment in hazardous locations must have the following characteristics:

• Intrinsically safe: Equipment and associated wiring approved as intrinsically safe is permitted in any hazardous location for which it is approved.
• Approved for the hazardous location: Equipment must be approved not only for the class of location, but also for the ignitable or combustible properties of the specific gas, vapor, dust, or fiber that will be present.
• Safe for the hazardous location: Equipment that is safe for the location must be of a type and design that will provide protection from the hazards arising from the combustibility and flammability of vapors, liquids, gases, dusts, or fibers involved.

The National Fire Protection Association (NFPA) publishes the National Electrical Code, known as NFPA 70. This standard contains guidelines for determining the type and design of equipment and installations that can be considered safe for the location. Those guidelines address electrical wiring, electrical equipment, and electrical systems installed in hazardous locations.

Provisions set out in 29 CFR 1926.407 provide marking requirements for specific equipment.

To learn more about Construction Electrical Safety visit our Construction Electrical Safety Online Training web page.