Why are NEMA ratings important for heat tracing?

NEMA (National Electrical Manufacturers Association) ratings are standards used in the United States to classify the degrees of protection provided by electrical enclosures against environmental factors such as dust, moisture, corrosion, and other elements. These ratings help ensure that electrical equipment is suitable for specific applications and environments. 

NEMA ratings typically consist of a numeric code that indicates the level of protection provided by an enclosure. The higher the number, the greater the level of protection.

When installing heat trace systems, several NEMA ratings are important to consider ensuring the proper protection of the equipment and to maintain safe and reliable operation, especially in environments where elements, such as moisture and corrosion could affect the system’s performance. 

Some of the key NEMA ratings to consider for heat trace systems include:

  • NEMA 4 - Indoor or outdoor use primarily to provide a degree of protection against windblown dust and rain, splashing water, hose-directed water, and damage from external ice formation.

  • NEMA 4X – Heat trace systems installed in outdoor or harsh environments where exposure of moisture and corrosive agents is a concern can benefit from a NEMA 4x enclosure to ensure durability and longevity. This rating provides protection against ingress of solid foreign objects, dust, and water as well as additional corrosion resistance.  

  • NEMA 6 – For heat trace systems installed in areas where water submersion or high levels of moisture are expected. A NEMA 6 enclosure may be necessary to prevent damage and maintain operational integrity. 

  • NEMA 7 – This rating is specifically designed for hazardous locations where flammable gases, vapors, or combustible dust may be present. Heat trace systems installed in these sorts of environments must comply with NEMA 7 requirements to ensure safety and prevent ignition risks.

  • NEMA 12 – Used for many indoor industrial applications where exposure to dust, dirt, and dripping water is the primary concern.  

Consulting with manufacturers and industry experts can help determine the most suitable NEMA rating for a particular application. Drexan’s metallic components are suitable for installation with all PipeGuard self-regulating cables which meet NEMA 4 requirements. 

For rating standards in the United States, download NEMA Ratings for a complete list of enclosure types. For the most current information and complete details pertaining to hazardous locations in Canada, refer to the Canadian and National Electrical Codes