|  | Public Health Safety | Public Health

NEMA Electrical Classifications

The National Electrical Manufacturers Association (NEMA) electrical classifications identify metallic and non-metallic product enclosures that meet the NEMA requirements and specification for its class. Typically installed in non-hazardous settings, these enclosures must meet certain environmental conditions and provide protection levels according to the NEMA classifications. The protection levels depend on the complete and correct installment of the enclosure.

  1. Applications

    • Architects, designers, engineers, inspectors and technicians use this information to conform to the requirements for enclosures for the U.S. market. The NEMA determines the guidelines for enclosures used for a wide range of products, including computers, instruments, cooling applications and other vital equipment--both indoors and outdoors. Currently, the NEMA has 16 classifications.

    Type 1

    • Designed for indoor application, this type of housing offers safeguards against incidental contact with dangerous parts. It also protects the equipment inside the casing from solid objects or foreign substances, like falling dirt.

    Type 2

    • Type 2 enclosures have approval for interior applications. It provides protection against people mistakenly touching unsafe components. The housing shelters the equipment on the inside of the unit from the penetration of solid external substances, including falling dirt, dripping or light splashing water.

    Type 3

    • This category of enclosure meets the specifications for indoor or outdoor use. Type 3 enclosures offer a measured safeguard for personnel against direct contact with hazardous components. It also protects the gear inside of the enclosure from solid foreign material, such as dust or falling dirt. It also shields the internal workings from rain, sleet, snow and windblown-dust. The enclosure can withstand the formation of ice on the enclosure's exterior.

    Type 3R

    • Designed for exterior and interior use, Type 3R enclosures shield personnel from incidental contact with dangerous components and protect the interior apparatus from falling dirt or the rain, sleet or snow. Ice build up on the exterior of the housing will not harm the enclosure the unit.

    Type 6

    • Type 6 classifications have a rating for interior or exterior applications. This category of enclosures allow for the temporary submersion of equipment under water. The housing is watertight and ice or sleet-resistant.

    Type 12K

    • Constructed for indoor use, the Type 12 category of enclosures have knockouts , but still provide the need protection against incidental contact and guard internal equipment from fibers, lint or circulating dust. This enclosure also guards against dripping and splashing water.

    Type 13

    • Intended for indoor use, Type 13 protects people against contact with dangerous components and the interior equipment. The enclosure protects against falling dirt, circulating dust and other airborne substances. Protection against water spraying and splashing from all directions and is oil tight.

Public Health - Related Articles