NEMA Ratings

Sealing Devices Customers often require National Electrical Manufacturers Association (NEMA) requirements be met for common sealing and venting.  Attached are some helpful references.  For more in-depth detail refer to the NEMA website.

NEMA 1 – General purpose.  Enclosures for indoor use.

NEMA 2 – NEMA 1 protection, plus protection against dripping and light splashing of liquids.

NEMA 3 – General purpose indoor/outdoor use weather resistance, with protection against falling dirt, rain, sleet, snow, and windblown dust.  Undamaged extenal ice b/u.

NEMA 3R – Same as NEMA 3 excluding protection against windblown dust.

NEMA 4 – Enclosures for general purpose indoor/outdoor use.  Protect against incidental contact and offer a degree of protection against falling dirt, rain, sleet, snow, windblown dust, splashing and hose-directed water.  Will remain undamaged by the external buildup of ice on the enclosure.

NEMA 4X – NEMA 4 + corrosion resistance.

NEMA 5 – General purpose, dust tight.  Also provide protection against falling dirt and dripping/light splashing of liquids.

NEMA 6 – Enclosures for indoor/outdoor with protection against falling dirt, hose-directed water and the entry of water during temporary submersion, and remain undamaged by external ice.

NEMA 6P – Same as NEMA 6 including protection against water entry after prolonged submersion at depth.

NEMA 7 – Indoor enclosures for locations classified as Class I, Groups A, B, C, or D.   Capable of withstanding pressures resulting from an internal explosion of specified gases, and contain the explosion sufficiently that an explosive gas-air mixture in the atmosphere will not be ignited. 

NEMA 9 – Enclosures for indoor use in locations classified as Class II, Groups E, F, or G.   Dust-tight.   Need to meet dust, temperature and gasket design tests.

NEMA 12 – Industrial enclosures for indoor use with protection against incidental contact, yet provide protection against falling dirt, circulating dust, drippingsplashing liquids.

NEMA 12K – Same as NEMA 12 with knockouts.

NEMA 13 – Industrial enclosures for indoor use with protection against falling dirt, dust, fibers, and spraying/splashing/water seepage, oil, and non-corrosive liquids.