The National Electrical Manufacturers Association (NEMA) defines standards used in North America for various grades of electrical enclosures typically used in industrial applications. Each is rated to protect against personal access to hazardous parts, and additional type-dependent designated environmental conditions. A typical NEMA enclosure might be rated to provide protection against environmental hazards such as water, dust, oil or coolant or atmospheres containing corrosive agents such as acetylene or gasoline. A full list of NEMA enclosure types is available from the NEMA website.
Enclosure types
Below is a list of NEMA enclosure types; these types are further defined in NEMA ICS 6: Enclosures standard. Each type specifies characteristics of an enclosure, but not, for example, a specific enclosure size. Note that higher numbers do not include the lower-numbered tests. For example, types 3, 4 and 6 are intended for outdoor use, but type 5 is not.
NFPA is National Fire Protection Association, and NEC is National Electrical Code (U.S.A.)
NEMA enclosure ratings are similar to IEC IP Codes and can offer the same protections, but cannot be mapped directly. See IP Codes & NEMA.