NEMA protection categories
National Electrical Manufacturers Association
The National Electrical Manufacturers Association (NEMA) is a standards organisation in Washington, USA, which publishes a number of technical standards but does not test or certify products itself.
The following NEMA classification outlines the protection of personnel from incidental contact with equipment and the protection of enclosures from external factors.
| Protection category | Explanation |
| NEMA 1 | Indoor use, protects against falling dirt. |
| NEMA 2 | Indoor use, protects against falling dirt and dripping water. |
| NEMA 3 | Outdoor use, protects against rain, sleet, snow and windblown dust; also protects against damage from external formation of ice on the enclosure. |
| NEMA 3R | Outdoor use, protects against rain, sleet, snow; also protects against damage from external formation of ice on the enclosure. |
| NEMA 3S | Indoor or outdoor use; protects against rain, sleet and windblown dust; furthermore, external mechanisms remain operable when ice laden. |
| NEMA 4 | Indoor or outdoor use, protects against windblown dust and rain, splashing and hose-directed water; also protects against damage from external formation of ice on the enclosure. |
| NEMA 4X | Indoor or outdoor use, protects against windblown dust and rain, splashing and hose-directed water and corrosion; also protects against damage from external formation of ice on the enclosure. |
| NEMA 5 | Indoor use; protects against falling dirt, settling airborne dust, lint, fibres and flyings, as well as dripping non-corrosive liquids. |
| NEMA 6 | Indoor or outdoor use, protects against falling dirt, hose-directed water and the ingress of water during occasional, temporary submersion at a certain depth; also protects against damage from external formation of ice on the enclosure. |
| NEMA 6P | Indoor or outdoor use, protects against hose-directed water and the ingress of water during longer periods of submersion at a certain depth; also protects against damage from external formation of ice on the enclosure. |
| NEMA 12 | Indoor use; protects against falling dirt, circulating dust and dripping non-corrosive liquids. |
| NEMA 13 | Indoor use; protects against dust, falling dirt, splashed water and oil as well as non-corrosive coolants. |
