What are the Difference Between Dry, Wet, and Damp Locations?

(NEC) National Electric Code Definitions: UL Standard 1598 Definitions:

Dry Locations: A location not normally subject to dampness or wetness. A location classified as dry may be temporarily subject to dampness or wetness, as in the case of a building under construction.

Damp Location: Locations protected from weather and not subject to saturation with water or other liquids but subject to moderate degrees of moisture. Examples of such locations include partially protected locations
under canopies, marquees, roofed open porches, and like locations, and interior locations subject to moderated degrees of moisture, such as some basements, some barns, and some cold storage buildings.

Wet Locations: Installations underground or in concrete slabs or masonry in direct contact with the earth; in locations subject to saturation with water or other liquids, such as in vehicle washing areas; and in
unprotected locations exposed to the weather.


UL Standard 1598 Definitions:


Dry Locations: A location not normally subject to dampness, but may include a location subject to temporary dampness, as in the case of a building under construction, provided ventilation is adequate to prevent
an accumulation of moisture.

Damp Location: An exterior or interior location that is normally or periodically subject to condensation of moisture in, on, or adjacent to, electrical equipment, and includes partially protected locations.

Wet Locations: A location in which water or other liquid can drip, splash, or flow on or against electrical equipment. A wet location luminaire shall be constructed to prevent the accumulation of water on live parts, electrical components, or conductors not identified for use in contact with water. A luminaire that permits water to enter the luminaire (during the rain test of Clause 16.5.2 or the sprinkler test of Clause 16.5.3) shall be provided with a drain hole (Clause 13.4.3).

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