Stumped by the Code? NEC Requirements of Luminaires Installed in Wet, Damp, or Corrosive Locations
All questions and answers are based on the 2017 NEC.
Q. What does the Code require of luminaires to be installed in wet, damp, or corrosive locations?
A. Luminaires in wet or damp locations must be installed in a manner that prevents water from accumulating in any part of the luminaire. Luminaires marked “Suitable for Dry Locations Only” must be installed only in a dry location; luminaires marked “Suitable for Damp Locations” can be installed in either a damp or dry location; and luminaires marked “Suitable for Wet Locations” can be installed in a dry, damp, or wet location [Sec. 410.10(A)].
See Art. 100 definitions of “Location, Damp,” “Location, Dry,” and “Location, Wet.”
Luminaires installed in corrosive locations must be suitable for the location [Sec. 410.10(B)].
Q. What are the NEC requirements for the installation of luminaires in bathtub and shower areas?
A. No part of chain-, cable-, or cord-suspended luminaires, track luminaires, or ceiling paddle fans can be located within 3 ft horizontally and 8 ft vertically from the top of the bathtub rim or shower stall threshold [Sec. 410.10(D)]. (see Figure).
See Sec. 404.4 for switch requirements and Sec. 406.9(C) for receptacle requirements within or near bathtubs or shower stalls.
Luminaires located within the actual outside dimensions of a bathtub or shower to a height of 8 ft from the top of the bathtub rim or shower threshold must be marked for damp locations. If subject to shower spray, the luminaires must be marked for wet locations.
Q. What does the Code require for the spacing of luminaires installed under metal-corrugated sheet roof decking?
A. Luminaires installed under metal-corrugated sheet roof decking must be installed at least 1½ in. from the lowest surface of the roof decking measured from the bottom of the decking to the top of the luminaire [Sec. 410.10(F)].
Q. What are the NEC requirements for the installation of luminaires in clothes closets?
A. Only the following types of luminaires are permitted to be installed in a clothes closet [Sec. 410.16(A)]:
(1) Surface or recessed incandescent or LED luminaires with an enclosed light source.
(2) Surface or recessed fluorescent luminaires.
(3) Surface-mounted or recessed LED luminaires identified for use within the closet storage space.
Incandescent luminaires with open or partially open lamps and pendant-type luminaires aren’t permitted to be installed in a clothes closet [Sec. 410.16(B)].
Luminaires must maintain a minimum clearance from the closet storage space as follows [Sec. 410.16(C)]:
(1) 12 in. for surface-mounted incandescent or LED luminaires with an enclosed light source.
(2) 6 in. for surface-mounted fluorescent luminaires.
(3) 6 in. for recessed incandescent or LED luminaires with an enclosed light source.
(4) 6 in. for recessed fluorescent luminaires.
(5) Surface-mounted fluorescent or LED luminaires are permitted within the closet storage space if identified for this use.
