sandsnow
Senior Member
- Location
- Southern California
Re: What is a plenum air space
There are fixtures listed for air handling. These would be for in a ceiling space used for air handling use. We've also called these return air ceilings. The fixture acts as the return air grill. You can view the UL marking guide here:
http://www.ul.com/regulators/luminaries.pdf
Scroll down to notes 19 & 20. To even confuse things more UL uses the term plenum.
When seperate RA grills are provided, then I agree any fixture with a metal housing is ok in in a return air ceiling or not.
There are fixtures listed for air handling. These would be for in a ceiling space used for air handling use. We've also called these return air ceilings. The fixture acts as the return air grill. You can view the UL marking guide here:
http://www.ul.com/regulators/luminaries.pdf
Scroll down to notes 19 & 20. To even confuse things more UL uses the term plenum.
When seperate RA grills are provided, then I agree any fixture with a metal housing is ok in in a return air ceiling or not.