A gray color unit body quickly identifies the SS1P, SS2P, and SS3P as plenum-rated products.

How to determine adequate subfloor plenum pressure in computer and electronic equipment rooms.

The FabricAir® Ceiling Diffuser outperforms metal diffusers in efficiency, aesthetics      and installation speed, while offering architects customizable interior accents. 

A special concern from a life safety perspective is that plenums are home to combustible materials as well as various pipes, cables, and wires that may yield toxic fumes and smoke.