Because of the critical role a ceiling membrane plays in the fire-resistance performance of a floor/ceiling or roof/ceiling assembly, any penetration through it must be protected. In the case of HVAC penetrations, protection comes in the form of a ceiling damper. 

Ruskin has released its new DFD-LP dynamic fire damper, which is rated for dual-direction airflow and can be installed vertically in walls or horizontally in masonry floors.

Greenheck says its new fire dampers are the largest in the industry.