Nov 01 2009

Fire & Smoke Dampers No Longer Required

Category: Fire & Smoke Dampers,Questions and AnswersBKeyes @ 2:53 pm

Q:  The hospital I work for recently completed its sprinkler upgrade and wants to reduce maintenance by removing some fire and smoke dampers in the walls.  What is the procedure for removing fire and smoke dampers within these walls? May we just permanently prop-open the wall dampers and leave them in place or should those dampers be removed since they no longer function as fire safety devices.

A: First let’s look at the requirement for smoke and fire dampers. NFPA 101-2000 LSC, section 9.2.1 requires HVAC ductwork to comply with NFPA 90A, which specifies when fire dampers are required. Generally speaking, fire dampers are only required in 2-hour fire rated walls or greater, or in any fire rated vertical shaft wall. They are not required in 1-hour fire rated walls with fully ducted systems on both sides of the rated wall, and they are not required in non-rated walls. Therefore, in this situation, it is permissible to remove them.

Section for existing construction (and section for new construction) has an exception that says smoke dampers are not required in smoke compartment barriers with fully ducted HVAC systems in smoke compartments protected with sprinklers. Therefore, it is permissible to remove smoke dampers from fully ducted HVAC systems in smoke compartments protected with sprinklers.

Your question asks what the procedure is to remove these dampers. It has always been my position to actually remove the dampers entirely and repair the ductwork. This would be considered “best practice” as it eliminates the dampers from being mistaken for devices that are supposed to work and be tested. However, many Authorities Having Jurisdiction (AHJ) will accept a damper that is no longer required to be in the wall, to be disabled and secured in the open position. If you choose to go this route, I would suggest you add a sticker on the outside of the damper identifying that it is no longer in service and is disabled.