Duct detectors must be installed in HVAC systems over how many CFM?

Duct detectors are critical components in fire protection systems, primarily used in heating, ventilation, and air conditioning (HVAC) systems. They are designed to sense smoke within the air ducts to prevent smoke from being circulated throughout a building during a fire event.

The installation of duct detectors is mandated by fire codes based on the airflow within the duct system. Specifically, these detectors must be installed in systems where the air flow exceeds a threshold to ensure effective monitoring and protection. The code generally specifies that duct smoke detectors should be installed when the HVAC system exceeds 2000 CFM (cubic feet per minute). This is due to the increased risk of smoke spreading quickly through larger volumes of air and ductwork.

By installing these detectors in systems over 2000 CFM, it ensures that any potential smoke or fire is detected early enough to mitigate the risk of spreading throughout the building, thereby enhancing the overall safety of the structure and its occupants.