Duct Smoke Detector Installation Location

The international mechanical code section 606 2 2 also states that unless multiple air han dling systems share common supply or return air ducts or plenums duct detection is not required in the supply air system.

Duct smoke detector installation location.

If the detector is. Duct smoke detectors should be located in the hvac area between 6 and 10 duct equivalent diameters of straight uninterrupted run. Standard location when factory mounted will be on the side opposite the damper actuator. The inlet sampling tube is to be located between blades to avoid blockage of the airflow past the tube.

Prior to the installation of the damper and smoke detector. For proper air sampling duct pressure should be a minimum of 0 01 inches of water. To ensure correct operation install the duct detector using the following guidelines. In the areas where smoke detectors become inaccessible designers should include smoke detection controls remote from the inaccessible area.

The duct detector should when possible be located a minimum of six duct widths downstream from a source of turbulence bends inlets or deflection plates. At these locations air flow is less turbulent and the air smoke mixture should be more homogenous refer to nfpa 90a 72 and 101 for more information. Due to smoke dilution in the ducts the duct detectors will respond more slowly than an area detector. Designers should also remain aware that duct detectors may not substitute for area smoke detection.