An Experimental Study on the Effectiveness of Fire Dampers in Kitchen Exhaust Ducts

This study experimentally investigated the effectiveness of fire damper installation and fan operation for suppressing the spread of fire through exhaust ducts during cooking-related fires. Two types of duct systems, barbecue table and kitchen cooking exhaust ducts with different diameters, were constructed, and fire dampers were installed inside the ducts. The effects of fire damper operation, number of installed dampers, and fan operating conditions on the internal temperature of the ducts were analyzed. The results showed that the operation of fire dampers physically blocked the propagation path of heat within the ducts, whereas the operation of fan reduced the heat accumulation inside the ducts. Under combined fan and fire damper operation, a temporary temperature increase occurred immediately after damper activation. However, the maximum temperature in the section between the fan and fire damper was approximately 47.9 °C, which was approximately 50% lower than the maximum temperature of 97.6 °C observed when the fire damper was not operating. In addition, in sediment fire experiments, although a temporary backflow of heat occurred after damper activation, the overall temperature increase was mitigated.