Study on the Application of Carbon Monoxide Sensors for the Prevention of Unwanted Alarms

Abstract

This study analyzed the applicability of CO sensors through UL 268 unwanted alarm tests and real-scale unwanted alarm verification tests tailored to the domestic format. A comprehensive literature review indicated that the UL 268 fire test and the cooking nuisance test results revealed the fire-detection concentration and unwanted alarm concentration of CO and suggested that a real fire can be detected if the concentration of CO is above 17 ppm. Accordingly, during the pork belly and mackerel cooking events, which triggers frequent unwanted alarms in domestic multi-unit dwellings, the UL 268 domestic-type and real-scale unwanted alarm tests were conducted. The test results proved that the smoke detector sufficiently generated a fire alarm owing to the cooking by-products, as it measured up to 21.0 ppm, which is the maximum smoke concentration of the analog smoke detector under all conditions. However, as it was confirmed that the CO concentration was not more than 4.9 ppm in all experiments, it was confirmed that it was suitable for the fire and unwanted alarm-detection concentrations suggested in previous studies. Therefore, in the case of fire detectors, to prevent unwanted alarms in the future, it is important to distinguish between fire alarms and unwanted alarms further through crosschecking according to the applications of smoke and CO sensors.