A Study on the Performance of Current Smoke Alarms to the New Fire and Nuisance Tests Prescribed in ANSI/UL 217 8th Ed.
Thomas G. Cleary
Research was conducted on the performance of currently available smoke alarms to the new fire and cooking nuisance source tests specified in ANSI/UL 217 Standard for Safety of Smoke Alarms, 8th Edition. The standard calls for additional room-scale fire tests with smoldering and flaming polyurethane foam and a broiling hamburgers cooking test. The objectives of this research was to assess whether the new performance tests will foster a demonstrable enhancement in smoke alarm performance compared to a wide range of currently available smoke alarms and whether the single nuisance source test is representative of a range of cooking nuisance scenarios. There were 45 distinct smoke alarm models from seven different manufacturers used in the study. There were 14 ionization sensor models, 14 photoelectric sensor models, seven combination photoelectric and carbon monoxide sensor models, four combination ionization and carbon monoxide sensor models, four combination ionization and photoelectric sensor models, and two combination photoelectric and thermal sensor models. Six units of each model were used in the experiments for a total of 270 individual smoke alarms used in the study. The sensitivity of each alarm was measured in a smoke box with cotton wick smoke per the ANSI/UL 217 Standard. The measured sensitivities across the different models covered nearly the entire range of allowed sensitivities. Analysis of the results showed that no current smoke alarm model would meet the new test performance levels required in the 8th Edition of the Standard. Three models, all photoelectric sensor alarms, came closest to meeting the requirements. It was concluded that an across the board increase to the level of performance specified in the 8th Edition of the Standard would significantly improve the overall performance of smoke alarms by expanding the range of fire scenarios alarms must respond to while requiring resistance to nuisance alarms. The changes in the UL 217 8th Edition o