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Author
Cleary, T. G.
Title
Full-Scale Residential Smoke Alarm Performance.
Coporate
National Institute of Standards and Technology, Gaithersburg, MD
Report
Session 7,
Book or Conf
International Conference on Automatic Fire Detection "AUBE '09", 14th Proceedings. University of Duisburg. [Internationale Konferenz uber Automatischen Brandentdeckung.] September 8-10, 2009, Duisburg, Germany, 1-8 p., 2009
Keywords
fire detection | smoke detectors | experiments | sensors | photoelectric detectors | ionization detectors | cotton fabrics | polyester | polyurethane foams | ignition | chairs | smoke | toxic gases | egress | scenarios | optical density | fabric flammability
Identifiers
Available Safe Egress Time (ASET); Required Safe Egress Time (RSET); ISO/TS 13571; fractional effective dose (FED); alarm times for alarms; evolution of toxic gas and heat FED, and OD for a flaming fire; time to reach optical density or FED limits -- limit not reached
Abstract
A series of 24 full-scale fire experiments were conducted in a multi-room structure to examine the effects of alarm type (photoelectric, ionization, and dual sensor), alarm location, fabric type (cotton and polyester), polyurethane foam density, ignition scenario (smoldering or flaming), and room configuration on smoke alarm performance. The fire source was a chair mock-up consisting of a seat and back cushion of a specific fabric and foam density, resting on a metal frame. Each fire progressed for a time sufficient to produce multiple hazards (smoke, heat, toxic gases) throughout the compartment. Photoelectric, ionization, and dual photoelectric/ionization alarms were co-located at multiple locations to facilitate comparisons of each type of alarm. In the room of fire origin, a smoke optical density of 0.25 m-1 was reached before a fractional effective dose of 0.3 for either toxic gases or heat exposure. The available safe egress time (ASET) for both flaming and smoldering fires was sensitive to the imposed optical density limit. Further study is needed to deduce the impact of visibility-limiting smoke levels on the time needed to egress residential fires to justify any particular optical density limit value.