Oily rags in an open trash can in the kitchen of an assisted-living facility spontaneously ignited, starting a fire that spread to a wall until heat activated a sprinkler. The three-story, wood-frame building, which measured 100 feet(30 meters), contained 80 unites in addition to common spaces. The building's fire alarm system monitored the water flow of the wet-pipe sprinkler, which was installed in compliance with the local code. A building occupant who heard the fire alarm activate discovered the fire in the kitchen and tried unsuccessfully to extinguish the blaze using a dry chemical portable fire extinguisher. by the time firefighters arrived at 9 p.m., however, a single sprinkler head had already extinguished the fire. Investigators determined that someone had improperly disposed of oily rags in the regular trash and that they had ignited spontaneously. The sprinkler spared the building significant fire damage, keeping losses to $5,000. There were no injuries.
Kenneth J. Tremblay, 2014," Firewatch", NFPA Journal, November/December 32.
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