Sprinkler protection of manufactured homes with sloped ceilings using prototype limited water supply sprinklers

Three full-scale fire tests were conducted in a commercial manufactured home 4.3 m wide by 18.3 m long with 10° sloped ceilings. The purpose of the tests was to determine the performance of limited water supply (LWS) sprinklers under a sloped ceiling and to determine whether the minimum distance allowed between sprinklers could be reduced from 2.4 m to 1.8 m. Six prototype LWS sprinklers were installed at a spacing of 1.8 m by 2.4 m in the living room/kitchen area, which measured 4.0 m by 7.2 m. The ceiling and walls were combustible in all three tests, and the room was ventilated by three open windows. The fuel package for all three tests consisted of a vinyl-covered chair with polyurethane padding, double-layered curtains (100% polyester and 50% cotton/50% polyester), and a wooden end table. In the first test, the fuel package was placed in a corner; in the second test, along the wall under the apex of the ceiling between two sprinklers; and in the third test, along the longitudinal wall between two sprinklers. In all tests, no more than two sprinklers actuated. The flow rate with one and two sprinklers operating was 38 pm and 49 pm, respectively. Flow after the first sprinkler actuation was maintained for 10 minutes when one sprinkler actuated and for 7 minutes 40 seconds when two sprinklers actuated. The total flow in each of the three tests was 380. In all three tests, the sprinklers prevented the curtains and wall paneling from becoming involved in the fire during sprinkler operation. Tenability based on carbon monoxide concentration and gas temperature at the 1.5 m level was maintained in all three tests.