An evaluation of a self contained breathing apparatus was conducted by NIOSH. The unit, which carried NIOSH/MSHA approval, was worn by a firefighter who died at the scene of a fire. The unit was visually inspected. Laboratory bench tests performed included evaluations of the inhalation and exhalation breathing resistance, rated service time, alarm assembly, and bypass and gas flow. A quality assurance test was also conducted. The regulator of the unit was found to be in the demand mode, and the facepiece exhalation valve was in the pressure demand mode. The unit's performance on the tests met NIOSH specifications. Based on laboratory tests, the authors conclude that the unit was intact, performed within NIOSH specifications, comprised the proper components, and was in good working condition; however, operation of the unit with the regulator in the demand mode and the facepiece exhalation valve in the pressure demand mode may reduce protection. Operation of the respirator in these modes is not approved by NIOSH.
Division of Safety Research, NIOSH, TN-00731, 7 pages