A performance comparison of 14 rescue breathing apparatus was undertaken as an assessment of past and present worldwide technology. Rescue breathing apparatus are self-contained, close-circuit breathing apparatus used for entry into areas having atmospheres that are immediately dangerous to life and health. Apparatus tested were the Biomarine BioPak 45, 60, and 240; the Draeger BG4 and BG-174A; the Litton LITPAC II; the MSA Custo, 4500 II Air Mask, Chemox, and McCaa; the Sabre Selected Elevated Flow Apparatus (SEFA); the Scott Rescue-Pak; the Siebe Gorman Aerorlox and Proto Ten; and the Survivair LP-120. Physiological parameters monitored during the testing were average inhaled CO2 and O2, minimum inhaled CO2, inhaled wet-and dry-bulb temperatures, and peak inhalation and exhalation breathing pressures. The metabolic demand on the apparatus was 1.35 L O2/min, the first beginning 10 min into the test and the second beginning 10 min before the end of the rated duration of the apparatus. Results presented include apparatus service life and test-averages of monitored physiological parameters. Schematic drawings and photographs of the apparatus are also included.
