Protection of airline flight attendants from hypoxia following rapid decompression

To determine the maximum time for working flight attendants to effectively initiate airline passenger mask donning after onset of a rapid, severe decompression, we exposed 10 subjects in two series of tests to a decompression from 6,500 to 34,000 ft (2,000 to 10,400 m) in 26 s, followed by descent at 5,000 ft/min (1,500 m/min) while subjects performed a light-to-moderate workload. Supplemental oxygen was provided in one series from a compressed oxygen system, and in the other series from a chemical oxygen generator system. With delays to mask doning of 10 and 15 s, no hypoxic effects occurred. With delays of 20 and 25 s, increasing hypoxic effects, similar in frequency for the two systems, occurred. Some technical problems in mask donning contributed to losses of consciousness with the latter two delays.