A Procedure for Selection of Diving and Aviation Personnel Resistant to Decompression Sickness Based on Tests in a Low Pressure Chamber.

Abstract : In a group of young, lean student divers resistance to bends was determined by two 2-hour simulated ascents to 38,000 feet in the low pressure chamber, rate of ascent 5,000 feet per minute. During the first exposure the most susceptible individuals, poor group (22 men) developed bends or chokes during the first hour at rest, and the somewhat less susceptible, fair group (40 men) developed bends during the exercise period of the second hour. During the second exposure consisting of 2 hours with exercise at the same altitude, 50% of the most resistant individuals, good group (30 men), remained free from symptoms while 96% of the less resistant individuals, fair group (27 men), developed bends or chokes. In a third exposure consisting of 2 hours of rest at 38,000 feet and serving to check the observations made during the first and second tests, 12 out of 27 men previously classified as fair failed to remain symptoms free, while only 3 out of 38 men previously classified as good developed symptons. (Author)