A blitz of bends: decompression sickness in four students after hypobaric chamber training

This paper reports three cases of type II and one case of type I decompression sickness occurring in a group of nine vigorously active US Army parachutists who took a hypobaric chamber HALO (high altitude-low opening) training flight to a maximum altitude of 9,908.5 m (32,500 ft). After the cases of decompression sickness were diagnosed and treated, the aviator mask regulators were checked and found to be functioning properly; the oxygen supply was analyzed and found to be pure. All cases fully recovered after treatment on US Navy Diving Table 6 and have returned to full military duty. This HALO training profile is not in use with either the US Navy or the US Air Force and should probably be considered unsafe for future use in training.