Development of unlimited duration excursion tables and procedures for helium-oxygen saturation diving

Excursion ascents were performed during a series of experimental helium-oxygen saturation dives ranging between 150 and 1000 fsw to study the limits of multiple and extended duration excursions both deeper and shallower than the saturation depth. The distance a diver can safely ascend without decompression following saturation was found to be a function of depth, increasing from 75 ft at a saturation depth of 225 fsw to 180 ft at 1000 fsw. Initiation of saturation decompression immediately after an excursion was found to be safe. This information is incorporated into new U.S. Navy Unlimited Duration Excursion Tables and Procedures for Saturation Diving.