US Navy decompression models and tables

The US Navy has used several decompression models from which their published decompression tables and authorized diving computer algorithms have been derived. The original C&R tables used a classic multiple independent parallel compartment model based on the work of J.S.Haldane in England in the early 20th century, using a critical ratio exponential ingassing and outgassing model. Later they were modified by O.D. Yarborough and published in 1937. A version developed by Des Granges was published in 1956. Further developments by M.W. Goodman and Robert D. Workman using a critical supersaturation approach to incorporate M-values, and expressed as an algorithm suitable for programming were published in 1965, and later again a significantly different model, the VVAL 18 exponential/linear model was developed by Edward D. Thalmann, using an exponential ingassing model and a combined exponential and linear outgassing model, which was further developed by Gerth and Doolette and published in Revision 6 of the US Navy Diving Manual as the 2008 tables.

Besides the air and heliox tables for open circuit bounce dives, the US Navy has published a variety of hyperbaric treatment schedules, decompression tables for open and closed circuit heliox and nitrox, tables incorporating surface decompression on oxygen, a system for modifying tables for use at high altitudes (Cross corrections), and saturation tables^{[broken anchor]} for various breathing gas mixtures. Many of these tables have been tested on human subjects, frequently with an result of symptomatic decompression sickness, and for this reason their test results are considered some of the most reliable available.

US Navy tables have generally been freely available for use by the general public, and have often been modified to further reduce risk, as commercial and recreational divers do not always fit the physical requirements for military divers, may not have a recompression chamber on site to manage decompression sickness on those occasions when it does occur, and may prefer to operate at a lower risk than military personnel. Several recreational diving tables were originally based on US Navy diving tables.