 Yount and others in 2000, and allows the choice of VPM-B and VPM-B/E, with six conservatism levels (baseline plus five incrementally more conservative ones).GAP allows the user to choose between a multitude of Bühlmann-based algorithms and the full reduced gradient bubble model, developed by Bruce Wienke in 2001, in its five conservatism levels (baseline, two incrementally more liberal and two incrementally more conservative).The personal decompression computer, or dive computer, is a small computer designed to be worn by a diver during a dive, with a pressure sensor and an electronic timer mounted in a waterproof and pressure resistant housing and which has been programmed to model the inert gas loading of the diver's tissues in real time during a dive.