History of decompression research and development gets too high when compared to the ambient pressure. These bubbles, and products of injury caused by the bubbles, can cause damage to tissues known as "decompression sickness" or "the bends". The immediate goal of controlled decompression is to avoid development of symptoms of bubble formation in the tissues of the diver, and the long-term goal is to also avoid complications due to sub-clinical decompression injury. The symptoms of decompression sickness are known to be caused by damage resulting from the formation and growth of bubbles of inert gas within the tissues and by blockage of arterial blood supply to
Decompression practice depth and duration of each stop from a dive computer, decompression tables or dive planning computer software. A technical scuba diver will typically prepare more than one decompression schedule to plan for contingencies such as going deeper than planned or spending longer at depth than planned. Recreational divers often rely on a personal dive computer to allow them to avoid obligatory decompression, while allowing considerable flexibility of dive profile. A surface supplied diver will normally have a diving supervisor at the control point who monitors the dive profile and can adjust the schedule to suit any contingencies as they occur.