Decompression Schedule 3087907 63651337 2006-07-13T19:26:56Z Bobblewik 51235 units A '''Decompression Schedule''' is a series of increasingly shallower [[decompression stops]] for (usually) increasing amounts of time that a diver uses to offgas inert gases from the diver' body on the ascent to the surface to reduce the risk of [[decompression sickness]]. In a decompression dive, the decompression phase makes up a large part of the time spent underwater (in many cases its longer than the actual time spent a depth). The depth and duration of each stop is dependent on many factors, primarily the profile of depth and time of the dive, but also the [[breathing gas]] mix, the interval since the previous dive and the altitude of the dive site. The diver obtains the depth and duration of each stop from a [[dive computer]], [[dive tables|decompression tables]] or dive planning computer software. A deco diver will typically prepare several decompression schedules to plan for contingencies such as going deeper than planned or spending longer at depth than planned. An example of a deco schedule A dive to 130 ft on air for 10 minutes (the [[NDL]] is 5 minutes) Waypoint at 130 ft for 10:00 (13) on Air, PPO2 1.036, END 130 Deep Stop at 110 ft for 0:20 (13) on Air, PPO2 0.909, END 110 Deep Stop at 100 ft for 0:20 (14) on Air, PPO2 0.845, END 100 Deep Stop at 90 ft for 0:20 (14) on Air, PPO2 0.782, END 90 Deep Stop at 80 ft for 0:20 (15) on Air, PPO2 0.718, END 80 Deep Stop at 70 ft for 0:20 (15) on Air, PPO2 0.655, END 70 Deep Stop at 60 ft for 0:20 (15) on Air, PPO2 0.591, END 60 Deep Stop at 50 ft for 0:20 (16) on Air, PPO2 0.528, END 50 Deep Stop at 40 ft for 0:20 (16) on Air, PPO2 0.464, END 40 Norm Stop at 20 ft for 4:00 (20) on Air, PPO2 0.337, END 20 TOTAL DECO TIME: 7 minutes. DIVE RUN TIME: 20 minutes. The "Deep Stops" are a gradient reducing technique to limit bubble formation. The "Norm Stop" is a shallow deco stop. Typically this dive would be done on a lean [[nitrox]]. A deco dive would be longer. In an accelerated deco schedule, gasses with higher oxygen contents are used to speed up the decompression. This carries with it the risk of [[oxygen toxicity]], therefore situational awareness and depth control are a must. {{Diving-stub}}