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>and I like the deep wrecks <60m Neither me or my associates have been bent >er my 20 years of diving and we dive using standard schedules. (Not US Navy) Neither have I (yet) >The thesis is that if you dive you are going to get bent. >Therefore prepare for it. Sound advice. I recommend a cellular phone to contact DAN (Australia in my case), oxygen and subscribe to an ambulance service. >The premise is that all dive tables have a certain bend >percentage, e.g. American Navy tables at 5% >This implies that if you dive to the limit of a certain table >that you have a certain probability of getting bent. Presumably The tables attempt to bring the diver back to the surface based on the idea that nitrogen disolved in the tissue and blood will form bubbles if the ascent is too rapid. DCI is more than just bubbles. A plethora of biochemical processes are initiated by the presence of bubbles in the blood. Individual variation to the rate at which the processes occur or whether they will occur at all make it impossible to accuratly predict whether a dive (all dives produce bubbles) will precipitate an episode of DCI. The tables are based on a mechanistic model and many are modified empirically but in the end it comes down to probabilities (like all biological processes). Decompresion tables work by keeping the total bubble surface area to a minimum. You don't need to 'push the envelope' to risk DCI. >The likelyhood of getting bent using a particular set of tables is a >function of age, fitness, health etc etc etc and not whether you are It's the etc etc etc than cannot be modelled hence there is always a chance you will get bent. >but hopefully divers adjust their schedules in accordance with their >life changes. How? >MOst divers dont get bent in practice, most divers enjoy an entire >lifetime of diving and dont get bent. Not true. Many experienced as well as inexperienced divers get bent. That's why hospitals and other places maintain recompression facilitites. The Hyperbaric Unit here has treated many experienced and careful divers, generally after non-provocative dives. >accepted is like a bushwalker expecting broken leg to be unavoidable. >When people get bent mostly its because of accident or excessive >abuse of the tables and not because its part of the show, its not. So bush walkers learn first aid and some even make plans for accidents like a broken leg. Decompression tables are not a shield againt DCI. They are a mathematical model with an associated (and measureable) failure rate. /Rat ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ shelps@ac*.ma*.ad*.ed*.au* Bring in the bottled lightning, a clean tumbler, and a corkscrew. DICKENS, CHARLES 1812-1870 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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