PETER WILMSHURST
T H E D I V I N G D O C


IN A recent Diver news article describing a deep technical dive, I was interested to read that a member of the expedition had been bent. Often magazine articles give glamorous descriptions of high-risk expeditions, without mentioning accidents that I know happened.
I read one article describing an expedition in which fewer than 100 dives were done by a dozen divers. It did not mention the bends.
I saw two of the divers, who wanted to be checked out for causes of the bends they had suffered. They told me that two other divers on the expedition were also bent.
If one-third of this group was bent doing fewer than 100 dives, the hit-rate was very high. This is something that readers should know. It is unethical for magazines to give a glamorous impression of a high-risk activity without letting readers know the risks.
Diving is a risk sport. There is always the possibility of suffering decompression illness. For amateur divers we think in terms of one bend in every 10,000 or so dives. This does not mean that all dives have an equal chance of a bend occurring one in 10,000 times.
Risk increases with depth of the dive, but the relationship is not a simple linear one. The risk of diving to 50m is not five times the risk of diving to 10m, but very much greater.
Diving is like mountaineering. The top of Everest is some ten times higher than the hills in the Lake District, but the risk of climbing Everest is far more than ten times greater than the risk of a ramble in the Lakes.
The risk of climbing increases exponentially with altitude. There are physiological problems such as low partial pressures of oxygen. There is the unexpected avalanche.
Mountaineers know that survival involves an element of chance. To push the limits you must be better prepared, more experienced and fitter, but you also have to be luckier.
Mountaineering articles mention what went wrong - so must articles in diving magazines.

from: divernet