Looking for a more aggressive computer algorithm.

[redacted]

I don't think it's possible to get such data to compare different computers, unless perhaps you want to torture hundreds of mice for such experiments.

Nor am I saying any computer is dangerous. There is enough safety margin or people would be getting bent using them. But the margin of safety must be greater with a more conservative algorithm. It has to be, because your dive time is shorter and/or it prescribes a deco stop slowing ascent. Decreasing dive time and/or slowing ascent has to increase safety margin with respect to DCS at least.

Anther issue as that article I linked pointed out, there may be injury over years of diving that may be very subtle and we're not aware of, a bit like the boxer suffering from boxer's dementia after years of fighting. There was at least one study that found spinal-cord lesions in asymptomatic divers. In my mind it's better to err on the side of caution.

Adam

A fence located 100 ft from a cliff appears to provide a greater "margin of safety" than a fence located 10 ft from the cliff. Yet, that may not make the 100 ft standoff fence any safer. OTOH, it may even be more tempting to violate the 100 ft fence because it is obviously such a large safety margin.

After experiencing a conservative computer (Scubapro EDI) I went shopping for a computer that would safely put me as close to the edge as I could find. I can always manage it to make my dive more conservative. It is much more difficult to manage a conservative computer to make your dive safely more liberal.

 

[fnfalman]

I
Nor am I saying any computer is dangerous. There is enough safety margin or people would be getting bent using them. But the margin of safety must be greater with a more conservative algorithm. It has to be, because your dive time is shorter and/or it prescribes a deco stop slowing ascent. Decreasing dive time and/or slowing ascent has to increase safety margin with respect to DCS at least.

Anther issue as that article I linked pointed out, there may be injury over years of diving that may be very subtle and we're not aware of, a bit like the boxer suffering from boxer's dementia after years of fighting. There was at least one study that found spinal-cord lesions in asymptomatic divers. In my mind it's better to err on the side of caution.

Adam

The Haldanean/DSAT model has plenty of conservatism built in. How much safety margin is enough?

If one is to worry that much about DCS then might as well stay home and take up golf or something.

There's no difference between diving a computer programmed with Haldanean/DSAT algorithm than diving with tables, except that in this case the computer does the rounding up instead of the diver doing the rounding up.

One doesn't need a conservative computer to tell one's NDL time. Just look at the dive table for the deepest depth that you're going to dive at that particular dive site, find the maximum allowable bottom time and subtract some times from that. If NDL time is 30-minutes, then chop it back to 20 or 25-minutes.