The human brain is incredibly bad at handling the kind of risk calculations that are relevant to activities where the risk increases dramatically from very very insignificant to very small. Like in deep air stunts.
These numbers are just off the cuff for demonstration; they're probably nowhere near correct, but work as an example. Let's assume an air dive to 80' and give that a risk of fatality of 1 in 200000 (from online UK statistics). Not bad, I'm happy to take the odds. I'd be even happy to recommend diving to others.
Now let's consider an air dive to, say, 400' and give it a guesstimate for fatality rate. This is a bit tricky, as I'm not aware of any reliable statistics and am not in the mood for extended digging. Those with better numbers, correct me if I'm completely off the ballpark. I'll try to be really generous towards the genetically superior macho cowboys of the olden ages, and toss in 1 in 2000, which is probably on the low side. That sounds still pretty okay, you could pull it off a hundred times with a fatality risk of 5%... But compared to the 80' dive it's 100 times riskier. Would I recommend it to anyone? No way.
And the odds could be much worse in reality, as I don't think too many people have done even a hundred dives that deep on air during their entire careers, and still not many of the wannabe-record-breakers are alive. With 1 death in 500, the risk would be 400 times higher compared to the 80' dive.
The problem here is that even with 1 in 500 death rate somebody could manage to do 10 or 20 400' air dives without even a big scare, and as a consequence draw the (wrong) conclusion that it was because of superior narcosis or tox tolerance/skills/cojones instead of dumb luck. I have no doubt that some of the deep air divers of past are/were exceptional divers, but those who survived were also very very lucky. But teaching deep air diving in 2010? Plain stupid.
//LN
These numbers are just off the cuff for demonstration; they're probably nowhere near correct, but work as an example. Let's assume an air dive to 80' and give that a risk of fatality of 1 in 200000 (from online UK statistics). Not bad, I'm happy to take the odds. I'd be even happy to recommend diving to others.
Now let's consider an air dive to, say, 400' and give it a guesstimate for fatality rate. This is a bit tricky, as I'm not aware of any reliable statistics and am not in the mood for extended digging. Those with better numbers, correct me if I'm completely off the ballpark. I'll try to be really generous towards the genetically superior macho cowboys of the olden ages, and toss in 1 in 2000, which is probably on the low side. That sounds still pretty okay, you could pull it off a hundred times with a fatality risk of 5%... But compared to the 80' dive it's 100 times riskier. Would I recommend it to anyone? No way.
And the odds could be much worse in reality, as I don't think too many people have done even a hundred dives that deep on air during their entire careers, and still not many of the wannabe-record-breakers are alive. With 1 death in 500, the risk would be 400 times higher compared to the 80' dive.
The problem here is that even with 1 in 500 death rate somebody could manage to do 10 or 20 400' air dives without even a big scare, and as a consequence draw the (wrong) conclusion that it was because of superior narcosis or tox tolerance/skills/cojones instead of dumb luck. I have no doubt that some of the deep air divers of past are/were exceptional divers, but those who survived were also very very lucky. But teaching deep air diving in 2010? Plain stupid.
//LN
