Take 100 divers, each performing 100 divers in their lifetime. One of those people will encounter double regulator failure. I am not a diver, so I am not sure whether this is a definitely fatal scenario. However, if that is the case it would imply that 1% of divers that perform 100 dives will die from this one mode of failure.<p>Given that I am sure there are many other ways that one could die in submerged caves like these, as the people in the article did, I imagine that the actual &#x27;lifetime probably&#x27; of death in frequent cave divers is much higher.