Perhaps the wording is wrong. Sorry, don't mean to be pedantic, however, Catastrophe = sudden disaster (Oxford Dict.)
I have seen "catastrophic" once and nobody walked away.
There are no doubt occasions when you have time to prepare, or as you are suggesting, taking unilateral action to save life. I hope those better qualified than I can give you the professional advice covering the scenarios whereby you call the shots!
Hope it never happens..........