While we can compare tail-risks (some lower probability risks and many orders of magnitude more likely than others) I think most people, intuitively, use someth

While we can compare tail-risks (some lower probability risks and many orders of magnitude more likely than others) I think most people, intuitively, use something like a 1 in a 100 risk of a death (over a lifetime) or 1 in 10,000 acute chance. Anything over the floor is fair game, and the specifics are more around what is culturally acceptable. For comparison the lifetime risk from driving is something like 1 in 100, and from skiing (1 in 2000) making some assumption of average participation in both.