KevinNM
Contributor
No, CNS Oxy tox is random largely. Tests showed that some people could last for an hour at high PO2s, the same people would then go into convulsions after a few minutes the next day. Sometimes the first symptom is a convulsion, other times they had the full spectrum of symptoms first. In addition, susceptibility to CNS hits is greatly increased by being immersed in water for reasons that are not well understood and having a convulsion in a chamber is usually just unpleasant, vs having one in the water - which is highly fatal. So you can usually handle a much higher PO2 in a dry chamber than you can safely handle in water and if you have a convulsion in the chamber the attendant just pulls the mask off and you breath the air in the chamber and recover.
Doing dangerous things for no real reason other then it's convenient is normalization of deviance. So yeah, the chance of something bad happening per minute you have a high PO2 is pretty small, but the impact can be very high. To go back to the classic study of this: Pieces of foam had been falling off the space shuttle tanks bipod ramp for years, hence it was safe to allow it to continue, right? What could a little piece of foam do to the shuttle?
Doing dangerous things for no real reason other then it's convenient is normalization of deviance. So yeah, the chance of something bad happening per minute you have a high PO2 is pretty small, but the impact can be very high. To go back to the classic study of this: Pieces of foam had been falling off the space shuttle tanks bipod ramp for years, hence it was safe to allow it to continue, right? What could a little piece of foam do to the shuttle?