Spence Green

Dive Rite has just published an excellent article on O2 toxicity for CCR divers. Most of the article covers ground that is standard in CCR courses, except for this point:

The biggest mistake many CCR divers make is to elevate the pO2 at the end of the dive, during decompression. The logic is that they are at rest and therefore the risk of an O2 convulsion is reduced. This logic is correct, but it fails to consider several other factors.

CNS O2 toxicity is a result of cumulative damage in the cells. At the end of a CCR dive that requires decompression a significant amount of damage has occurred. If you then increase the pO2 you will increase the rate of damage and you will dramatically increase the risk of suffering an O2 convulsion, even if you are at rest.

That technique was recommended to me during basic training, and it is standard procedure for many of the CCR divers that I know. Never stop learning….