scjoe
Contributor
Although NOAA does not follow the half time credit and treats the oxygen exposure as all disappearing at once after 24 hours, its statement that the credit is seldom taken into account for recreational diving is wrong. You can find a 24 hour limit for 1.6 of 150 minutes in DAN and IANTD and I believe SDI/TDI materials. Also, I think many of the computers on the market do give you surface interval credits.