lamont
Contributor
We still seem to be displaying a lot of helium fear.
The only skill you really need to be able to do to dive helium within recreational air limits is to be able to hold a stop and not blowoff or CESA to the surface. You don't need to be able to do a 20 minute, properly shaped deco from 110 to the surface with a gas switch -- you just need to be able to hang somewhere around 20 feet for a few minutes, to avoid being hurt. Helium goes into tissues fast, but it also comes out of tissues fast when you've got a driving gradient. Anyone that can get a DIRF tech pass, or intro to tech from some other agency should be able to hit that bar, and IMO those cards should really include being helium cards.
30/17 is also a pointless gas and just an example of helium fear (or else its a cert to give to people who shouldn't be diving to 100 feet with *any* gas because they can't control their buoyancy -- solution there is not to give those people cards until their buoyancy control is better and they can hold a blue water stop). I'd say that less than 30% helium is useless, but I'd get into an endless argument with the 25/25 guys over blending that mix via banked 32% vs. p-p blending 25/30...
The only skill you really need to be able to do to dive helium within recreational air limits is to be able to hold a stop and not blowoff or CESA to the surface. You don't need to be able to do a 20 minute, properly shaped deco from 110 to the surface with a gas switch -- you just need to be able to hang somewhere around 20 feet for a few minutes, to avoid being hurt. Helium goes into tissues fast, but it also comes out of tissues fast when you've got a driving gradient. Anyone that can get a DIRF tech pass, or intro to tech from some other agency should be able to hit that bar, and IMO those cards should really include being helium cards.
30/17 is also a pointless gas and just an example of helium fear (or else its a cert to give to people who shouldn't be diving to 100 feet with *any* gas because they can't control their buoyancy -- solution there is not to give those people cards until their buoyancy control is better and they can hold a blue water stop). I'd say that less than 30% helium is useless, but I'd get into an endless argument with the 25/25 guys over blending that mix via banked 32% vs. p-p blending 25/30...
