diving 1/6's

[scubahhh]

i completely agree.

but how do you explain that on the second dive, using thirds, my penetration is
only 100 psi more than on the first dive, using sixths?

if the second is dangerous, then so is the first. 100 psi is nothing

Wait a minute... Quit worrying about the rules for a second and think about what you're saying: why would you want to follow a rule that tells you it's safe to dive longer and penetrate further on your second dive, when you have much less gas to begin with, than on your first?

BTW this is the first I've heard of the rule of sixths... where does that come from? Most people I dive with match gas and use thirds, but use them witha little safety fector built in... how much depends on the diver, the risk, etc. oh sure, we've done all the experiments and found that we can get out on about the same amount of gas it took us to get in, but I think it's important to remember that those experiments and exercises are just that, and not life-threatening situations. How sure are you that YOUR breathing rate won't go through the roof when it hits the fan? Your buddies?

 

[H2Andy]

BTW this is the first I've heard of the rule of sixths... where does that come from?

well, you've managed to miss the point of my question.... but



the rule of sixths is when you are doing single-tank penetration dives, but are
using double tanks. you simply treat the two tanks as if it were a single tank,
so instead of turning at thirds, you turn at sixths (i.e. you pretend you only
have one tank)

btw, welcome to ScubaBoard