Posted by northcoast diver on February 16, 2005 at 11:36:09:
In Reply to: Another problem with computers posted by Eric S on February 16, 2005 at 08:08:55:
I can think of various solutions.
First is diving with EAN 35 with 1 hour surface intervals between dives. That gas gives you virtually unlimited dive time, if you are also wearing single 80 cu ft tanks each. 35 lets you dive to 100 ft, which is the NACD cavern limit. Then you would never approach an NDL limit. The 80 cu ft tank becomes the limiting factor not the NDL time for EAN 35.
Second, establish a generous reserve for your tank pressure, such as Rule of Thirds, or 1000 PSI. Then the first person to reach that point determines the turn around point. This would normally occur long before you reach your NDL limit, whatever computer you are each using.
The beauty of EANx is that since the N2 fraction is lower, the NDLs and longer, and the offgassing of N2 is faster, so NDLs become lass restrictive. With a single tank, tank pressure normally becomes the limiting factor before the NDLs do.
I do not know of anyone who straps on double tanks so that they could push the NDLs of EANx. I suppose that is possible, only that by the time divers buy their own twin tanks, they are usually smart enough not to push NDL times, or else they are doing decompression already, and NDLs are no longer an issue.