rstofer
Contributor
I thought that most agencies were moving toward 30 fpm for recreational ascents with a 15-20 ft SS. With the emergence of the "tiny bubble models", I believe that research has shown that 30 fpm is an optimum rate. Faster or slower is not as good. The book "Deco for Divers" has a good discussion in Chapter 6.
Myself, for any recreational dive over 60 ft, I'll do a deep stop at half of max. depth for a minute. Then proceed to the SS, staying at 30 fpm +/-.
Of course I'm talking non-emergency, non-mandatory deco ascent.
The PADI tables are quite clear on the ascent rate: 60 fpm. In my view, you need to keep both feet on one side of the river or the other. Pick a dive plan methodology that you believe in and stick with it. These 'ad hoc' half-depth safety stops are NOT part of the PADI RDP. They are probably a good thing but you are mixing strategies. Any diver can come up with any scheme they want. Some may even be good. The problem is, who are you going to dive with? Do they believe in the plan?
With me it's pretty simple. I'm using a computer. I have decided, reluctantly, to join the digital age. So, that's the plan. We both dive to the most conservative computer and call it a day. I would be much happier just doing the old square profiles with the PADI tables. I may get back to this approach as soon as I get a boat. Beach dives don't lend themselves to square profiles. OTOH, they are so shallow I could bring double 130s and still not overstay the NDL.
The choice of PADI tables comes about because in 1989 NAUI changed their tables to the extent that repetitive dives that were quite satisfactory with the 1987 version and are still satisfactory with the PADI version, no longer work.
Richard