Charlie99
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OTOH, 10fpm is just fine as an ascent rate, provided you have the gas to meet your decompression option.mccabejc:All of that tells me that 10fpm is probably too slow, and 20-30fpm is probably a good target.
Initially, this thread was about what ascent rate the tables assumed. That isn't really the same as figuring out what is the best way to time and control and ascent. You continue to ongass the slower compartments while offgassing the faster compartments. Going too slow, loads you up excessively. Going to fast creates bubbles. Erik Baker's article on Deep Stops is a pretty good article explaining this balancing act.
Overall, though, if you play around with the simulator or any decompression program, you will find that in most cases the optimal ascent strategy is to have a variable ascent rate that gets slower and slower as you get closer to the surface. The easiest way to actually do this is by combining a reasonable ascent rate, such as 30fpm, with a series of stops.
When possible, I'll plan my dive such that after doing the deepest portion that I then go do a shallower dive for a while --- for example, go look at the bottom and propellor of a wreck, then the main deck, then the pilot house. Then my ascent effectively is starting from this shallower depth.
In those cases where there really isn't much between the bottom and the surface, then I'm balancing between 1) having enough gas for the ascent 2) having as safe an ascent/deco as possible and 3) Not getting too bored or impatient or wasting too much time on hanging mid-water vs. looking at whatever is down at the bottom.
My personal method is to use 30fpm ascent, 1 minute at 40', 1 minute or so extra in the 25' range, and then 3 minutes slowly going from 20' to 10'. On a practical basis, when I leave the bottom (or a the last level in a multiprofile dive) I decide at what runtime on my computer I will hit 40', 25/30', and the surface.
Having a preplanned ascent strategy that you use on most dives also helps in gas planning.