Hi,
Here's the situation:
I only can bring 1 tank (not oxygen clean) and do 3 dives per day while on the island. First dive, I bring my own nitrox since my mainland shop fills from a Nitrox bank and doesn't require cleaned tanks. The next 2 dives where I fill on the island use regular air.
I used to just set my computer for EAN 32 on the first dive then air the next two dives but I was wondering if I should use a lower nitrox setting instead. I would assume this math makes sense, but I just want to make sure I'm not missing something...
*First dive (EAN 32) - Dive to 600 PSI, from 3K.
*Second dive (Air) - ((600/3000)*32)+((2400/3000)*21) = 23.2 EAN. Dive down to 500 PSI.
*Third dive (Air) - ((500/3000)*23)+((2500/3000)*21) = 21.3, so just 21.
I would cool down the tank by dipping it in the water for 30 seconds before doing these calcs. And of course know to change the weighted average base if my fill is +/- 3K PSI. Also, the dives don't go deeper than 90ish feet so no worry about PPO2.
Here's the situation:
I only can bring 1 tank (not oxygen clean) and do 3 dives per day while on the island. First dive, I bring my own nitrox since my mainland shop fills from a Nitrox bank and doesn't require cleaned tanks. The next 2 dives where I fill on the island use regular air.
I used to just set my computer for EAN 32 on the first dive then air the next two dives but I was wondering if I should use a lower nitrox setting instead. I would assume this math makes sense, but I just want to make sure I'm not missing something...
*First dive (EAN 32) - Dive to 600 PSI, from 3K.
*Second dive (Air) - ((600/3000)*32)+((2400/3000)*21) = 23.2 EAN. Dive down to 500 PSI.
*Third dive (Air) - ((500/3000)*23)+((2500/3000)*21) = 21.3, so just 21.
I would cool down the tank by dipping it in the water for 30 seconds before doing these calcs. And of course know to change the weighted average base if my fill is +/- 3K PSI. Also, the dives don't go deeper than 90ish feet so no worry about PPO2.