I'll answer Mech's question. First of all, I am trained in deco procedures and O2.
I have two AL40 deco bottles rigged, one for 50 and one for 100.
Here's why I used 100 vs. 50:
Reason 1: The shop that does my fills was low on O2 the day prior to the dive and the shipment wasn't due in until the afternoon of the dive. My 100 was already filled, but the 50 was empty. Pretty straight forward.
Reason 2: Our limit on run-time was 60 minutes. To maximize BT, the dive done with 50 starting at 70' would allow 33 minutes BT. The same plan using 100 starting at 20' would allow 35 minutes BT. Not a big deal, but I used what gas I had available. Also, I only needed 8cf of 100 vs. 16cf of 50. I'll be able to use the bottle of 100 again for my next dive tonight without getting it topped off.
No magic, just what I had available. I know the 2 minutes are no big deal. That's why reason 1 is first.
I have two AL40 deco bottles rigged, one for 50 and one for 100.
Here's why I used 100 vs. 50:
Reason 1: The shop that does my fills was low on O2 the day prior to the dive and the shipment wasn't due in until the afternoon of the dive. My 100 was already filled, but the 50 was empty. Pretty straight forward.
Reason 2: Our limit on run-time was 60 minutes. To maximize BT, the dive done with 50 starting at 70' would allow 33 minutes BT. The same plan using 100 starting at 20' would allow 35 minutes BT. Not a big deal, but I used what gas I had available. Also, I only needed 8cf of 100 vs. 16cf of 50. I'll be able to use the bottle of 100 again for my next dive tonight without getting it topped off.
No magic, just what I had available. I know the 2 minutes are no big deal. That's why reason 1 is first.
