Columbia Shallows 2

Columbia Shallows, Cozumel, Mexico			N 20° 19.0' W 87° 1.0'
Dive Number 172		Buddy Neva, Jay	Surface temp 25°C	Starting pressure 3000psi
Depth 42ft	Visibility excellent	Time 40m	Water temp 27°C	Ending pressure 1500psi
NITROX		O2 % 33%	Depth Limit 107ft	CNS Toxicity 5%
Notes:	Well, this was interesting: Our resort had a problem with one of its air compressors, so we had picked up a few extra tanks from a neighbouring resort. While preparing for the dive, a detected a leak coming from the connection between the tank and Neva's regulator. When the problem persisted with other tanks we figured out that the loaner tanks were DIN-type instead of standard yoke-type that would match our regs. Jay asked if I would be OK to dive with one of the nitrox tanks they had and I agreed, so we swapped Neva to my [air] tank and I got a quick briefing in nitrox, and dove with it. A can't say I felt any different at the end of the dive, but was glad for the intro to nitrox. I would go on to complete the PADI Enriched Air course before we left Cozumel four days later. Neva successfully completed her last open water training dive, and it only remained for her to challenge the exam for certification card! There were lots of [hawksbill] turtles on this dive. Here's a picture of one.