NITROX CERTIFICATION PROTOCOLS - REAL WORLD

[360GUY]

HELLO. I just got my NITROX certification. All went well. However, as my instructor was going through the training of testing my tank with the oxygen analyzer, she stressed over and over again how it's my responsibility to test the tank before each dive and to ensure that the proper labels are affixed to the tank (name, date, O2, etc)...She was very firm on these issues and I appreciated her passion for teaching...

OK, question. I recalled several months ago, I went to Cozumel to dive for a month. I was pretty new to diving and I dove with some pretty experienced, dive masters, instructors, etc...THEY ALL USED NITROX. (I didn't because I wasn't certified at that point)...But, I never saw any of them, EVER, test the tanks before the dives. I don't even recall seeing an O2 analyzer anywhere.

I dove the entire month with a reputable LDS, who I bet was pretty careful to test the tanks before setting up the dives...And of course, all dives went off without a hitch.

So...what gives? Is this one of those things where you train ONE WAY but perform real world functions ANOTHER WAY??? Should I invest in an O2 analyzer. When diving should I insist that I personally test my tank. Will I be holding up the whole operation?

OR...SHOULD I JUST GO ALONG WITH THE CROWD AND TRUST THAT THE LDS HAS DONE THE LEGWORK?

Thanks everyone for your help. ))

 

[BoltSnap]

What your instructor told you is the right way of doing it and is what you should follow. This is what I do since I started using Nitrox in 1990. I'd go even further and stress that you should own your own O2 analyzer and double check the numbers with the shop's numbers. ANY Nitrox station that doesn't give the chance for its clients to test the O2% and provide them with a properly working analyzer is a most terrible shop that should be avoided.

We have had several O2% toxicity accidents (deaths) because no one tested the O2% and people used the O2% beyond the MOD. It is your life, not the others', analyze your gas and make sure that you are getting what you are expecting and planning to use for your MoD.

 

[wetb4igetinthewater]

Never trust anyone for your own safety. Period.

 

[tursiops]

OP, following the crowd is often bad advice. Verify the gas you are going to use, if only to observe someone else doing it. Trust no one.

 

[lowwall]

Most of the dives I've done with nitrox there was an analyzer available.

But not all. Were the tanks labeled? I've dived with outfits that tested for you and wrote the percentage on a piece of masking tape stuck over the valve or on the tank neck. These are operators that I trust, so I haven't verified. If you aren't prepared to do that, ask the operator. They will normally have some process for you to personally test or at least witness the testing of your tanks.

 

[Marie13]

There seems to be a disconnect in practice between the tourist spots and local dive shops.

 

[360GUY]

Thanks for all the responses. Definitely seems to be a consensus.
Following the crowd and trusting others = BAD
Being responsible for my own life / dive = ONLY WAY TO GO

 

[wetb4igetinthewater]

Thanks for all the responses. Definitely seems to be a consensus.
Following the crowd and trusting others = BAD
Being responsible for my own life / dive = ONLY WAY TO GO

The normalization of deviance is rife in the scuba industry. Most times nothing happens. Very often fatalities go unreported.

 

[lowwall]

Please correct me if I'm wrong, but I remember Aldora on Cozumel provided pre-tested, labeled tanks. How many of the thousands of divers a year that go on their boats personally verify the tank contents?

For those unfamiliar with Aldora, they are one of the most respected ops on the island and they have their own fill station.

 

[loosenit2]

Something else for thought. Don’t only test the tank yourself, test within a few hours of your dive. Many shops use partial pressure blending, mixing richer mixes with air to get to the mix you want. It can take a while for the gases to fully blend and the reading can change over time. So don’t just analyze your own tanks, do it At the right time.