How many of you have failed to analyze a tank that you thought had air?

[tplyons]

My aluminum tanks are "air-only", I don't have them labeled or cleaned for Nitrox use. Therefore, if I fill them, I know what's in them and don't analyze. If I don't fill them, I analyze to confirm that it is air as expected.

My steel tanks are O2 cleaned and labeled for Nitrox use. I do my own blending, so I analyze them at the time of blending (which I use to fill out the log), and then again once I get them home (sometime after 24 hours has passed to ensure that they are homogeneous since I use partial pressure blending to fill my Nitrox tanks) and label them appropriately with contents and MOD. If someone else fills them, I analyze them when picking them up (usually using their analyzer) and once before diving with my analyzer to be 100% sure.

It may seem a little anal, but I'd rather spend the extra few minutes each time and ensure safety.

 

[TONY CHANEY]

Interesting question. I am guilty of always failing to analyze a cylinder that I think has air. IF it is not placarded for enriched air use. Any cylinder placarded for EANx, I analyse before use. Now, your question has me pondering the wisdom of not doing it.

Same here. If it an EANx tank then yes but if an air tank then no. I am changing that now.

 

[elan]

Many people mentioned that if their tanks are not o2 clean or they do not have a sticker they do not bother analyzing. Can someone explain what kind of magic is used by such a tank to prevent high O2 mixes from getting into the tank? Can the tank read the stickers and automatically close the valve ?

 

[chrpai]

Many people mentioned that if their tanks are not o2 clean or they do not have a sticker they do not bother analyzing. Can someone explain what kind of magic is used by such a tank to prevent high O2 mixes from getting into the tank? Can the tank read the stickers and automatically close the valve ?

At my LDS they do PP blending and the tank monkey doesn't want to burn in a ball of fire. It's not magic, it's statistics.

 

[KeithG]

Let's try to put this is perspective.

How many of the "pro" testers check the air pressure in their car tires? What about doing a
pre drive visual inspection of theirs tires checking for nails, screws or other foriegn objects.

Nope, me neither. Never look at them.

 

[elan]

At my LDS they do PP blending and the tank monkey doesn't want to burn in a ball of fire. It's not magic, it's statistics.

I wish I had such a trust even in my own fills.

 

[RJP]

I don't breathe from any tank that I haven't analyzed myself, with the exception of air tanks I have filled myself from the "air only" side of our fill station.

 

[iluvtheocean]

i don't analyze the rental air tanks that i was getting - but they were 99.8% of the time from a shop that only has air (mod E) - anything i put in my own tanks I analyze unless the tank is emptied and filled at that same shop.

 

[victorzamora]

I just bought an O2 analyzer, and although I have rarely analyzed tanks before....the recent incident has made me wonder. For the safety of my fiancee (and mine, I guess), I have purchased a CO and an O2 analyzer. I will see how often I analyze air tanks with the O2 analyzer. I'm hoping to be religious with the CO analyzer. I don't own my own tanks, but that would be a better reason to analyze them as I imagine they'd all have an enriched fill sooner or later. The shop I used to work at only had the capacity to fill air, so we simply didn't analyze tanks. Once we started doing tech dives and more frequent trips to EANx suppliers with shop tanks, we started analyzing tanks that had nitrox in them until they got below 24%. All of our local diving was shallower than 60', so even 50% is compatible with local diving (at a PPO2 of 1.4).

One thing to be said that hasn't been: A lot of people say that there's no reason to analyze tanks just before you jump in. I agree with that. However, my preference would be to analyze as close as practicable to actually entering the water. The recent death was (we're pretty sure) caused by too long of a time between analyzing and diving. He analyzed a tank, it showed air. He grabbed what he thought was that tank...and ended up breathing 98% O2. Had he have analyzed at the hotel the night before, or at the site the morning of, or even at the edge of the water with all of his gear on....he could be here telling a story about how that scared him into analyzing more religiously. I'm not advocating O2 or CO analysis be performed no more than 5 minutes before a dive, I'm just saying that being "sure" your tank has air because you remember it right is too much complacency for my liking. My memory isn't that good, and my life is worth more than the 6 seconds it takes to analyze a tank.

 

[Rhone Man]

I was reading an article the other day which was talking about how absurdly risk adverse the Western world has become. Even when risks are negligible or inconsequential, people still insist on elaborate procedures and great expense.

It brought this thread to mind. Can't imagine why.

The bodies 'aint stacking up like cordwood. Deaths relating O2 toxicity for diving at recreational depths (we are, after all, in the Basic scuba forum) are officially somewhere between zero and "bugger all" each year for over a million active divers worldwide. I will continue to take the outrageous risk of not analysing my air fills to check they contain air (excluding tec dives of course).