Analyzer: Nitrox vs. CO

[JanK]

As for CO problems, they are probably as rare as being bitten by a shark which is as rare as being eaten by wild pigs.

I'm not sure I agree with that.

Remember that SB is being sued as a consequence of discussion about CO related death and mutiple poisonings and about CO contaminated fills before that particular incident.

And just a few minutes ago DandyDon posted a message where he described measuring relatively high concentrations of CO in tanks.

 

[Bubbletrubble]

My second hand dry suit is slowly turning into a colander and I still need a main dive light!

I don't see myself buying a CO analyzer anytime soon!

Colanders are for making pasta.
There are some new drysuits priced in the $1000-$1200 range.
You need a primary dive light. I hear you guys have dark water up there in the PNW.

I'd prioritize exposure protection and lighting over an O2/CO analyzer and...gasp...even UW photography equipment. (I can't believe I just wrote that.)

 

[Sas]

I would want a lot of other scuba stuff before I got either one... I might eventually but only if I have run out of other stuff to buy.

 

[lowviz]

..........So, if you were going to buy one instrument, which would it be, an oxygen analyzer for Nitrox diving, or a carbon monoxide analyzer for all diving?
..................

An oxygen analyzer AND a trans-fill whip.

 

[Soakedlontra]

Last Sunday we re-filled our tanks in a different town and dive shop. I smelled the air from the tank in the shop and it smelled of bread dough...I must say that I wished I had a CO analyzer to find out what there was in those tanks. We decided to go head and dive with them. While breathing that air through the regulator I did not feel an 'aftertaste' of bread dough, though. At the end of the dive we were both OK. The shop was not located in a boat yard where folks build or 're-model' boats but in a quiet street. Later while driving with our windows open we noticed that the air had a similar smell which came from a nearby paper mill. What I am getting at is that the air that we breath is polluted no matter what! I bet that there is no shop in the world that can fill tanks with pristine clean air! The filters do what they can to not letting some pollutants into the tanks but ultimately we end up breathing polluted air and we are just kidding ourselves thinking otherwise.

 

[CriticalMass]

What I am getting at is that the air that we breath is polluted no matter what! I bet that there is no shop in the world that can fill tanks with pristine clean air! The filters do what they can to not letting some pollutants into the tanks but ultimately we end up breathing polluted air and we are just kidding ourselves thinking otherwise.

I note that this is an old thread, but IMO it needs a final clarification.

Folks, the CO issue deserves a lot more respect than you gave it here. I've been spending time reading through the quite lengthy discussions on this board about last February's events in Cozumel, and they're attention-getters. If you convulse and loose consciousness at 60-70 feet, business picks up quickly, and you may not survive it.

But the crucial point not being picked up here is that CO is undetectable by "smelling it". The training litany is that we should reject any breathing air that "smells or tastes bad", but CO is ODORLESS AND TASTELESS. What that means is, unlike the air with a "bread smell", if CO's in there by itself, you're not going to know it. And it only takes a tiny bit to take you out. In the US, the accepted limit for CO is 10 ppm. That's not much.

You may have all the confidence in your LDS's compressor, and you may decide to use remote unknown dive shop's compressors without question. But there's no way for you to know when they last serviced it, when they last replaced the filter(s), whether the equipment has a CO monitoring system with automatic shut-off if CO is detected....all that kind of stuff. And CO can be generated internally in a compressor which is running hot and has even a slight amount of combustion of the lubricating oils inside the unit. That's an important consideration - even if the intake filtering system is at peak efficiency, if CO creation occurs inside the compressor, CO can be present in the fill air it generates.

Bottom line: Without some way to know what's in the gas you're breathing, you're taking all this stuff on habit and blind faith, and if it turns out to be a bad bet, you can die. IMO, a CO detector should be at the TOP of the list of equipment to buy, not the bottom. I'm in the process of deciding which one I'm going to buy at the present time.

What's your life worth?

 

[DandyDon]

I just found this thread while looking for another one on a real CO hit with multiple injuries. The nativity about real CO risks from trusted Ops with good names is still wide spread obviously.

I have chosen a CO analyzer first because although I have just recently received a Nitrox Card I cannot afford to dive on Nitrox all the time so regular air is going to be the gas that I will be using most of the time.

Yeah, and Nitrox providers seem to always have Nitrox analyzers, or you can dive air, but Ops generally have their heads hidden on the CO issue. "No problems yet" just doesn't hold anymore and the hidden problems are being discovered more.

I'd save money for most anything else also. I rate buying a CO analyzer about equal with getting insurance against being struck by lightning.

Let me guess how much you have actually studied the risk.

I've rarely been anyplace that supplied Nitrox and didn't have an O2 analyzer to use. Yeah occasionally you will run into one with an O2 sensor a bit past it's prime but it's rare it's a big problem.

I have yet to see anyplace with a CO detector. I may get one at some point. I wouldn't be hugely surprised if some ops start making one available as a service as they become cheaper and easier to use, but I'm not expecting them to be as universal as O2 analyzers since there's currently nothing saying they "have" to have one.

Yeah that needs to change, but neither DAN nor Padi want to admit that scuba is not as safe as they have claimed it was. It's always interesting the first time someone has their tank checked for them and a reading is found. :shocked2: As CO analyzers become more common among divers, it happens. We had to turn a boat around our last day in August.

Unfortunately, it's also common for question air problems to arise but no one knows anyone with an analyzer. If you go to DEMA, stop by the Analox booth to to see their new portable EII CO unit.

Can't you be your own CO detector? I mean, CO doesn't exactly occur in abundant quantities in nature. Just have a look around at the compressor system in use, on a boat is the air intake anywhere near the exhaust for the boat, the compressor itself, propane fired stoves etc? At your LDS are they sucking the air in at street level? Is there an idle car parked infront of the air intake?

Nope. Electric compressors with clean intakes are quite capable of producing their own internally.

 

[sambolino44]

I guess I'm not really surprised at the responses, perhaps a bit disappointed. People believe what they want to believe, despite all the evidence. Only in this case there isn't much evidence either way. I'm generally skeptical, so I'd rather make an effort to find out myself, rather than just assuming everything's OK. Not a very popular option.

It's not that I'm looking for another expensive piece of gear to buy and maintain, and add another task to my dive routine. It's that, just as I make an effort to find out what's in the food I eat (another unpopular option), I'd like to know what's in the high-pressure air I breathe.

 

[DandyDon]

I guess I'm not really surprised at the responses, perhaps a bit disappointed. People believe what they want to believe, despite all the evidence. Only in this case there isn't much evidence either way. I'm generally skeptical, so I'd rather make an effort to find out myself, rather than just assuming everything's OK. Not a very popular option.

It's not that I'm looking for another expensive piece of gear to buy and maintain, and add another task to my dive routine. It's that, just as I make an effort to find out what's in the food I eat (another unpopular option), I'd like to know what's in the high-pressure air I breathe.

Padi used to require quarterly air tests by one of the two accredited labs, and one of them stated they saw a 3% failure rate - and when they failed, they often failed at very dangerous levels.

Sadly, when bad air is suspected in a thread report here on SB, the divers usually cannot find a CO tester. I know of a current case there in the Puget area; their awaiting the results from the fill shack tests sent away - like their lawyer would allow them to admit guilt.

Lovely island you live on there. I was just chatting with another Seattle resident who has never been up there, much less the ferry tour of the San Juans.

 

[String]

O2 analyser without any doubt. If you dive nitrox you want an O2 analyser. Getting that wrong can kill you very quickly on a dive.

A CO analyser ive never heard of outside the paranoid on this one internet forum and certainly never met anyone owning one, asking for one or in fact any situation where one would be useful.

The incidences of CO poisoning are absolutely tiny, way way less than the number of O2 tox incidents. CO analyser also doesnt check for anything else potential nasty and undetectable in the gas mix either.