How much Carbon in a tank is no good at 130 ft ???

[Doctor 302]

Patty Clarkson from Analox was super nice to talk to on the phone & had e-mailed me the following.Thanks Patty

The standards differ from Country to Country: 3 ppm in the UK and 10 ppm in USA. What we cannot predict is an individual diver's metabolism of CO. Frankly if you are a long time smoker, you will withstand 10 ppm of CO exposure much better than a non-smoker.


At the end of the day, properly compressed Scuba Grade air shouldn't have any more than 3 ppm CO in it. It's a dangerous game to ponder at what maximum level of CO I can dive with. CO show's its deadly effects much more on ascent when the benefits of partial pressure oxygen are diminished. This is a particularly dangerous time for a diver.

Bottom Line: I won't dive a tank with more than 3 ppm CO.


My Best Regards,

Patti L. Clarkson
Vice President, Sales

 

[Tigerman]

That's what I'm thinking as well 5 - 7 ppm. 10ppm only if I really have too.
Here's to hoping Egypt has some good quality air

Ive never died diving any of the 100 or so tanks of nitrox (and a few air) Ive had in Egypt so its probably fine.
Ill let you know if my dieing status changes tho

 

[DandyDon]

Ive never died diving any of the 100 or so tanks of nitrox (and a few air) Ive had in Egypt so its probably fine.

Which proves nothing. The facts, including warm climate, little government control, little chance of suing for negligence, etc. would suggest that finding a bad tank there would be greater than at many other destinations. Nonetheless, the only way to know what's in your tank is to test it; no test, no knowledge.

 

[Tigerman]

Which proves nothing. The facts, including warm climate, little government control, little chance of suing for negligence, etc. would suggest that finding a bad tank there would be greater than at many other destinations. Nonetheless, the only way to know what's in your tank is to test it; no test, no knowledge.

Well, yeah. My post was obviously a joke.
However, there is a signifacant diving industry in Egypt as well, just as in Mexico and the caribbean and Ive never heard of any CO-related incidents (I have however heard of a few other kinds of incidents - and witnessed one). That may of course just be dumb luck, but if you dont choose from the shabbyest shops down there theire as professional as anywhere else in the world.

 

[manni-yunk]

Well, yeah. My post was obviously a joke.
However, there is a signifacant diving industry in Egypt as well, just as in Mexico and the caribbean and Ive never heard of any CO-related incidents (I have however heard of a few other kinds of incidents - and witnessed one). That may of course just be dumb luck, but if you dont choose from the shabbyest shops down there theire as professional as anywhere else in the world.

Perhaps you were not listening then as there are several document CO incidents and others that are ex post facto suspected but no one looked for at the time.

Your "joke" was in poor taste for such a subject, and innapropriate.

BTW - I have ammended my confortable limit - Im no longer saying 5-7 and now looking for less than 3. Ive also used the Analox tester on a few sets of my doubles and came up with zero - so I was happy.

 

[Tigerman]

Ive heard of many CO incidents, especially in Mexico lately, but not in Egypt.
If you find it poor taste or innapropriate to poke fun at a generalized subject, Ill leave be as your opinion but I disagree (obviously)

 

[bleeb]

Perhaps you were not listening then as there are several document CO incidents and others that are ex post facto suspected but no one looked for at the time.

I posted the following thought in another thread, but maybe it'll get more discussion here. CO causes a loss of the blood stream's O2 carrying capacity. While a large CO dose may be fatal in itself, lower otherwise non-fatal doses would reduce a person's exercise tolerance, increasing their vulnerability to panic or even medical events from over-exertion. So how many of those all-too-frequently-discussed panic or medical-related accidents and near-misses in warm water vacation spots actually had CO as a contributing or even a gating factor (i.e. person wouldn't have panicked if CO hadn't lowered their panic threshold)?

 

[DandyDon]

Ive heard of many CO incidents, especially in Mexico lately, but not in Egypt.

Which could mean only that Egypt is better at covering up such? Dive accidents happen there too, but when the bodies and tanks are recovered - are blood & tank CO levels tested and published? Is the equipment for such even available? The only way to know and dive with confidence is to test tanks before use. If an accident happens to someone, try to get to their tank and test it yourself with a trusted witness before authorities secure it, say it's to help in treatment if the diver is alive - but you have to have a CO analyzer handy of course.

 

[TSandM]

Nobody has mentioned the thing that would be the biggest concern for me. The presence of any detectable CO in a tank of compressed gas is an indication that something in the compressor setup is faulty. In addition to CO, the failures can result in entraining hydrocarbons from lubricant oils or fuel. There is at least one diving incident I know of where I believe it was toluene was eventually identified as a potential factor. The presence of ANY carbon monoxide in a tank would be cause for me to refuse to dive it, especially for technical diving.

 

[John C. Ratliff]

You are forgetting your diving physics. I just posted this into a LinkedIn thread from the American Industrial Hygiene Association (AIHA):

Liberty Mutual recommends actual testing once a year for Grade D breathing air. Most facilities that charge fire department or diving cylinders do this testing. Here is one I found by googling "Grade D Breathing Air Testing."

TRI Air Testing :: Grade D Air Testing


I am trying to find out what my dive shop, and what our safety supply house, do for this testing. I will post again if I get better information. But I do know that CO is the major hazard. There are CO testing is a topic for diving, as there have been fatalities for CO in breathing air for divers. This has to do with the laws of partial pressures, whereby the as the pressure increases, the partial pressure increases so that the TLV of 25 ppm at the surface can be reached with only 6 ppm in the breathing air at 5 atmospheres absolute pressure (10 meters = 1 atmosphere; 40 meters, or 132 feet is 5 atmospheres absolute pressure). At that pressure, the partial pressure rules (Dalton's Law, Dalton' Law of Partial Pressure ). show that the 6 ppm is the equivalent of of 30 ppm on the surface. So a 20 ppm reading on the surface would be the equivalent 100 ppm at 132 feet depth (40 meters).


http://www.scubaboard.com/forums/ba...9-carbon-monoxide-tank-risks-protections.html


and


http://www.scubaboard.com/forums/co...5588-how-much-carbon-tank-no-good-130-ft.html
John

Frankly, you don't want any CO in your tanks if that is possible. It means that something is wrong with the filling process.

SeaRat