CO - how high will you go?

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Different safety agencies in the us have established safe levels. The LOWEST level set is 25 ppm for exposure 40 hours per week. So When I check tanks for CO ppm, i stick to single digits only. Checking my log, I have actually never dove with higher than 3 ppm, and that just once. Average household indoors wif you have no gas stove or oven is 0.5 to 5 ppm. If you have a gas stove or oven, then 5 to 15 ppm.
DivemasterDennis
 
What exactly is this and how do you test for it and why is it important?

Well the start of the diving holiday has been interesting. I discovered on my first tank that my analyzer does in fact read above 001 when I got a read of 15ppm on the first tank I tested. Immediately rejecting it, I managed to find two tanks that were down around 7ppm. As the dive was only a first checkout dive to 5m I took them, but was not happy. Stern words with the owner resulted in him extending the snorkel on the compressor input another 5m higher.

Now after the change, the tanks are reading 5ppm. But still, I've never seen a tank over 1 before, and can't help but feel that there is still something wrong with his filter setup.

It's a petrol compressor, but I still feel that the hopcalite should be brining it close to zero.

Am I just being paranoid? Where exactly should I stop worrying about it? Is anything under 10ppm going to be insignificant for rec dives below 30m? What should my ppm per atm cutoff actually be?

Sent from my iPad using Tapatalk HD
 
What exactly is this and how do you test for it and why is it important?

It is carbon monoxide, you test for it with a CO analyzer and it's important because if you breath enough if it you will die.
 
What exactly is this and how do you test for it and why is it important?

Carbon Monoxide binds to the haemoglobin inhibiting the Oxygen molecules from binding. CO binds more readily to the haemoglobin than O2 does. As you increase the partial pressure of CO (as you go deeper) this gets more significant. Essentially your blood carries lower oxygen levels, until it reaches fatally low levels.
This is a simplistic explanation and Dandy Dons article is far more in depth.
 
Carbon Monoxide binds to the haemoglobin inhibiting the Oxygen molecules from binding. CO binds more readily to the haemoglobin than O2 does. As you increase the partial pressure of CO (as you go deeper) this gets more significant. Essentially your blood carries lower oxygen levels, until it reaches fatally low levels.
This is a simplistic explanation and Dandy Dons article is far more in depth.
There have been cases of one from the boat dying with the rest only injured, or others of the whole boat ill from CO - and even if you survive, severe neurological problems can linger. Or it might be one extreme tank out of a lot filled around the same time. Too many unknown possibilities without testing. I certainly did not want to spend that much on a CO tester, but it was worth it. :wink:
 
Has there been any studies completed on how the CO Levels change at different depths. Don do you use the Bump Test Gas before you use your analyser.
 
Has there been any studies completed on how the CO Levels change at different depths. Don do you use the Bump Test Gas before you use your analyser.
I don't remember any such studies, and it's be difficult to run any that would harm participants. The increase in partial pressure is the increased risk.

I just blow in mine. All breath has a little CO.
 

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