CO Analysers

[RayfromTX]

It might be very bad news. Oxtox occurs at different concentrations and durations for different people. The limits are set based on keeping almost everyone safe. Many people violate their mod, sometimes badly without a negative outcome but the result of a bad outcome is almost always very bad so we don't push it. The mod limit recommendation used to be 1.6ppo. It wasn't changed because everyone was dying and is still used for deco but if everyone went back to 1.6 there would be more negative outcomes and that's not a game we wish to play.

 

[Hojo in SC]

Will an oxygen analyzer pick up CO level, I'm thinking no, it would just show how much oxygen is in the tank.

 

[DandyDon]

Will an oxygen analyzer pick up CO level, I'm thinking no, it would just show how much oxygen is in the tank.

Correct, nope.

 

[Scuba-Lad]

Gap in the market it seems (no CO and O2 combo tester available) and huuuge risk being taken by a lot of divers by not testing in this part of the world. I've ordered a separate CO tester, pretty much the only one available here:

 

[DandyDon]

I've ordered a separate CO tester, pretty much the only one available here:

Do let us know how it works for you. I'd suggest a report thread in Computers, Gauges, Watches & Analyzers

 

[Hatul]

Gap in the market it seems (no CO and O2 combo tester available) and huuuge risk being taken by a lot of divers by not testing in this part of the world. I've ordered a separate CO tester, pretty much the only one available here:
View attachment 665298

The accuracy listed may not be good enough for Scuba where you want the CO to be less than 4 ppm or so. Let's say the true CO concentration of tank is 8 PPM, which is too high to use, your meter may read 0 PPM, since the accuracy is +- 10.

 

[DandyDon]

The accuracy listed may not be good enough for Scuba where you want the CO to be less than 4 ppm or so. Let's say the true CO concentration of tank is 8 PPM, which is too high to use, your meter may read 0 PPM, since the accuracy is +- 10.

A max of 4 ppm is an admirable goal but not very realistic. If your readings are 0 really meaning 10 or a reading of 4 really meaning somewhere between 0 & 14, they will still protect you enough for most diving if the unit works as claimed. I don't know anything about that brand, but if it's the only unit available in the country, you just have to accept that you did your best.

 

[Hatul]

A max of 4 ppm is an admirable goal but not very realistic. If your readings are 0 really meaning 10 or a reading of 4 really meaning somewhere between 0 & 14, they will still protect you enough for most diving if the unit works as claimed. I don't know anything about that brand, but if it's the only unit available in the country, you just have to accept that you did your best.

The Sensorcon accuracy is listed as 10% without an absolute value, which for our low values of 10 PPM or lower, is much better, as that translates to +- 1PPM.

 

[DandyDon]

The Sensorcon accuracy is listed as 10% without an absolute value, which for our low values of 10 PPM or lower, is much better, as that translates to +- 1PPM.

Great units. I ran one thru a complete washing machine cycle once with no harm. But he is in Indonesia.

I've ordered a separate CO tester, pretty much the only one available here:

 

[Hatul]

A max of 4 ppm is an admirable goal but not very realistic. If your readings are 0 really meaning 10 or a reading of 4 really meaning somewhere between 0 & 14, they will still protect you enough for most diving if the unit works as claimed. I don't know anything about that brand, but if it's the only unit available in the country, you just have to accept that you did your best.

I know the acceptable CO level of tank air has been discussed on Scubaboard but the article from DAN of last year
Carbon Monoxide Safety - Divers Alert Network
recommends a 5 PPM as the acceptable standard as any higher likely indicates a problem with the compressor or contamination. It really should be 0 or close to that, and when I test my tank air here in California it has always read 0.
Aside from the increase in partial pressure at depth, when we're diving we're exposed to stresses such as CO2 retention, hyperoxia and nitrogen narcosis, so the effects of CO in the gas may have a synergistic effect with those, somethings that may not have been taken into account in studies on land. Also it may go along with other contaminants from the compressor such as hydrocarbons from burnt oil or intake gas.