Testing for Carbon Monoxide May Save You

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RayfromTX

Student Of Gas Mixology
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I was on a liveaboard in the Gulf of Oman last weekend. I always test for CO with my cootwo. I have found numbers as high as 2ppm but usually somewhere in the .3 to .9 range if any is detected. On this boat there were tanks from two different suppliers and there were about 60 tanks on board as they didn't have an onboard compressor. On the third tank I found 5 ppm so I kept checking.

I grabbed the organizer of the trip and he jumped into action. We tested every tank on board. about 20 tanks ranged from 5ppm to 7ppm. Two of the tanks jumped up to 25ppm and started flashing a TOO HIGH! message and didn't give readings again until the unit was flushed out with clean air for a while. I suspect the readings would have been higher than 25 ppm but the unit seems to top out and goes into an alert mode above that level.

We dove the tanks that read less than 5ppm and I only dove the tanks that read under 3 ppm and for deeper dives only dove those that read less than 2 ppm.

I have had people on boats tell me that they don't need to test their tanks because mine read fine so theirs will be too but I know better. Compressors can put out one bad tank in a string of acceptable ones or can put out good ones until it starts to run hot or the filter gets overloaded or the truck pulls up near the intake and sits idling while loading or unloading. TEST ALL TANKS!

@DandyDon Thank you for alerting us to the danger and the need to test all tanks. I'm pretty sure you and your crusade saved someone from getting very sick this last weekend on the other side of the world. They would have never known why they got sick because the other people on the boat were fine......
 
I have had people on boats tell me that they don't need to test their tanks because mine read fine so theirs will be too but I know better.
Yep, too much of that even when we try to show the need. Good on you for testing every tan and preventing injuries.

Compressors can put out one bad tank in a string of acceptable ones or can put out good ones until it starts to run hot or the filter gets overloaded or the truck pulls up near the intake and sits idling while loading or unloading. TEST ALL TANKS!
Yep, Russian Roulette with an estimated 3% risk is still dangerous.

Yes!

...As someone who has had two suspected CO hits, it's not an experience to repeat.

Hmmm, wonder if I should invest in an analyzer....
Cameron
I guess you were joking, but we actually heard from a couple who survived the infamous Maldives CO tragedy years back. As sick as they got, and even witnesses death from the toxic tanks, he still was diving without a CO tester. His wife quit diving with him tho, last I heard.
 
Yep, too much of that even when we try to show the need. Good on you for testing every tan and preventing injuries.


Yep, Russian Roulette with an estimated 3% risk is still dangerous.


I guess you were joking, but we actually heard from a couple who survived the infamous Maldives CO tragedy years back. As sick as they got, and even witnesses death from the toxic tanks, he still was diving without a CO tester. His wife quit diving with him tho, last I heard.

Unfortunately serious. I now only do my own fills or use a "trusted" source. Haven't adopted analyzing every tank yet.
 
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I don't even trust myself. I am using a rix with a lawrence factor filter and I still test every tank. You saw me test tanks when we dove together. It will have to be something else that gets me because this one is preventable.
 
@DandyDon

What brand/model CO detector are you currently using?

If you were to buy new today would you buy the same or different model?

Thanks
 
@DandyDon

What brand/model CO detector are you currently using?

If you were to buy new today would you buy the same or different model?

Thanks
I have an Analox, a Sensorcon, and a Cootwo. I'm a bit of a fanatic; my way of putting action to my words. Experts are difficult to find, DAN still does so little, so I try to learn as much as I can.

The Analox model is no longer made and replacement sensors are expensive, so it's going away. The Cootwo is the best on the market I think, testing O2 and for CO - and I have seen divers go down on Nitrox by mistake - but for those who don't want to spend that much, the Sensorcon can certainly suffice. I leave my Sensorcon on 24/7 to protect against vehicle risks and hotel rooms.
 
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It will have to be something else that gets me because this one is preventable.
Unless you are using a defective analyzer. You should be using two different brand analyzers.
 
https://www.shearwater.com/products/swift/

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