Bad air originating in tank and not compressor

[Doc Harry]

It's been awhile since I've used my chemistry degree, but a paper from 1978 is dated.

Please let me know the chemical reaction to take Iron Oxide to CO.
It takes a lot of energy to break CO2 to CO, and I don't see anything in a rust lined tank producing that much CO. C02 would be the only available Carbon in an air filled tank, with the exception of trace C0. I think it is instrument error or there was contamination from compressor air already present. . It reminds me of the paper on Cold Fusion.

Dated or not - there hasn't been any such research since then, so it's still best data available.

I agree that 70-80 ppm sounds high for corrosion-related CO. The studies from 1978 showed that corrosion could increase CO in the range of 15 ppm. That's quite different from 70 ppm.

My vote is that the compressor burped some CO in conjunction with a corroded tank.

 

[vincent54]

Dated or not - there hasn't been any such research since then, so it's still best data available.

I agree that 70-80 ppm sounds high for corrosion-related CO. The studies from 1978 showed that corrosion could increase CO in the range of 15 ppm. That's quite different from 70 ppm.

My vote is that the compressor burped some CO in conjunction with a corroded tank.

Whatever the cause it was good to check and not use the tank. I think it would be a good research project for an up and coming college student, especially one interested in diving. Cheers

 

[grf88]

Whatever the cause it was good to check and not use the tank. I think it would be a good research project for an up and coming college student, especially one interested in diving. Cheers

I was thinking of doing it myself with a tank that had failed hydro but then I realized that there was a good reason why they stored the test tanks in a bunker.

 

[Komi]

.. I plan on contacting Analox to see if there is anything else to explain what might have happened and if it is possible that the sensor is sensitive to any other compounds..

Please do let us know what they say. Very interesting!

 

[vincent54]

I was thinking of doing it myself with a tank that had failed hydro but then I realized that there was a good reason why they stored the test tanks in a bunker.

I have a couple of old steel tanks to donate if you need test samples. Keep us posted.

 

[Johnoly]

.... It was not so much as what was said but the "listen stupid, it came from the compressor" tone that was presented......

The laws of physics will never change on CO. I think you did a great job of bringing awareness to all the readers how important it is to test every scuba tank you use. With over 2000 views you have hopefully saved several more diver's lives because they now test due to reading your story.

 

[swamp diver]

Corrosion studies of steel scuba cylinders performed by the University of Rhode Island revealed that severe corrosion could produce elevated levels of CO just from oxidation of the steel.

InRhode

The full study can be read here thanks to the Rubicon Foundation which always is in need of further donations.
Investigation of scuba cylinder corrosion, Phase 1.

---------- Post added August 20th, 2014 at 10:36 AM ----------

May be a popular bump test but it's not a good one. Your body does not produce CO. Any CO that comes out is just stuff offgassing because you breathed it in. That's why smokers have a higher level of CO than non-smokers.

Not true at all. The human body now has three 'gasotransmitters' identified which are produced by endogenous biochemical pathways. We make nitric oxide (look up how Viagra works), hydrogen sulfide, and carbon monoxide in very low concentrations. These gaseous transmitters allow the fastest cell to cell communication, much faster than say hormone messaging.

Last time I checked carbon monoxide was possibly involved in the body's control systems for blood pressure and oxygen sensing. If you breathe in a bunch of CO from an external source you are going to disrupt these critical physiological control systems.
http://www.google.ca/url?sa=t&rct=j...NDUnp8P7eO1k6cg&bvm=bv.73231344,d.aWw&cad=rja

 

[abnfrog]

the simplest thing i find with mechanical devices is usually the right one ...piston rings sometimes stick (do not seat ) oil might have been just changed (overfilled or the wrong one) we all know compressing gas in a compressor with oil ,has the possibility to diesel ........the rest is all GUESSING..............moral ALWAYS ALWAYS test your gas ..........................nuff said

 

[Patti Analox]

Dear Divers,

"Holy Smokes" (all puns are intended). What a read! I'm not going to speculate as to what created the high CO in GRF88's rusty tank. At the end of the day, the CO was present and was detected and his son is safe. I'm VERY happy GRF88 took the time to detail this story as CO in diving remains a threat. I don't have to tell you, you guys (informed, willing to share your knowledge, engage in discussion and educate others) are a very VERY tiny fraction of divers in the world. CO awareness STILL does not enter the mind of the vast majority of scuba divers. You guys are saving lives simply by engaging in these valuable discussions.

This being said I have the unpleasant duty to inform all of you that as of 23rd July 2014, Analox will no longer be manufacturing the EII CO. Analox are planning a campaign to work with filling stations and compressor companies to ensure either the CO Clear or ACG+ analysers are fitted and used to monitor breathing air at the compressor stage. Analox will still be supplying EII CO spares until July 2016.

Now before you give me both barrels, please know Analox is very much committed to diver safety and will continue to educate the diving public regarding the dangers of CO in diving. We will aggressively promote the fitting of CO compressor monitors. As GRF88's story shows, tank monitoring will indeed still be necessary and there are many products still on the market to do so.

Safe Diving,
Patti

 

[flots am]

Analox will no longer be manufacturing the EII CO. Analox are planning a campaign to work with filling stations and compressor companies to ensure either the CO Clear or ACG+ analysers are fitted and used to monitor breathing air at the compressor stage.

That's too bad, because there isn't a snowball's chance in hell that the places that need monitoring will buy the equipment, and even if they do, there's no reason for divers to trust them any more than they trust the O2 percentage in nitros.

In any case, AFAIK, KWJ Engineering still senss the pocket CO, although it's not as easy to use as yours.