Fatality Cabo San Lucas March 3

[bleeb]

3ppm=0.000003%

Uh, are you sure? I thought 3 ppm = 0.000 003x = 0.000 3%. Granted, I'm a little tired right now and the organic dive computer ain't working all that well.

 

[DandyDon]

3ppm=0.000003%

3% = 3/100

3 ppm = 3/1,000,000 = 0.000003 = 0.0003% = pesky decimals.

 

[dmoore19]

Uh, are you sure? I thought 3 ppm = 0.000 003x = 0.000 3%. Granted, I'm a little tired right now and the organic dive computer ain't working all that well.

10,000 ppm would be 1%

3 parts per million= 0.0003%

3/1,000,000=.000003

You are correct, sorry my organic calculator slipped a cog.

At any rate, over all it just shows CO can be very deadly in extremely low concentrations. 3 ppm is not much, but it might be enough to kill at depth.

 

[dmoore19]

3% = 3/100

3 ppm = 3/1,000,000 = 0.000003 = 0.0003% = pesky decimals.

Yes Don, you too are correct. 3% is .03. Now that I have been beaten into submission I will keep quiet.

 

[DandyDon]

At any rate, over all it just shows CO can be very deadly in extremely low concentrations. 3 ppm is not much, but it might be enough to kill at depth.

Well, 10 ppm is the US standard max, and mine. Both are tiny amounts, urban environments often run around 5, and 10-15 ain't much at 1 atmosphere - but taken to 3, 4, 5 it gets multiplied. There's much more to that, too.

3 ppm is when I start complaining.

 

[dmoore19]

carbon-monoxide-poisoning.com/article1-co-levels.html


At what level does carbon monoxide become toxic?
For healthy adults CO becomes toxic when it reaches a level higher than 35 ppm (parts per million) with continuous exposure over an eight hour period.. When the level of CO becomes higher than that a person will suffer from symptoms of exposure. Mild exposure over 2-3 hours (a CO level between 35 ppm and 200 ppm) will produce flu-like symptoms such as headaches, sore eyes and a runny nose. Medium exposure (a CO level between 200 ppm to 800 ppm) will produce dizziness, drowsiness and vomiting in as little as 1 hour. This level of exposure is deemed to be life threatening once three hours has passed. Extreme exposure (a CO level of 800 ppm and higher) will result in unconsciousness, brain damage and death in as little as a few minutes. OSHA guidelines state that the maximum exposure over an eight hour time period is 35 ppm.

 

[Ayisha]

Remember that those figures are not at depth. The effects of CO are pronounced at depth and it takes a lot less than 35 PPM to begin to have symptoms. I believe there was some info posted at some point about what level of CO becomes toxic at increasing atmospheres and for longer periods.

 

[daniel1948]

3 ppm is not much, but it might be enough to kill at depth.

I was under the impression, from the above, that 3 ppm was considered safe under the most conservative (UK) standard. In which case there should be little chance of ill effects with 3 ppm in recreational diving.

 

[DandyDon]

We seem to have a bit of confusion maybe, as it can go that way..

carbon-monoxide-poisoning.com/article1-co-levels.html


At what level does carbon monoxide become toxic?
For healthy adults CO becomes toxic when it reaches a level higher than 35 ppm (parts per million) with continuous exposure over an eight hour period.. When the level of CO becomes higher than that a person will suffer from symptoms of exposure. Mild exposure over 2-3 hours (a CO level between 35 ppm and 200 ppm) will produce flu-like symptoms such as headaches, sore eyes and a runny nose. Medium exposure (a CO level between 200 ppm to 800 ppm) will produce dizziness, drowsiness and vomiting in as little as 1 hour. This level of exposure is deemed to be life threatening once three hours has passed. Extreme exposure (a CO level of 800 ppm and higher) will result in unconsciousness, brain damage and death in as little as a few minutes. OSHA guidelines state that the maximum exposure over an eight hour time period is 35 ppm.

I think this might be a better list? Risks of Carbon Monoxide poisoning

Remember that those figures are not at depth. The effects of CO are pronounced at depth and it takes a lot less than 35 PPM to begin to have symptoms. I believe there was some info posted at some point about what level of CO becomes toxic at increasing atmospheres and for longer periods.

Yes, 10-15 ppm can be like 50-75 ppm around 140-150 ft, but there is a lot more to that - so we want CO lower even for shallower dives.

I was under the impression, from the above, that 3 ppm was considered safe under the most conservative (UK) standard. In which case there should be little chance of ill effects with 3 ppm in recreational diving.

Well, 10 ppm is the US standard max, and mine. Both are tiny amounts, urban environments often run around 5, and 10-15 ain't much at 1 atmosphere - but taken to 3, 4, 5 it gets multiplied. There's much more to that, too.

3 ppm is when I start complaining.

 

[Dive-aholic]

3ppm is the maximum allowed for oxygen safe air, meaning air that can be used to partial pressure blend with 100% oxygen. 10ppm is the maximum allowed for grade E scuba air. Personally, I'll give it 1ppm because I've seen the analyzer go back and forth between 0 and 1 just holding it in ambient air. It takes actual CO to bring it up to 2. And if there's any CO in the cylinder then there are problems with the fill station and I don't want to dive a cylinder that has even just 2ppm. If there's CO in there, what else is there that we're not testing for?