Thread Split - Unable to breathe

[MXGratefulDiver]

Nobody likes to believe that their class sucked ... least of all, the instructor ...

... Bob (Grateful Diver)

 

[bleeb]

To expand on Bob's post some more, and because it seems to be an uncomfortably frequent area of confusion even among trained divers:

CO (carbon monoxide) is the stuff that also comes out car exhaust tailpipes and gas fired heaters that kills people. For divers, 10-20 ppm (parts per million, i.e. 0.001-0.002%) is enough to cause serious problems. The average carbon monoxide detector you have at home typically go off somewhere around 75-250 ppm. On the surface, it's less of an issue because you are breathing it under pressure. Carbon monoxide is what's been blamed for the recent death in Cozumel the OP was referring to. CO can get into your tank by sucking in car exhaust, exhaust leaking internally in a gas-powered compressor, a poorly maintained compressor whether gas-powered or not, or a compressor which is simply running too hot.

CO2 (carbon dioxide) is the stuff you breathe out. As long as there is enough O2 (oxygen) in the air, carbon dioxide won't kill you until it makes up something approach 10-15% of your breathing gas, although most people will be feeling uncomfortable by 5%. Normal air contains less than 0.1% CO2 before you breathe it. It's also a product of combustion, and in theory could get into a tank from a gas-powered compressor, but if that's happening, much more lethal stuff like CO and soot is getting in there, so I don't think anyone ever worries about CO2 getting added to the tank.

When you test a tank of Nitrox, you are not testing for CO or CO2. All you're doing is checking that there isn't too much O2.

 

[DandyDon]

I see that this is a split-off, but not sure what the focus is here...?

A better approach is to have a community that understands norms of behavior and polices itself by both adhering to those norms and by reminding others of them as necessary. Although I do encourage people to hit the report button, a better approach is for people to make posts reminding the offender that such behavior is not within the norms of the forum.

Nice idea, but sometimes I get accused of attempted to Mod, even worse. I am safer Reporting and need to do so more, shoot my mouth less.

 

[boulderjohn]

I see that this is a split-off, but not sure what the focus is here...?

Nice idea, but sometimes I get accused of attempted to Mod, even worse. I am safer Reporting and need to do so more, shoot my mouth less.

This was clear in the context before the split. I think it was put in the wrong one after the split.

 

[stevensamler]

Wow , get someone a box of tissues and a hug!