Testing Air Quality

[pescador775]

Here's the deal; oil vapor and volatiles like toluene (byproduct of overheated diester oil) carry a strong odor. Most divers can detect " bad" air. WRT the boogey man, carbon monoxide, a breathing gas laden with CO may carry an odor because CO is a product of combustion and is often entrained with smoke and particles. However, it is possible that a compressor could inhale or generate CO which is rendered odorless after passing through a filtration system. Thus, some divers may have an interest in CO detection equipment. Then, there is the oxygen clean issue. Generally, if the diver has normal sense of taste and smell it would be redundant to carry any instrumentation for contaminant detection unless the diver wishes to insure integrity of an oxygen clean tank. This is because the contaminant level which voids the O2 clean "warrantee" may be lower than the sensitivity of some divers' noses. However, assuming the contaminants being sampled have already been pumped into the tank this raises a problem for that situation. In any case, the diver's nose is the best judge of acceptable air for general diving use (except for CO). Therefore, if the diver is apprehensive about the quality of air when traveling or otherwise using questionable air sources it would appear to be sufficient to transport and use a portable CO monitor such as the Oxycheq product and depend on common senses for the rest. Beyond this I see no advantage in carrying scientific equipment for sampling and analysis, that is unless the diver is a salesman offering filter media and similar.

 

[Mad_Max]

I can see that having a portable unit that each diver carries around with themself may not be totally necessary or at least economically feasible. However, I'm surprised that filling stations don't have analyzers like this just as a matter of diligence. I guess I'm just naive, and assumed that all dive shops had this.
If you walked into Dive Shop A which had an instrument mounted to the wall, displaying O2 levels, CO levels, Humidity levels, CO2 levels, and total hydrocarbons as they filled your tanks, and then walked into Dive Shop B, which didn't; wouldn't you always bring your tanks to Dive Shop A?

I mean the technology for quantifying these concentrations in Air are all available, although it may not be economical for the average diver to own an analyzer like this, it might be practical for a dive shop? What if it were a couple thousand dollars?

 

[Hoosier]

Do you think that an average divers are talking about a compressor and air quality?

If some divers have already considered a humidity meter, CO, HE, and O2 analyzers, they aren't in the average group anymore.

rjack321 and pescador775 are all hard core on this matter.


Yes, I will bring my portable units to make sure.... Who know where you are diving?

 

[pescador775]

Divers spend more time in motor vehicles and in buildings than underwater. Motor cars generate a lot of carbon monoxide and volatiles like oil and gas fumes. I would think that a diver who was anxious about hazards of this type would first instrument their autos and perhaps, houses, then, lastly, worry about breathing air produced by commercial establishments (LDS). The usual approach to car safety, as well as compressors, is maintenance. The approach taken in homes varies but usually involves smoke and CO detectors as well as maintenance. Methinks, that is where the money is best spent, in the home.

 

[Thalassamania]

Divers spend more time in motor vehicles and in buildings than underwater. Motor cars generate a lot of carbon monoxide and volatiles like oil and gas fumes. I would think that a diver who was anxious about hazards of this type would first instrument their autos and perhaps, houses, then, lastly, worry about breathing air produced by commercial establishments (LDS). The usual approach to car safety, as well as compressors, is maintenance. The approach taken in homes varies but usually involves smoke and CO detectors as well as maintenance. Methinks, that is where the money is best spent, in the home.

If the air in the cabin of your car was at several atm or more then you might just.

 

[ageddiver]

Divers spend more time in motor vehicles and in buildings than underwater. Motor cars generate a lot of carbon monoxide and volatiles like oil and gas fumes. I would think that a diver who was anxious about hazards of this type would first instrument their autos and perhaps, houses, then, lastly, worry about breathing air produced by commercial establishments (LDS). The usual approach to car safety, as well as compressors, is maintenance. The approach taken in homes varies but usually involves smoke and CO detectors as well as maintenance. Methinks, that is where the money is best spent, in the home.

This really makes no sense. I don't worry about the O2 concentration in the air around my house, but I sure do when I'm at 250FSW. The exact same thing applies to all the "minor" contaminants in compressed air. Different story at depth.

 

[rjack321]

I bring my portable CO monitor to hot, steamy destinations where compressor maintenance is questionable. I also bring my 02 analyzer (nitrox, not because I think an air fill might be off). As bad as it might be, I am forced to rely on my nose for contaminants like toluene.

Others have ignored contaminants at their peril. Esp. in hot climates you are betting your life on gas quality.

 

[pescador775]

The potential for CO levels in gas heated homes and in autos is far higher than in Scuba tanks which generally contain less than 10 ppm. The levels found in some repair garages are routinely in the 60 ppm range. Freeway levels could approach that. Concentrations much higher can be found in idling cars with faulty exhaust systems. True, at a depth of 200 feet, the OSHA allowable range for CO in breathing air of 10 ppm can result in an effective fraction of 70 ppm but then the PP of oxygen is much higher too. Moreover, modern compressor filtration systems would rarely, if ever, emit 10 ppm. In any case, anybody so anxious about breathing air would do well to examine potential hazards closer to home. At least, in the pursuit of the mundane (but more common) hazards one would be consistent. If on a dive trip one also feels the need to carry a CO monitor in baggage, by all means do so. Personally, I am considering a catalytic converter for a cigar holder.

 

[cowjazz]

The potential for CO levels in gas heated homes and in autos is far higher than in Scuba tanks which generally contain less than 10 ppm. The levels found in some repair garages are routinely in the 60 ppm range. Freeway levels could approach that. Concentrations much higher can be found in idling cars with faulty exhaust systems. True, at a depth of 200 feet, the OSHA allowable range for CO in breathing air of 10 ppm can result in an effective fraction of 70 ppm but then the PP of oxygen is much higher too. Moreover, modern compressor filtration systems would rarely, if ever, emit 10 ppm. In any case, anybody so anxious about breathing air would do well to examine potential hazards closer to home. At least, in the pursuit of the mundane (but more common) hazards one would be consistent. If on a dive trip one also feels the need to carry a CO monitor in baggage, by all means do so. Personally, I am considering a catalytic converter for a cigar holder.

I once thought the same way.

Then I plucked body from the water, and watched another, very experienced diver perish; both victims of ridiculous levels levels of CO in their tanks.

Lesson learned. I bought a CO tester the day after I got home. I just look at as a useful tool in case another modern compressor system fails.

 

[pescador775]

I used to think the same way.

Then I plucked body from the water, and watched another, very experienced diver perish; both victims of ridiculous levels levels of CO in their tanks.

Lesson learned. I bought a CO tester the day after I got home. I just look at as a useful tool in case another modern compressor system fails.

Drunk driving is dangerous, too, but I don't carry a breathalizer with me.