2airishuman
Contributor
Dive shops around here tend to send air to the lab more or less once a year. Some shops do a certain amount of fudging to make the test dates line up with their scheduled compressor maintenance.
I guess that once upon a time quarterly tests were the gold standard. Even then, there's a lot of air that gets pumped in between tests.
So, some questions.
1) When tests results show that air does not meet standards, what is the usual cause? Moisture, CO, hc?
2) What are the typical real-world root causes of the problems these tests actually catch? e.g. compressor overheating, undersized filtration towers, operator not draining moisture separators, problems with input air, internal compressor failures, etc?
3) Does an annual or even quarterly test provide enough advance warning to deal with problems before they pose a hazard to divers or a corrosion hazard to equipment? Or does it only tell you what went wrong after people are injured and a pallet of cylinders are ready for the tumbler?
4) Is continuous surveillance a better alternative to lab tests? If you test every fill for CO and test your CO analyzer with bump gas, why pay to send a sample to the lab? Do the moisture eye/CO eye cards (that change color when contaminants are present and can be placed in a high-pressure housing) provide a reasonable level of surveillance either alone or in combination with an electronic CO tester?
5) Are particular settings more and less prone to problems e.g. liveaboards, dive shops, fire houses, personally owned compressors, tropics, frozen north?
6) Is this still a valuable tool or is it a holdover from an era when people were using surplus flamethrower compressors and filtering the output through crushed drywall chunks and activated charcoal from the aquarium store?
I guess that once upon a time quarterly tests were the gold standard. Even then, there's a lot of air that gets pumped in between tests.
So, some questions.
1) When tests results show that air does not meet standards, what is the usual cause? Moisture, CO, hc?
2) What are the typical real-world root causes of the problems these tests actually catch? e.g. compressor overheating, undersized filtration towers, operator not draining moisture separators, problems with input air, internal compressor failures, etc?
3) Does an annual or even quarterly test provide enough advance warning to deal with problems before they pose a hazard to divers or a corrosion hazard to equipment? Or does it only tell you what went wrong after people are injured and a pallet of cylinders are ready for the tumbler?
4) Is continuous surveillance a better alternative to lab tests? If you test every fill for CO and test your CO analyzer with bump gas, why pay to send a sample to the lab? Do the moisture eye/CO eye cards (that change color when contaminants are present and can be placed in a high-pressure housing) provide a reasonable level of surveillance either alone or in combination with an electronic CO tester?
5) Are particular settings more and less prone to problems e.g. liveaboards, dive shops, fire houses, personally owned compressors, tropics, frozen north?
6) Is this still a valuable tool or is it a holdover from an era when people were using surplus flamethrower compressors and filtering the output through crushed drywall chunks and activated charcoal from the aquarium store?
