Ronda Cross Tank CO Test cause of Death

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For instance, let take the quarterly testing (with a bit of a divergence). A good idea in concept but difficult in practice as it is a snap shot at that time but says nothing about the current conditions (just a cylinder VIP). BITD that was really about the only mechanisms most facilities had. And if in easily accessible area having samples tested is simpler than in a remote area which is often the case with the best diving. So if it takes weeks to send off and get the test results does that really help? Now this does not even take into account when the samples are taken, before, after, or between scheduled maintenance. As such, I can see why PADI dropped it as programmatically there are some issues.

The air quality test is simple to perform, right at the fillers shop using a portable test kit (CO2, CO, Oil Mist, & Moisture). The basic process is to fill a cleaned empty cylinder, then analyze the gas with a series of indicating test tubes. The whole test takes about 40 minutes (oil mist is a 25 minute collection). It is just a snapshot, but combined with appropriate compressor maintenance, it provides the filler with a level of confidence that his system is operating nominally. It also can provide the filler data to indicate he needs a higher order service call.

PADI is just not interested in sharing any liability on air quality. So, I agree with the prior posts - vote with your wallet. I drive an extra 25 minutes each way to use a LDS that has a compressor maintenance contract and tests their air. I also have told my new LDS why I left the old one. Positive feedback for the extra effort a LDS takes to provide a good product promotes continued high performance when other business stressors enter the cost benefit decision matrix.
 
You should move to Canada where any compressor used for fire service or commercial diving must have a high air temperature (HAT) alarm and low oil pressure (LOP) alarm. All compressors used for breathing air applications should have both and the manufacturers like Bauer, Nuvair, etc. can supply you with one.

All the Bauer compressors above a certain size come with the final stage head already drilled out for a temperature sensor or bimetal switch. The Bauer B-trox nitrox compressor comes with a HAT alarm on all four stages. You can retrofit a compressor with one if you have a PLC that can be modified to accept another input.

Upon checking your US fire service compressed breathing air standard NFPA 1989 they also require all fire service compressors to have a HAT and LOP alarm. Walk in to your local fire hall and ask them to show you the HAT alarm. Here are the NFPA 1989 clauses:

7.2.2 Oil-lubricated compressors shall be equipped with a
tamperproof, audible, high temperature alarm that shall shut
down the compressor at the temperature specified by the compressor
manufacturer.

7.2.3 Oil-lubricated compressors shall be equipped with a
tamperproof low oil level, low oil pressure, or both low oil level
and low oil pressure audible and visual alarm that shall shut
down the compressor if the oil level or the oil pressure drops
below the limit specified by the compressor manufacturer.

The reason that there is such a high failure rate for CO contamination in dive air (~ 3 percent of samples submitted) vs. the fire industry (~ 0.1%) is we have no oversight whatsoever of compressor installs, operation, maintenance, etc. Until that happens which I doubt it will in places like Mexico, Egypt, or the Maldives the only solution is for every diver to check each and every tank for CO contamination before use.

Fire halls in Canada and the USA have up to date well-maintained compressors and usually the operators whose colleagues also breathe the same air are trained in safe air production. Typical dive shop compressor in Mexico is an old ratty compressor with little to no preventative maintenance and certainly no regular air testing or CO monitoring. The operators learned how to run the compressor from the previous owner who learned from the previous owner. Bad habits are passed along.

If you want to read how compressed breathing air should be produced and monitored I'd recommend you purchase the new NFPA 1989 standard for only $35 and follow their recommendations for quality assurance.
NFPA 1989: Standard on Breathing Air Quality for Emergency Services Respiratory Protection

PADI pulled out of overseeing their affiliates air testing programs four years ago for liability reasons. I wouldn't be surprised to see their entire affiliate program go by the wayside with a few more court cases and settlements against them in this area. The elephant is out of the room.

Great info! Thanks for posting it. I bought a compressor from a fire department last year that I plan on rebuilding. I'll have to see if it has a HAT installed. I looked it over briefly when I bought it (really good deal so I didn't look too hard) but I don't remember seeing anything that I haven't seen on the other compressors I own.
 
The air quality test is simple to perform, right at the fillers shop using a portable test kit (CO2, CO, Oil Mist, & Moisture). The basic process is to fill a cleaned empty cylinder, then analyze the gas with a series of indicating test tubes. The whole test takes about 40 minutes (oil mist is a 25 minute collection). It is just a snapshot, but combined with appropriate compressor maintenance, it provides the filler with a level of confidence that his system is operating nominally. It also can provide the filler data to indicate he needs a higher order service call.


Good info as I had thought that test samples had to be sent in for analysis. Can you give some pointers to the field testing kits that are available.
 
Good info as I had thought that test samples had to be sent in for analysis. Can you give some pointers to the field testing kits that are available.

That is how we used to do it in Canada and the USA back about twenty to twenty five years ago. Many outfits still use the Draeger HP Simultan kit for fill-in testing. We still use the moisture tube alone to check dew point on the spot during the winter to reduce free flow risk. There are problems with the kit which are outside the discussion of this thread, but one of the major ones is that there is no general tube for volatile hydrocarbons which is one reason the fire service and dive industries went to lab testing.

I think there is a similar kit for HP air from Sensidyne but I have found the tubes from Drager to be of higher quality and easier to read.
Compressed Air Testing using the Aerotest HP (High Pressure) System by Draeger Safety

Cost for the Drager kit $4000 plus consumables. :shocked2:
 
Good info as I had thought that test samples had to be sent in for analysis. Can you give some pointers to the field testing kits that are available.

We're using an Air Care Breathing Air Purity Test Kit using kitigawa tubes. The kit comes with an analyte specific adjustable flow regulator. Cost is about $1000, plus consumables.
 
We're using an Air Care Breathing Air Purity Test Kit using kitigawa tubes. The kit comes with an analyte specific adjustable flow regulator. Cost is about $1000, plus consumables.

I forgot about that kit which is put together by UnderSea Ltd. in the UK. We have one here that we tested and while not bad for CO, CO2 and oil the Kitigawa moisture tubes had poor accuracy. You can see the kit on page 29 of the catalogue here.
Undersea Ltd - Serving the diving industry since 1970

 


A ScubaBoard Staff Message...

In post #79 in this thread, another mod made it perfectly clear that the A&I forum is not the place for a one-sided war between dive shops. The warning was that any more such posts would be deleted, and that is what has happened. It will happen again with any more such posts that appear.
 
Hi, so are these CO checkers easy to use? also how much would one have to spend on the CO checker for personal use only?
Thankyou.
 
Maybe johnZdiver can chime in and give us some information on them?
 
Hi, so are these CO checkers easy to use? also how much would one have to spend on the CO checker for personal use only?
Thankyou.
Very easy. About the same as the Analox Nitrox analyzer. They cost over $300, and the sensor needs to be replaced after a few years, but it's the only way to be sure. You can rent one for a week at Outdoor Equipment Rentals - see my sig.
 
https://www.shearwater.com/products/perdix-ai/

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