Ronda Cross Tank CO Test cause of Death

[Tigerman]

Heres the scary part..
1900 ppm is the same as 0,19% and apparently diesel engine exhaus has less than 0,045% CO so even hooking the regulator DIRECTLY to the exhaust pipe of a diesel powered car - youd be less than 1900ppm.

To me that makes the whole reading sound BADLY flawed.
Yeah sure, petrol engine exhaust runs at 10-20k ppm but short of pumping the exhaust pretty much directly into the intake (which would be premeditated murder) I really dont see how its possible to get 1900ppm..

 

[Thalassamania]

I do believe that you can get 1900ppm from a compressor oil flash.

 

[Tigerman]

For long enough to fill the entire tank with 1900 ppm?

 

[Thalassamania]

It is no my area of expertise, just my recollection: yes, oil flash can result in 2,000 PPM CO.

In terms of the inlet, I remember a case, many years ago where there was a dive shop in the middle of a strip mall and someone pulled in with a semi and left it idling while the bank was being filled, not realizing that the truck's exhaust was right next to the compressor intake on the roof. No one died, but it was a rather bad scene.

 

[Dive-aholic]

Heres the scary part..
1900 ppm is the same as 0,19% and apparently diesel engine exhaus has less than 0,045% CO so even hooking the regulator DIRECTLY to the exhaust pipe of a diesel powered car - youd be less than 1900ppm.

To me that makes the whole reading sound BADLY flawed.
Yeah sure, petrol engine exhaust runs at 10-20k ppm but short of pumping the exhaust pretty much directly into the intake (which would be premeditated murder) I really dont see how its possible to get 1900ppm..

With the CO death I witnessed we unfortunately didn't have a CO analyzer and couldn't get one. However, autopsy did confirm cause of death was due to CO poisoning. Based on the depth and time into the dive when the symptoms first appeared I estimated 800 ppm CO in the tank. So high levels are possible. And it doesn't have to be premeditated murder. Just having someone park a vehicle without a properly functioning catalytic converter close to the compressor intake could be enough. I heard of a department sports store that had a scuba department and ATV department. Well, guess where they put the compressor? Out in the garage where they worked on the ATVs. Mechanics are out there revving up the ATV engines all day long while the compressor is filling the banks. This past summer I was picking up tanks at a fill station in Mexico and testing all the tanks as we loaded them. While we were doing this a minivan with bad exhaust pulled up about 25 feet away from me and my CO analyzer display jumped up quite a bit. A decent size compressor can fill an AL80 from 500 psi in about 5-8 minutes. Hook up 6 tanks and it's about 30 minutes. Delivery truck pulls up and delivery guy leaves the truck running while he unloads packages and gets signatures. This takes 15-20 minutes and in the mean time all that exhaust is pouring into the compressor intake.

Basically, what it comes down to is everyone should CO analyze every tank they dive no matter where the air is coming from. I have my own compressors and run them at specific times of the day and for a set amount of time. I send in specimens quarterly. I change my filters every 50 hours. I still test all the tanks that get filled from my banks. There's a way to prevent this and $300 is a small price to pay for peace of mind. Every shop should have one and should require all their customers to use it.

 

[DandyDon]

This is certainly interesting. I have no idea what the pictured document is exactly or what it says. A translation would be nice, along with an explanation of what it is exactly and how you can into posession of it. Sure, I'd be interested in Jorges and Roxanas tank results, with whatever info you can give.

The video is also quite interesting. I don't guess it proves anything as such a demonstration could be easily staged, but still - wow! The EII CO analyzer is rated to measure 1-50 ppm, but yes - I saw the demon of it going up past 1900?! The display is listed as 2 digit but mine shows 3 digits and perhaps it could read out 4?

Whatever all this does or does not actually illustrate, wherever the tanks were filled, or whatever - of course I strongly support testing each and every tank to be dived, regardless of how trustworthy a supplier may seem.

How the do you hit that level of CO in a tank... remove all filters from the compressor and then back a truck up to the intake?

I get antsy if my CO analyzer doesn't stay at 000 when I check a tank, though I recently dived one that blew a 001 and noticed no ill effect. I would have demanded another if it was 002 or higher.

I can't imagine any vehicle producing that rate of CO. Sure, a vehicle can put out enough to kill, hardly a month goes by without CO deaths in the US attributed to vehicle exhausts - accidents, suicides, even murders - but I can't imagine any vehicle producing that rate, much less that rate at compressor inlet. I think small engines like lawn mowers, chain saws, generators (all too common source in power outages leading to deaths) are worse, but those numbers are too much for any engine I think.

BTW, a 1ppm reading is nothing to be concerned about IMO, all too easily attributable to operator handling and/or rounding of results. Even a 2 ppm could be an error, but 3 ppm would be a reasonable rejection point - and some countries do have regulations limiting tank air to no more than 3 ppm.

I do believe that you can get 1900ppm from a compressor oil flash.

That sounds more likely.

 

[t-mac]

The video is also quite interesting. I don't guess it proves anything as such a demonstration could be easily staged, but still - wow! The EII CO analyzer is rated to measure 1-50 ppm, but yes - I saw the .

Just a little perspective on this point. If the analyzer is rated at 1-50, a reading of 1900 means nothing more than it is above 50. It is not reliable beyond that and the true reading could be much lower (or much higher) than 1900. Obviously, no matter what the real reading is, it is a lot. But in terms of the plausibility of getting that much CO into a tank, this reading should be viewed suspiciously. The only thing we can conclude is that it is somewhere above 50. It is probably substantially higher, but does that mean it is 100, 1000, 2000? We just don't know and the reason instruments are rated is to let us know the range in which they can reliably be operated. It is a mistake to attach any precision to a reading that is out of range - especially so far.

 

[tech_diver]

Another point…
Isn’t the OP setting himself up for potential lawsuits?
By posting this information without substantial documentation of its authenticity, couldn’t someone claim they were defamed by these postings?
Even if the OP genuinely believed the video was real, doesn’t he run the risk of being sued just by publishing it? Does SB run that risk by hosting it?
I think some of us can remember a similar case.

 

[nimoh]

From what I have read in this thread, 1900 ppm sounds very unlikely (accidentally anyway), and there seems to be a lot of smoke and mirrors around how the tank was made available for testing.

However, without sidetracking the discussion too much, can anyone explain what a compressor oil flash is? (just curious)

 

[DivemasterDennis]

Threads like this led me to purchase my first CO analyzer about a year ago. Everyone should have one.
DivemasterDennis