This still going? Ok...
As I tried to say before, and was misunderstood by some, or I might not have stated it clearly - I'm not going back in a diligent search to establish which as it's more depends on reader's view I think: No one knows how often that cases of traveler's illness were really cases of subclinical CO hits, nor how many of the lost or drowned divers were really incapacitated by tank CO? You can pick any number between
none and
all and your guess is as good as any - for the island, the area, etc. The risks have simply not been well studied, some are just not aware, and some who are still don't want to. Besides, it'd be pretty hard to do such studies as the common practice for suspected tanks is to drain them, not publicize such. Even for compressors running inline monitors now, if they are monitored & maintained well, I doubt the owners are going to be interested in reporting their bad experiences.
I'll just add that if I were a cave diver, diving in conditions in which calling a dive and heading for the surface were not an option, I would rigorously analyze every aspect of my air, including CO content.
Well, I had thought the the cave diving community would be more likely already testing for tank CO simply because of their technical nature & approach to diving, but I learned that was not the case. They were generally as far behind as most of us on this, altho seemingly more interested in changing. I spent some time on one of their forums after a cave death on Coz and that was my impression anyway. That one was previously blamed on CO, more recently other factors have been made known to me, but the team agreed that that they just did not want to discuss the details in public.
Heading for the surface works well for LOA/OOA situations, but not so well for CO hits in part because of the way CO binds with blood and stays as previously explained. It didn't work for the 2 who died in Roatan a few years back, not for the Maldives bunch who were all very ill surfacing - 1 dying, not in the more recent Baja accident with 2 ill & 1 dead. It's worth a try and sometimes makes the difference so a cave diver would seem more at risk, but it can still fail.
I know you always dive with the same Op as you have for years, and I know them to be a fine Op to my limited experiences - but last I heard they were filling their own tanks. Do you know if they run inline CO monitors?
In Cozumel? Who cares where they died? CO can show up anywhere. Cozumel isn't exempt.
In fact, given the way dead tourists are handled in Cozumel, it's unlikely you could find proof that anybody was killed by anything in particular. It's bad for business and tends to "go away" quickly.
And yes, you can bet that when I dive in a place with where the tanks magically show up at the boat, with no VIP sticker, no recent hydro stamp and no indication who owns them or who filled them, I'm going to check the gas.
Saying there have been no proven deaths from CO in Cozumel is like Galileo saying he hasn't detected neutron stars. It's correct, but doesn't mean they don't exist. CO poisoning in tourist locations is often written off as a heart attack or drowning, which Coz seems to see quite frequently.
DMs are typically in better shape than tourists, use less air, breathe less, are younger, are more likely to go home and complain about a headache than make a stink about air quality.
flots.
I'd say that's a realistic appraisal. I don't know if the local hospital has the ability to test for carboxyhemoglobin (HbCO) in blood yet, but patient privacy rules would prevent us of knowing results anyway. Tank CO analyzers were non-existent on Coz is past years, but while that is changing - I don't think they have scuba police who show up immediately with ambulances to test tanks before they can get lost. It's just not going to happen. The DMs seem to have fared better than the tourists on the group hit at the Occidental Grand a few years ago. See
http://www.scubaboard.com/forums/ne...ned/324039-carbon-monoxide-tanks-cozumel.html Whether tanks or blood was tested was never made public. A surprising statement excerpted from that report:
"We learn that on the 10:30 am dive there were 2 incidents similar to our 2:00 pm dive, however, there was no mention of the problem or mention of stopping the dive or any concern. The only thing that they may have done to minimize the problem was there were two dive masters with us on the dive. But that may have exasperated the problem because instead of stopping the dive after the first diver went up – they continued the dive with the one dive master until the 2 other divers went unconscious." The hotel changed house Ops within a week tho.
Is Coz more dangerous than the rest of the Caribbean for CO risks? No, I don't think so at all. It's a risk anywhere. Some of us are keeping the testing & reporting pressure on at Coz more so maybe it's safer. I still don't agree with DAN's approach of gifting a few inline monitors to selected compressors in the area, but maybe they are being used right.
The bottom line is the only way to
know about any tank, anywhere, is test it yourself. Past performances really are no guarantee, but your call...