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July 2012    Download the Entire Issue (PDF) Available to the Public Vol. 38, No. 7   RSS Feed for Undercurrent Issues
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CO Poisoning Risk Higher Than You Think

why and how divers need to protect themselves

from the July, 2012 issue of Undercurrent   Subscribe Now

On March 4, Ronda Cross, on vacation in Baja California from Calgary, Alberta, went diving off Cabo San Lucas  with her cousin, Roxanne Amundson and divemaster Jorge Duchateau. When Amundson and Duchateau surfaced from their dive to 75 feet, Cross, 41, was not with them. Her body was found floating in the water nearby and pulled out by the crew of another boat. Her husband, Colin, believes she was overcome by carbon monoxide in her tank, fell asleep and drowned. A report in the Mexican online publication Sudcaliforniano stated Cross's cause of death was asphyxiation by drowning, as did a woman employed by the funeral home that received Cross's body.

Amundson and Duchateau both said they felt sick on their dive, and had little strength and trouble breathing when they surfaced. "I was dizzy in the last three or four minutes of the dive, Duchateau told the Calgary Herald. "I was having a super strong pain in the chest. I wasn't really aware of anything." But he declined to divulge where he got his tanks filled.

Colin Cross told the Calgary Sun he was taking legal action, hiring a lawyer in San Diego, and he warns everyone considering a dive trip in a developing country to ensure the rental tanks have been properly filled and inspected before using them. "The blame has got to be put squarely on who filled up those tanks."

The author of the article published below, a diving physician and a fill station consultant for government and businesses wishes to remain anonymous, due to the multiple hats he wears professionally. He believes the blame for foul air should not rest entirely with the dive shops. Responsibility should also be taken by the dive agencies -- and divers themselves -- to reduce the risk of carbon monoxide poisoning. He wrote an essay on the topic for Undercurrent to explain his reasoning for why the risk of CO poisoning is higher than we all think.

* * * * *

Let's start with some history on compressed air testing in the sport diving industry. In the past, PADI required all its five-star resorts and dive shops to test their compressor air quality quarterly. For the first year of a facility's operation, it was also required to send these results to PADI headquarters. After that, the fill station would have only to keep the results "on file," so there was little enforcement after the first year, unless a compressed air quality problem was brought to PADI's attention. However, this requirement did serve to create industry awareness that compressed air quality should be monitored regularly.

NAUI has a code of ethics that cites a quarterly testing frequency; however, there is no enforcement, and many NAUI shops I have visited have no current testing certificate available. In fact, many of these shops were unaware of this code. I wrote NAUI several times about its high rate of non-testing at their facilities, despite its guidelines specifying quarterly testing, but never heard back from them.

(Note: Undercurrent contacted NAUI about its policy on preventing CO poisoning, and what its dive shops are required to do regarding air fills for divers. Randy Shaw e-mailed us three articles from NAUI's former medical adviser Kelly Hill, and told us NAUI's answer is contained in those stories. The articles, published in 2002, 2004 and 2005, are primarily Hill's commentaries about the Centers for Disease Control and Prevention (CDC) investigations of CO poisoning in swimmers at Lake Havasu, AZ, and Lake Powell, UT, and a CDC stat that 15,000 ER visits annually are due to non-fire CO poisoning. None of the articles mentioned anything about CO poisoning in divers, nor did they mention anything about NAUI's guidelines for testing for it.)

The Lawsuit That May Have Changed Everything

The quarterly air-testing requirement changed substantially in 2009 or thereabouts, when PADI settled a lawsuit brought against CoCoView Resort in Roatan and PADI headquarters by the estate of the late R. Gibbs. Gibbs, a Texas native, and a CoCoView divemaster both died in 2005 after breathing from a tank that contained excessive amounts of CO, as indicated in the plaintiff's statement of facts. There were once long threads about this incident on both ScubaBoard and CoCoview forums, in which several divers at the resort that week indicated that the contaminant was CO, but the owners of Scubaboard and CoCoView Resort subsequently removed both threads.

The deceased's attorney argued that the fill station was in fact manufacturing a product -- compressed air -- and this product was defective, which resulted in the two divers' deaths. I am not an attorney, but I have been told that the burden of proof for product-liability law is much lower than if one was to try to show that the fill station owner/operator was negligent. The manufacturer of compressed air had a duty to produce a product that would not harm the consumer. All that was needed was for the plaintiff to show that the manufactured product, compressed air, contained a contaminant that killed the diver, akin to showing that an undercooked hamburger that contained E. Coli 0157 resulted in a person's injury or death.

The details of the settlement were never made public; however, shortly after the settlement PADI decided to remove its compressed breathing air quality assurance requirements (quarterly testing to the Compressed Gas Association's Grade E specification) for its affiliate shops and resorts. This is presumably because the outcome in this case using product liability law would leave PADI very exposed to future liability, given that so many of its shops and resorts were not testing as required and enforcement was difficult. Instead, PADI would now defer to the local authority having jurisdiction over compressed breathing air quality, which, unfortunately in almost all sport diving locations, has translated today into little to no testing of sport diving air. In many jurisdictions, there are requirements for commercial divers under the local labor code, but most of these standards specifically say they don't apply to the sport diving industry.

(Note: Undercurrent called and e-mailed PADI about its policy and guidelines on air fills, testing them, and prevention of CO poisoning, but PADI failed to respond.)

Where Can You Get a Good Air Test Around Here?

Therefore, the sport diving industry went from having some semblance of a quality assurance program for compressed breathing air in 2009 to one today where its largest training agency has ended its quality assurance program, arguably the most important safety concern for divers -- a fact that very few sport divers are aware of. The situation today is that there is no (major) training agency "enforcing" any sort of quality assurance for compressed breathing air, except for American Nitrox Divers International (ANDI), which, according to its website, requires all its affiliates to send in their "quarterly" air tests to headquarters, but whether this actually happens on the ground today is not known.

In terms of government enforcement, Florida is the only state I am aware of that requires its dive shops to routinely test their compressed dive air. While the program might sound like a step in the right direction, it has its drawbacks. Should the dive shop fail a test, it is not required to report the test failure to the Department of Health, rather only to rectify the situation and send in the re-test pass. Florida requires that a quarterly test be taken, which must meet the Compressed Gas Association's Grade E specification, and goes one step further by requiring that an "accredited laboratory" be used to test the air.

The sport diving industry went from having
some semblance of a quality assurance program
for air to one where its largest training
agency, PADI, has ended that program."

It has become the Wild West out there for sport divers with regard to any sort of air testing, and it is becoming more difficult to find dive facilities where one can locate quarterly tests being done, despite all U.S. and Canadian fire services requiring their compressor stations to test regularly (quarterly in the U.S. and biannually in Canada). Sean Sheldrake, a unit diving officer for the U.S. Environmental Protection Agency, wrote a 2009 article expressing his concern that many shops in his Pacific Northwest region stopped testing once they realized PADI was no longer going to enforce the quarterly Grade E testing requirement. "You can't count on an unfamiliar shop testing their air in all instances," he writes. "This also goes to show that a shop you've used for years might stop air purity testing without informing customers."

Regarding the role of Diver Alert Network (DAN) in this safety issue, it has been silent until recently, when it donated 10 Analox fixed compressor CO monitors to shops in Cozumel and Playa Del Carmen, after the number of CO incidents in the region continued to mount. It was odd, as there was no explanation why only this area received the monitors, and what the rationale was behind the donations. One suspects it was due to recurrent ScubaBoard reports of divers finding CO in their breathing air, plus several injuries and a CO-related fatality over the last 24 months. That fatality, occurring in October 2011, apparently happened even with CO monitors at the compressor station in Cozumel, but based on my personal observation, these monitors were originally located in a walled-off compressor room where the operators wouldn't have been able to hear the alarms while filling tanks on the plant floor away from the noisy compressors.

(Note: We contacted DAN about whether it tracks dive deaths connected to CO poisoning. Its reply: "No, we do not have specific statistics on the percentage of dive deaths caused by CO poisoning." When we asked DAN the reason for donating the CO monitors, it replied, "Cozumel is a destination visited by many DAN members. In recent years, there has been more than one instance reported where contaminated air was suspected as the cause of a diving accident. In order to minimize the likelihood of this happening again, DAN and Analox Technologies teamed up to donate CO monitors to the facilities in Cozumel who fill tanks for recreational divers.")

One must wonder why DAN has not aggressively pursued this important safety issue, but any talk of contaminated air in the sport diving industry is simply bad for business. DAN's financial well-being relies on good relations with the dive industry. PADI and NAUI are both listed as Corporate Guardians, and Undercurrent has written in the past of PADI's influence with DAN. Regardless, it would be important for DAN to step up.

The accredited U.S. compressed breathing air laboratories still report a CO failure rate of 3 to 5 percent for "dive" compressed air samples received from around the globe. Air samples for the U.S. fire service air samples have a CO failure rate about one-tenth that of the global dive centers. It should be remembered that unlike fire fighters who breathe any CO contamination at only 1 atmosphere absolute (ATA), recreational divers may travel down to 5 ATA, where the CO partial pressure and resulting toxicity will be five times that found on the surface.

How Divers Can Protect Themselves

In light of the insufficient frequency of air quality testing for sport divers, plus the continued global sporadic identification of CO contamination in dive air, the only acceptable solution to this problem is for each diver, or group of divers, to carry a portable CO analyzer to test each and every tank prior to use, much like the Red Cross tests every unit of blood for HIV and hepatitis B and C prior to transfusion. In the long term, one would hope that the dive industry will encourage all fill stations to have a quality assurance program that includes, at a minimum, quarterly air testing, but with the recent availability of affordable in-line CO monitoring (less than $1,200 for the Analox CO Clear with all the regulators), this should become a routine compressor requirement as well. However, I don't see a day anytime soon when all fill stations will have in-line CO monitors, because compressed air quality is not seen as a priority issue by the dive industry, and discussion of the contamination issue is bad for business.

Individual countries should also develop a compressed breathing air standard and the means to enforce it, but I don't see this happening in the popular dive destinations, given our current economic climate and reluctance to introduce additional government regulations. Thus, every diver must become responsible for ensuring his breathing air is CO-free. Just as every diver double-checks his oxygen content in a nitrox tank prior to a dive, the training agencies need to begin to train divers to check every tank for CO contamination prior to a dive. While the frequency of CO contamination in dive air may be low and sporadic, the health consequences of breathing CO-contaminated air gas underwater are high, even more so because CO is tasteless and odorless. The only way to detect its presence is by using a portable analyzer before the dive.

There are really only two portable diver-dedicated CO analyzers I would recommend right now -- the Analox CO EII ( ) and the Oxycheq CO Expedition analyzer ( ). Both cost about $340 from resellers if one shops around. These units will take a reading in under 30 seconds. I prefer the Analox unit, as it has the backing of a company involved with contaminant detection not only in the sport diving industry but also in the military and commercial diving industries.

If you don't want to spend the money for a portable CO testing device, a company called Outdoor Equipment Rentals rents the Analox CO EII for $35 a week ( ), although let's hope the outfit keeps these units in calibration, as per the Analox manual, which requires them to be sent back to Analox at least annually for a formal calibration.

I used to think sport divers should routinely ask if a dive shop or resort regularly tests its air quality, but in my recent experience, only about 25 percent of shops in the tropical tourist areas are testing at all. In many jurisdictions, there is no testing whatsoever. I now believe it is much safer for the diver to carry a portable CO analyzer and to smell the breathing air for the presence of odorous hydrocarbon volatiles rather than to worry about whether a shop has tested its air or not. Plus, the reality of periodic testing is that the air was only clean at the time of the test, and much can happen in the intervening three to six months to allow the production of contaminated air.

The one thing a sport diver can also do at the fill station is ask to see the compressor. If it's buried in the back of the shop under a film of oil, or if the owner won't show it to you, then look for another dive operator. Also, you can look at the location of the compressor's intake relative to any potential point source risks for contaminants such as vehicular or boat exhaust, BBQs, generators, petrol pumps, stored chemicals, etc.

What hopefully will happen over time is that there will be a CO analyzer on every dive boat, much as we now have for nitrox analyzers. As more divers show up with their own CO analyzers, signaling the importance of this issue for them, the greater the likelihood that the dive compressor operators will install inline CO monitors on their compressors.

It would be great if the US-based dive training agencies would specify what minimum breathing air standard their affiliates are expected to follow to ensure the quality of compressed breathing air. Unfortunately, now that PADI has settled a product-liability lawsuit for a CO-related fatality, I suspect, that none of the other agencies will want to develop compressed air quality recommendations or enforce the policy in an effective way. Instead, as PADI has done to reduce liability risk, the training agencies will defer to the local authority having jurisdiction that, in most locales, except for Florida, will translate into no compressed air testing whatsoever.

I suspect that if a city told its residents it was no longer testing for E. coli in the drinking water, most people would stop drinking that water or want a testing device for E. coli to use at home. With the largest dive training agency on the planet no longer requiring its affiliates to test their breathing air quality on a quarterly basis, the time has come for individual divers to routinely carry a CO analyzer so that they can test for this odorless, tasteless and toxic contaminant in their tanks and prevent themselves from becoming a possible fatality.

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