In many quarters, alcohol has been woven into the social fabric of sport diving. You probably know some divers
who spend much of the evening at the bar between dive days. Such behavior is still prevalent, as described in a
recent issue of Diving and Hyperbaric Medicine. A research team at the Diving Diseases Research Centre in Plymouth,
England, sent an anonymous questionnaire to divers in the fall of 2010 to collect information on their health, diving
and alcohol consumption, especially around diving.
One question focused on the diver's understanding of the U.K. government recommendations for alcohol intake.
An alcohol "unit" was defined as equal to 8.5 ounces of standard beer, 0.8 ounces of spirits or 5.9 ounces of red
wine. The daily recommended limit on units is two to three for men (11-21 per week) and one to two for women (8
-14 per week). Binge drinking is defined as drinking more than double the daily limit.
They got 818 anonymous responses; 80 percent were male. Older divers were more likely to exceed the recommended
weekly alcohol units compared to younger divers, but binge drinking was associated with younger divers.
Nineteen percent of respondents went diving even when considering themselves unfit to drive a car; 23 percent
had witnessed a diving incident that they felt was attributable to alcohol. Only 38 percent of respondents reported a
responsible attitude to alcohol by their dive clubs, both under normal circumstances and while on a dive trip.
Some respondents wrote comments on their questionnaires, like this diver who wrote, "Many people in our
diving club still drink heavily during a diving weekend. One experienced diver is well-known for sinking a couple
of pints at lunchtime in between dives. There can be a lot of pressure on people in a club/group situation to drink
whilst away on a diving trip, whether [in the] U.K. or abroad."
Another wrote that during his 20-plus years of diving, he had witnessed and dealt with several DCS incidents
that were undoubtedly tied to alcohol consumption that led to dehydration. "Some of these DCS events were quite
serious. Despite warnings, some divers were determined to drink multiple units of alcohol on Friday night and dive
on Saturday morning. Ignorance of the consequences of alcohol consumption with diving is common, but some divers
are willfully in denial."
In his regular "Letter from the Editor" page, Diving and Hyperbaric Medicine editor Michael Lewis stated that
over his half-century of diving, he has regularly witnessed divers (and, when younger, participated himself) drinking
to excess for an evening, then diving the following morning. "Such behavior seems relatively common, even
among diving medical practitioners, who should perhaps know better. Almost certainly excessive alcohol intake
contributed to one case of neurological decompression sickness at a scientific meeting some years ago. Thus, both
the evidence from the U.K. survey and anecdote show that drinking alcohol whilst diving is commonplace amongst
recreational divers."
But dive experts know little about the relationship between alcohol and diving mortality. In an analysis of
100 consecutive scuba deaths in the 1980s reported in Project Stickybeak, an investigation by the South Pacific
Underwater Medicine Society, "excess alcohol" was recorded in the blood of only four divers, though not all divers
were tested. In a review of snorkeling- and scuba-related deaths in New Zealand between 1980 and 2000, a
blood alcohol level was measured in only 43 percent of the 169 bodies undergoing autopsy. Five of 24 snorkelers
and four of 48 divers had a positive blood alcohol, but in only three drownings was this considered a possible
contributing factor.
So, while for decades most dive operators have said one drink and you're done diving for the day, it looks like
the Brits, at least, are not paying much attention when they're out on dives.
"Alcohol and UK recreational divers: Consumption and attitudes," by Marguerite St Leger Dowse, Christine Cridge, Steve Shaw and Gary Smerdon; Diving and Hyperbaric Medicine, vol. 42, no. 4, pgs 201-207.