Over 1,000 people die in boating accidents every year. Nine out of ten of them drown. About half of those deaths involve alcohol. Four hours of exposure to powerboat noise, vibration, sun, glare, wind and more produces a kind of boater's hypnosis. This slows reactions almost as much as being legally drunk. Adding alcohol to this sun exposure intensifies the effects. As the chart shows, sometimes just a couple of beers is too many. When you're "tipsy," you're much more likely to fall overboard. Alcohol also reduces your body's ability to protect against cold water. Within minutes you may not be able to call for help or swim to safety. A drunk person whose head is immersed can be confused and swim down to death instead of up to safety.