Designated Drivers Don’t Always Abstain

You’re going out on the town for the night. Everyone wants to have a good time, likely drink, and doesn’t want have to worry about getting home, thus a designated driver is elected – the person who is supposed to remain sober for the night and be responsible for getting everyone home safe and sound.

But according to new research from the University of Florida, you should take cab fare or have a backup plan just in case, as they found many would-be designated drivers imbibed enough libations – saturating blood-alcohol levels – to the point of legally defined impairment under the newly proposed National Transportation Safety Board standards.

Adam Barry – an assistant professor of health education and behavior at UF – alongside co-researchers Beth H. Chaney and Michael L. Stellefson, both assistant professors in health education and behavior – performed the study.

The team interviewed and breath-tested 1,071 bar patrons – mean age 28 – as they left downtown restaurants and bars within a major university town in the Southeast.

Participants were screened between 10 pm and 2:30 am over the course of six Fridays during the fall 2011. The majority of those who volunteered to be tested were white male college students.

After completing a five minute interview about demographic data and alcohol-related behaviors, participants then had their blood-alcohol content tested with a hand-held breathalyzer.

Non-driving participants had significantly higher levels of blood-alcohol concentrations than the designated drivers, but 35 percent of the 165 self-identified designated drivers had been drinking.

Seventeen percent of all those drivers tested had blood-alcohol levels between.02 and.049 percent, while 18 percent were at.05 percent or higher. Of the designated drivers who had consumed alcohol, half recorded a blood-alcohol level higher than.05 percent.

The National Transportation Safety Board has recently recommended that all states cut their legal drinking limit from.08 percent blood alcohol content to.05 percent, which means by these terms the DDs would be illegally intoxicated.

It would take a 170-pound man consuming three beers in an hour or a 100-pound woman sipping down two beers to hit.05. Which means if passed the NTSB measure would criminalize many social drinkers who feel they are perfectly sober enough to drive.

Currently, at.08 percent, the US has one of the highest allowable legal limits of any developed country. Countries such as Denmark, Finland and Greece use the.05 level; Russia and Sweden are at.02; and Japan has a zero percent tolerance.

There is no universally accepted definition of a designated driver, but most say drivers should completely abstain from alcohol given that it’s tricky for anyone to accurately evaluate their own sobriety otherwise.

Many drive on a light buzz, failing to realize that any type of physical effects felt from drinking, even slight, means you are impaired and should not get behind the wheel.

The results will be published in the July issue of the Journal of Studies on Alcohol and Drugs.

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