For years, the suggestion for people who are planning on going out and having a few drinks at a restaurant, bar or friend’s house has been to assign a person to be the “designated driver.” It seems like such a sensible idea, to have one person along who does not drink any alcohol, remains stone cold sober and can drive the rest of the revelers home. Perhaps it is a little too sensible for the average group planning a night out in Honolulu or anywhere.
At least it was for individuals interviewed by a study published in the Journal of Studies on Alcohol and Drugs. They were patrons of bars in Florida, consisting mostly of white male college students. The study found that of the 165 persons identified as designated drivers, nearly 40 percent had been drinking and had measurable blood alcohol content (BAC) readings up to 0.05 percent. Worse, 18 percent had a BAC greater than 0.05, and some of that 18 percent could have been arrested for drunk driving, possessing BACs greater than 0.08.
The flaw in the plan many used was the designated driver was often the person who was least drunk. This is probably not how designated drivers should be ideally chosen. The study also employed additional test to determine how behavior changed among those who were drinking.
Those with 0.05 or higher exhibited more changes in their psychomotor function and their ability to drive. The National Transportation Safety Board (NTSB) has recommended that the national standard for drunk driving be lowered from 0.08 to 0.05, a limit the average male reaches after two drinks.
After someone has begun drinking, the alcohol impairs their faculty for judgment, meaning they can no longer determine how much is too much. The designated driver must be chosen before anyone has had a drink and they must refrain from drinking any alcohol.
Source: CBSNews.com, “Study: One-fifth of designated drivers impaired behind wheel,” Michelle Castillo, June 10, 2013