How do Breathalyzers Work?
We hear and read about drivers who are charged with DUI after an accident, and usually a news report on the accident will say what the driver’s blood alcohol level was and what the legal limit for blood alcohol is. A driver might be found to have a level of 0.15%, for example, and the legal limit is 0.08%. But what do those figures mean and how do police officers find out if a driver they suspect has been drinking is legally drunk? You have probably heard about the Breathalyzer, but may wonder exactly how a person’s breath can show how much that person has had to drink. It is important for public safety that drunken drivers are taken off the roads. Of the 42,000 traffic deaths in the United States in 1999, about 38 percent were related to alcohol. Drivers who can pass roadside sobriety tests — they can touch their noses or walk a straight line — still might be breaking the legal limit for blood alcohol and therefore are a hazard on the road. Police officers use some of the latest tec
