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Personal breathalyzers: Worth the blow?

Personal breathalyzers: Worth the blow?

(CNN) -- Affordable, compact and widely marketed: Consumer-based breathalyzers are becoming more widely used by individuals and the bars they frequent. But how accurate are these devices? Should we trust them? To answer these questions, our brave Bruce Burkhardt gets tipsy on the job and tests the consumer breathalyzers for accuracy. Lieutenant Cliff Miller, a DUI training officer, offers his advice.

BRUCE BURKHARDT: You've stopped how many drunk drivers?

LIEUTENANT CLIFF MILLER: I've been on the state patrol for almost 24 years and spent a lot of time on DUI task force, and probably between 3,000-5,000 DUI drivers I've arrested in my career.

BURKHARDT: What do you look for?

MILLER: Well the first thing you look for is the driving cues. Could be speeding, but sober people speed too. Driving at night with your headlights off, weaving over the center line or over the fog line, and running red lights. There's just a lot of cues that may be indicators that they're drinking.

BURKHARDT: When you stop them and you look at them for the first time, what are you looking for?

MILLER: Well really, you smell first -- you use all your senses. What you see, what you hear, what you smell. First thing you'll do is probably smell an odor when you talk to them, whether it be vodka, beer or whatever. Then you'll listen to their speech, see if it's somewhat distorted, maybe a little slow. You'll look at their eyes, they may be red and glassy. You'll watch their mannerisms, when they hand you their license. I've had them give me their Sam's club card, their Visa card, or whatever, thinking it's a driver's license.

BURKHARDT: What is it that makes you decide "I'm going to give this person a breathalyzer test"?

MILLER: How they perform on the field evaluations and my observations. What I've seen and what I've heard and what I've smelled.

BURKHARDT: The police breathalyzer, what's the basic principle, how does it work?

MILLER: The one that we use here in Georgia has infrared screens to read out the different levels of alcohol. It also filters out stuff that may interfere. The machine will void the test so it won't give an inaccurate reading.

BURKHARDT: How does your breath have alcohol content?

MILLER: You're getting air from the bottom part of your lungs, which is made up of blood and the alcohol gets in there. So you get a reading based on the amount of alcohol in your blood.

BURKHARDT: Do consumer versions of the breathalyzer work on the same principles as the police versions?

MILLER: Yes, they do. Some of them may not have an infrared screening device or a fuel cell, but they do work on the same principle and that's where you get into the accuracy question. Don't take a drink, then two seconds later blow into it because you're going to have mouth alcohol and that's abusing the breathalyzer. A good rule of thumb is to wait about 20 minutes from your last drink.

BURKHARDT: Don't most people have a pretty good sense of when they've had enough to drink? Do you need a breathalyzer?

MILLER: Unfortunately you do, because the alcohol affects the brain. Alcohol is water soluble. It goes to all the organs and all parts of the body that have water. And the brain is the one that has the most water so it affects the brain the most. You're not going to think you're impaired. You're going to think you're fine. And that's the problem, when you get close to the legal limit or even above the legal limit, you'll still think that you're fine.

BURKHARDT: How much alcohol does it take to be impaired, where you could be dangerous?

MILLER: Well, that's based on the individual. A new drinker, they're going to feel the effects after one or two drinks. Now someone who drinks on a daily basis may take them long to feel the effects. The alcohol is still affecting them, but it may take longer for them to feel the effects. But alcohol really starts to affect your judgment at 0.04.

I'll tell you a rule of thumb I give people: If you can average one drink an hour, you won't be above the legal limit. Now a lot of people can't do that, and people think that if I drink a lot of coffee or if I go to the bathroom a lot, then the alcohol's gone. And that's not true. The only thing that dissipates alcohol is time. And the other thing that the public needs to know is that one drink isn't a Long Island ice tea. A Long Island ice tea has five to seven ounces of alcohol in it. That's equivalent to five to seven drinks.

BURKHARDT: Should someone make a decision to drive or not, based on these other types of breathalyzers out there?

MILLER: That decision you should make even before you start drinking. If you know you're going to consume an abundance of alcohol, you need to make plans ahead of time to either have a cab or a friend come pick you up or carry a designated driver.


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