How to Blow a .08

The National Traffic Safety Board announced last week that it is recommending lower standards for drunk driving in all 50 states and requesting to move the threshold from .08% to .05%.

We've all seen the commercials and the billboards - .08 Don't Blow It. What does that mean though?

BAC is the Blood alcohol content of a person's blood, expressed in a percentage. If a person has a BAC of .10, then one-tenth of one percent of a person's blood, by volume, is alcohol. Obviously, the higher the number the higher the percentage of alcohol volume in a person's blood.

I'll post on the reasons behind the current law and the motives to change it later this week, but today I wanted to give you a glimpse into how BAC is calculated based on forensic toxicology.

Every alcoholic drink increases a person's blood alcohol. A drink is a regular size beer, shot, or glass of wine. The amount it increases blood alcohol depends on a number of factors like gender, body weight, food consumed, metabolic rate, and frequency of drinking. We'll look at a 180 pound man who is drinking normally and has not eaten.

I'm certain that I'll get some messages from people explaining how wrong the science behind all this, but so be it. Generally, one drink will increase a person's BAC .02. Click here to see a chart.

How many drinks to get to a .08?

1 Hour:

.065

Four drinks in an hour will get a person to .08. But the moment you start hitting the bottle, your body begins processing and eliminating the alcohol from the blood. After this point, we have to start factoring in how much alcohol is eliminated in an hour. Generally, around .015, or .015% is eliminated an hour. Basically, one drink an hour is eliminated from your body.

A person is under the current legal limit.

2 Hours:

.07

You were at the .08 from the four drinks the first hour. But the body is still getting rid of the booze. Add in another .02 for the extra drink, but your body has gotten rid of a drink and a half at this point (.015 per hour or .3 for two hours).

At 5 drinks, a person is under the legal limit, but toeing the line.

.09

6 drinks takes the total to .09, above the legal limit.

3 Hours:

.095

Another beer for 7 total (.02) and another elimination (.015).

6 beers in 3 hours? .075

4 Hours:

.10

Another .02 added and another .015 subtracted.

7 Beers in four hours? .08

These are just rough calculations to show you how much a person needs to drink to get to the current legal limit. Remember a person can still be intoxicated at any number if the alcohol has impaired them enough that they shouldn't be driving a car.

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