Doing the maths on alcohol blood levels

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How many standard drinks is in that cocktail? It might not be a question you would normally ask, but you perhaps should, if you’re going to be driving and want to be safe and avoid failing alcohol testing.

Will alcohol testing catch you out?

You’re a responsible person. So, when it comes time to go out with friends or family and it’s your turn to drive, you want to do the right thing and make sure you won’t be caught out by alcohol testing at the end of the night. More to the point, you want to make sure you’re safe to get everyone home.

So, the question is, how much alcohol can you drink before you will be unsafe to drive? And, how much can you drink to make sure you’ll be safe if asked to undergo random alcohol testing on the way home?

Firstly, let’s look at the basic science. It takes around one hour for the body to break down one standard drink. That’s one standard drink, not one can of beer, not one glass of wine and not one bottle of pre-mixed alcohol. All these can often be more than one standard drink, so you need to take this into account.

We also know that that men can generally consume two standard drinks in the first hour and one standard drink each hour following to stay under the 0.05 blood alcohol limit. For women, the equation is generally one standard drink in the first hour and one standard drink each hour following.

You might notice in the above sentences, however, the word generally. That’s because when working out what you might blow during alcohol testing or whether you are safe to drive, there are factors involved that might mean you’re blood alcohol is higher or lower than expected. For example, your sex, body size, body fat and other individual factors can affect your alcohol processing time. Whether you eat before and while drinking, your health and other factors, some of them intangible, can also impact on the time it takes for you to process alcohol.

So, if you are responsible person, you don’t want to fail alcohol testing and you don’t want to put your safety and the safety of others at risk, you’ll want to be more sure, and lower the number of standard drinks you consume or wait longer before getting behind the wheel.

How can I make sure I’m safe and I won’t fail alcohol testing the next day?

Working out if you are safe to drive and won’t fail alcohol testing the day after a big session on the alcohol is even trickier. While science and maths can help, when most of us drink we’re not really good at counting how many standard drinks we’re consuming, or what time we started drinking and what time we finished.

So, again, play it safe and make sure you allow for a good margin of error.

What about things to help speed up the process of eliminating alcohol from your system? Things like having a cold shower, drinking lots of coffee, getting fresh air and getting a good night’s sleep? All these things may help you feel a little better but they do nothing to lower blood alcohol levels.

The only thing that can do that is time!

NOTE: See https://www.myvmc.com/tools/blood-alcohol-concentration-calculator/ for an online blood alcohol level calculator. But, remember, this tool is a guide only.

IMAGE CAPTION:

How many standard drinks is in that cocktail? It might not be a question you would normally ask, but you perhaps should, if you’re going to be driving and want to be safe and avoid failing alcohol testing. Credit Dani Figueiredo (https://www.flickr.com/photos/danifigueiredo/45812187992/).

By Michael

Michael is the founder of Integrity Sampling and is responsible for overseeing all national operations. He is based at Integrity Sampling's head office in Melbourne and is also responsible for the co-ordination of drug and alcohol testing within Victoria, assisting in the implementation of drug and alcohol (fit for work) policies and the presentation of drug and alcohol education and awareness programs. You can connect with Michael Wheeldon on LinkedIn

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