Picture this. You are driving your usual route to work one morning. Everything is going just fine when, for no reason, the car in front of you brakes suddenly and you hit their rear bumper. You know it's your fault - you should have kept a safe braking distance - so you are relieved that the other driver is polite and understanding about it. After all, it can happen to anyone, can't it?
As you exchange your insurance details and work out how to clear the road to let traffic pass, a police car pulls up. The officer requests a routine breath test and you are both happy to oblige. You would never drink and drive and, in any case, it's not even 9am.
The other driver's test blows clear, of course. Then it's your turn. You blow. The intoximeter makes a beeping sound and the police officer's expression changes as he informs you that your test indicates that you are over the drink-drive limit. You are arrested on suspicion of driving or attempting to drive while above the legal limit or unfit through drink.
Less than an hour later, you're at the police station being charged with the offence.
How could this happen? After all, you are not a closet alcoholic who downs a pint of vodka for breakfast. And you would never drink and drive. Your licence and your reputation are far too precious, plus you know the risks.
But you did have a few drinks late last night. And you simply didn't realise that it was enough to leave you over the limit the next morning. Which is probably why you misjudged your braking distance. And why you now face a drink-drive conviction with all the associated stigma, shame and inconvenience, not to mention losing your licence.
Nearly one in five drink-drive incidents happen the morning after a drink.
In Swanswell's experience, these are often not people who have willfully decided to get behind the wheel with alcohol in their system. They are people who just didn't know that they could still be unfit to drive several hours, and a decent sleep, after their last drink.
Whether they are a professional driver, a business person, a parent on the school run, or a sales rep dashing to the first appointment of the morning, they are often shocked and confused by the result of their breath test, and totally unprepared for the charges and criminal record that follows.
If you drink alcohol, and sometimes have several drinks late into the evening, then drive your car in the morning, you are risking a drink-drive limit shock.
Alcohol impairs driving, so the consequences for you, your loved ones, or complete strangers could be serious, or even fatal. It may not be just your licence that you lose.
A total of 290 people were killed in drink-drive accidents in 2012 - a quarter up on the previous 12 months.
Not drinking any alcohol at all would provide certainty, but I accept that people want to take a drink from time to time.
Here's the moment for me to be clear that drinking and driving don't mix. From our experience, the only safe amount of alcohol when you are getting behind the wheel is none. You may disagree with this - if so, drop a comment in the box below this blog, I'm interested to hear from you. But if you want my advice - professional and personal - don't drink and drive. Ever.
What about the people who would never knowingly drink and drive, but who may be risking being over the limit the morning after? If you enjoy a drink but want to be safe to drive next day, here are the three options available to you:
You can learn all about how your body processes alcohol and the rate at which it is eliminated from your system. This is a complex and not terribly precise science, and you can find out all about it here. Let me know how you get on with this by dropping a comment below this blog. I'd love to know what you make of it and whether it's helpful to you.
As a rule of thumb, allow one hour to pass for every unit of alcohol you have consumed. So a two-unit glass of wine before 10pm will be clear of your system by midnight.
However, this is not precise, it requires some maths (and the bit of your brain that does maths tends to check out first when you drink alcohol). Plus you have to understand those pesky units which, as far as I can tell, very few people do. You can find a simple calculator on our website.
However, please be careful. If you've read the science in option 1, you'll know that different people process alcohol at different rates for all sorts of reasons. So allow yourself a good margin for error before deciding to get behind the wheel.
We recommend adding another two hours for safety. Let me know whether you think the simple calculator will work for you by posting a comment below this box, it's always interesting to know what works and what doesn't work so well.
Simple home-use breathalysers are readily available. As one of my team members (who delivers courses to people convicted of drink driving, so she knows what she is talking about) pointed out to me, these are not as reliable as the intoximeters used by the police. She would much rather you take option 1 above to learn and apply the science of alcohol elimination rates. While I don't disagree with her, I also realise that understanding and applying the science isn't for everyone.
So, if you want a quick way of checking whether you are likely to be affected by last night's alcohol, keep a home breathalyser handy. But please bear in mind the sound advice we give on our courses:
The only safe amount of alcohol in your system is none. And, as home breathalysers are a guide only, don't choose to drive if you think you're still affected by last night's alcohol, even if the breath test is clear.
Would a home breathalyser be a good choice for you? Post below to let me know what you think.
You can find information about easily available home breathalysers, and even enter Swanswell's competition to win one free on our shop. You might be shocked by your results, but it's better to be shocked in the comfort of your own living room, than by the side of a road with a police officer.
The bottom line is that alcohol and motoring don't mix.
Don't drink and drive. Ever.
And whichever option you take, please avoid the drink-drive limit shock.
Have you got a friend who enjoys an evening drink and drives the next day? Share this page so they know how to avoid the drink-drive limit shock too.
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This blog was originally featured on the Swanswell website.