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How drinking and driving contributes to road accidents

[fa icon="calendar"] 10/25/17 6:01 PM / by SAMTRAC


Cover image 25 October 2017.jpg

Like driving and using your mobile phone, driving after you’ve been drinking is not just stupid, it’s dangerous. That may be strong language, but time and again research has shown the negative consequences, both on you and other road users, when you get the behind the wheel after a few.


Why are people so blasé about driving after drinking?

Many people – and more than you’d realise – still believe it’s okay to drive after consuming alcohol. And we don’t just mean those who are clearly wasted – we’re talking about those with just a drink or two under their belt when they decide to drive home. How often have you heard, ‘I’ve only had three beers, and it was over the course of a whole night. I can drive’? It sounds perfectly reasonable – surely if you know your own body, what the legislation says is really more a guide, right? WRONG.  


The laws around driving while under the influence are there for a reason. So let’s break it down.


Why does alcohol have the effect it does on us?

Because it’s a depressant, alcohol slows down the brain and affects the body’s responses. At the same time, if you’ve been drinking, you’re more likely to take risks. Combined, these reactions increase the chance of accidents happening. Drinking impairs your senses (vision and hearing) and results in decreased muscle coordination and slower reaction times – not a good combination for driving a car. 


5 physical consequences of drinking

Drinking alcohol can:

  1. Affect our judgement and reasoning

Your brain controls how you judge certain circumstances. When operating a motorised vehicle, your judgement skills play an important role in how you make decisions. For instance, you need to be able to foresee potential problems and make clear decisions if another vehicle cuts you off. Your judgement helps you stay alert and aware of surrounding conditions while driving.


  1. Slow down our reactions

When alcohol is in your system, it affects how quickly you’re able to respond to different situations. Drinking slows your response time, which can increase the likelihood of an accident. Therefore, if the car in front of you brakes suddenly or a pedestrian crosses the street, it will take longer for your brain to process the situation and prevent an accident.


  1. Upset our sense of balance and coordination

Heavy drinking affects your motor skills such as eye, hand and foot coordination. Without crucial coordination skills, you may be unable to avoid an impending harmful situation. Some tell-tale signs of reduced coordination include trouble walking, swaying and an inability to stand straight. Too much alcohol can even make it difficult to get in your car and find the ignition.


  1. Impair our vision and hearing

Excessive alcohol consumption can negatively impact your vision. After drinking, you may notice that your vision is blurred or that you’re unable to control your eye movement. Impaired vision can affect how you judge the distance between your car and other vehicles on the road. Additionally, fewer objects may be visible within your peripheral vision, or what you can see to either side of you when looking straight ahead.


  1. Reduce our concentration and make us feel drowsy

Alcohol, no matter how much or how little, can influence your concentration. With driving, there are many things that require your undivided concentration, such as staying in your lane, monitoring your speed, being aware of other cars on the road, and obeying traffic signals. Your attention span is dramatically reduced with drinking, which significantly increases the chance of an accident.


A few stats from around the world


Drink-drive accidents still account for 14% of all road deaths in Britain. More young men die from drink driving than any other group of people.



Two hundred and fifty thousand people have died in alcohol related accidents in the past 10 years. Presently 25 000 people are killed each year in alcohol-related accidents. Five hundred people are killed each week in alcohol related accidents. Seventy-one people are killed each day in alcohol-related accidents. One American life is lost every 20 minutes in alcohol-related auto crashes. It is estimated that one out of every two Americans will be involved in an alcohol-related accident in his or her lifetime.


South Africa

Drunk driving is one of the biggest threats to road safety in South Africa. Research indicates that 50% of people who die on the roads have a blood alcohol concentration above 0.05 gram per 100 millilitres.


The more you drink, the more likely you are to have an accident

Alcohol can make you overestimate your own abilities and behave recklessly, such as thinking, ‘that road doesn’t look as busy’ or ‘that gap isn’t that big to jump over’. As blood alcohol concentration (BAC) rises, so does the risk of accidents. BAC, the amount of alcohol in your breath or blood, is measured in mg of alcohol per 100 ml of blood, or mg%. It’s affected by all kinds of factors, including:

  • how much alcohol you drink
  • how fast you drink it
  • your body size
  • how much you’ve eaten
  • your gender, and even
  • your emotional health.


Who is most at risk?

Alcohol consumption can put anyone at risk of causing an accident or other serious injury. However, some populations are more likely to get behind the wheel of a car after drinking. Drivers who are between the ages of 16 and 20 years’ old are 10 times more likely to be involved in a fatal crash, than drivers over the age of 21. While the number of underage drinking and driving cases has significantly decreased, many communities are pushing out new initiatives to keep adolescents safe.


The second highest alcohol-related crash risk includes individuals between the ages of 21 to 24. In 2012, 21 to 24-year-olds had the highest percentage of drivers in fatal crashes, with a BAC level of 0.08 per cent or higher – 32 per cent. Many of these cases involved binge drinking, a form of consuming too much alcohol in a short period of time. This often affects university students and young professionals who attend parties and other social events that have easy access to alcohol.









Topics: Driving safety, driver training, Driver safety



SAMTRAC International is the leading occupational health, safety and environment (HSE) management e-learning training course that provides students with the foundational and fundamental knowledge critical to occupational HSE management.

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