Drink-driving limits – do you know what they really mean?

Posted: 16/12/2015

Now that the festive season is upon us, the temptation of drink-driving looms large again. But how many of us really know what the legal limits are for safe driving?

In England, Wales and Northern Ireland, the legal limit for drivers is: 80 milligrams of alcohol for every 100 millilitres of blood in your body; 35 micrograms of alcohol for every 100 millilitres of breath; and 107 milligrams alcohol for every 100 millilitres of urine. Scotland has lower limits of 50 milligrams per 100 millilitres of blood and 22 micrograms per 100 millilitres of breath. 

Years of campaigning by road safety organisation such as Think! and Road Safety GB have increased awareness extensively and have led to significant decreases in the number of drink-drive incidents, with figures falling from 20,000 in 1979 to around 6,000 last year. Although this is a big improvement, there is still work to be done.

Recently, Think! has launched its latest campaign, with the headline message that a second drink can double your chances of being involved in a fatal road accident. This message follows their latest research which revealed that one in 10 people would still consider driving after two or more drinks, rising to one in five 18 to 34 year old men.

The focus on the number of drinks would seem a beneficial approach as recent research by the Accident Advice Helpline revealed that, in a survey of 1,000 motorists, less than 20% of those surveyed could correctly identify the drink drive limits. The survey did, however, show a worrying conception that one drink of any kind was acceptable. An example of a ‘safe’ drink was a Long Island ice tea, which would typically contain four to five shots of hard spirits. Of those surveyed, 15% thought that it would be acceptable to drive after having one of these cocktails.

The difficulty is that alcohol affects people in different ways due to a number of physiological factors. So it is hard to state definitively what will put someone over the limit. Some people mistakenly think that they are safe to drive if they do not feel drunk. 

For these reasons, the safest and clearest message – and one that a number of campaigners are calling for - is a zero tolerance message as this is the only way to be 100% sure. The Accident Advice Helpline survey found that this position was supported by 44% of those surveyed. As a minimum, however, 73% of those surveyed thought that the drink drive limit should be reduced from the current level, which is the highest in Europe. But this position was not supported by a recent survey by SmartWitness in which 62% of respondents did not support extending the lower limit imposed in Scotland on the rest of the UK’s roads.   

William Broadbent of the Penningtons Manches personal injury team commented: “While it is good to see a new campaign promoting awareness of the risks of drink-driving, it is worrying that the message isn’t necessarily being taken on board by all drivers and more concerning still that, although drivers may know what the limits are in theory, they don’t know how they translate into reality.

“We deal with cases every day of people who have been seriously injured or killed as a result of drink-driving. While the number of such accidents is decreasing, the rate of decrease is slowing. Even the message that a second drink can double the chances of an accident is problematic as people may think that it is acceptable to have one drink and then get behind the wheel. A zero tolerance message can be the only solution, potentially with legislation to support enforcement.”

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