Research by Direct Line Car Insurance exposes the risk of driving over the legal alcohol limit due to a lack of understanding of alcohol measures, which sees people pour excessively large glasses containing several units of alcohol. In a practical experiment testing drivers’ ability to pour set limits of alcohol, 56 per cent of participants over poured when asked to fill a glass with standard pub measures of wine.
The experiment tested 100 drivers’ ability to free pour pub standard measures of alcohol, investigating whether when drinking at home or at someone else’s home within their support bubble, or in someone’s garden for those in lower tiers, drivers could be over the legal alcohol limit without realising.
Over half (51 per cent) of participants poured more than 125ml when asked to fill a glass with this measure, 13 per cent poured at least a 175ml sized glass and one in 20 poured over 200ml. When asked to pour out a 175ml glass, nearly two thirds (62 per cent) over poured and 14 per cent poured the equivalent of at least a 250ml glass of wine containing a minimum of 3.2 units of alcohol.
Spirits are even tougher to estimate, with three quarters (75 per cent) of participants over pouring a single 25ml spirit measure and one in six (18 per cent) pouring at least a double (50ml) instead of a single. When asked to pour a double, nearly two thirds (63 per cent) poured more than the correct 50ml of spirits. Almost a quarter (24 per cent) poured at least a treble (75ml) and one in 12 (eight per cent) went so far they poured 100ml, a quadruple measure. Pouring spirits over ice led to a greater proportion of participants overpouring both a single (77 per cent) and a double (64 per cent) measure.
The average size of a home measure is much greater than a standard pub or restaurant measure. However, the average volume of a glass of wine a person pours for themselves at home is 190ml, with men pouring slightly more (200ml) than women (180ml). Nearly a fifth (18 per cent) of drivers when having a glass of wine pour at least 250ml, equivalent to a third of a bottle of wine. The average home spirit measure is 62ml, which is more alcohol than if ordering a double in a bar or restaurant, while for a quarter of people (25 per cent) their homemade G&T would include at least a treble measure of gin (75ml).
Drink driving risks
Of motorists who drink alcohol and drive, nearly one in five (18 per cent) would drink alcohol if they were the designated driver. One in nine (11 per cent) insist on pouring their own measures but three million motorists (seven per cent) would allow others to do it for them. As the experiment revealed these drivers could find themselves over the drink drive limit without realising.
When asked nearly five million (14 per cent) motorists admit to having driven their car when they thought they were over the limit in the previous six months, with over two million (six per cent) believing this to be because the person serving them poured larger drinks than they realised.
There is widespread confusion about the legal limit for consuming alcohol and driving across the UK. Just four per cent of drivers in Scotland and just 12 per cent of drivers living in England, Wales or Northern Ireland know what the legal limit is for where they live. The drink driving limit in England, Wales and Northern Ireland is 35 micrograms of alcohol per 100 millilitres of breath, while in Scotland it is just 22 micrograms of alcohol per 100 millilitres.
Simon Henrick at Direct Line commented: “This research is a warning to anyone planning to visit someone else’s home over the New Year period, as even one glass of home poured alcohol could push someone over the limit. It isn’t just the safety of the driver and passengers in their car that are at risk if a driver is over the limit, it is everyone else on the road too.
“Due to the impact of Covid-19 more people will be drinking at home this New Year than any other. If a driver chooses to have a drink at home or at someone else’s house within their ‘bubble’ or in someone else’s garden for those in lower tiers and then drive, it is vital they know how much alcohol they are consuming, before getting behind the wheel. The only way anyone can be sure that they are safe to drive in this situation, is if they don’t have any alcohol at all.”