The UK’s drink-driving limit was originally set in 1967, when there were a lot less cars on the road and our attitudes towards road safety in general were a touch more liberal than they are nowadays, to put it mildly.

So is it right almost half a century later – and with millions more cars on our roads – that we should still be allowed to drive so long as we are under the 80mg per 100ml blood/alcohol limit?

Those in the “yes” camp will argue that they are still perfectly capable of driving with such a piffling amount of alcohol in their system. And unless the law is changed, it is perfectly acceptable to drive with two pints of beer or three small glasses of wine on board, correct?

Not necessarily, because defining exactly how much you can drink before being over the 80mg limit is far from an exact science. What’s more, the level of alcohol contained in the average pint of beer or glass of wine has increased significantly since the limit was introduced 47 years ago.