DRY January for drinkers could soon be pretty much compulsory all-year round for professional drivers in England and Wales as new drink-drive curbs in Northern Ireland leave us the booziest allowed at the wheel in the whole of Europe.

And road safety organisations like Brake and RoSPA want us to follow suit and cut drink-drive limits.

Our blood alcohol limit of 80mg alcohol per 100ml blood – read as 0.8 g/litre – for all drivers is shared only with Malta and Gibraltar.

Everyone else has lower limits, not only for the standard rate, usually the 50mg being adopted in Northern Ireland after being applied in Scotland for a year, but also lower and in four Eastern European countries it’s plain zero.

But then there are also different rates for professional drivers and novice drivers,  with ten countries – one in three – having zero rates for these drivers and most of the rest, like Northern Ireland’s new Bill, having a 20mg maximum.

And if you travel abroad you’ll find similar levels the world over.

What is the definition of a professional driver?

A spokesman for the Northern Ireland Assembly said a professional driver is not just those who need a professional certificate of competence, such as lorry, bus and taxi drivers, but “Anyone who drives for a living”.

So if you need a company car or van for work, that’s you too.

When will the new Northern Ireland laws apply?

Some elements of the Bill, which also introduces a new system of graduated licensing with novice drivers needing professional driving tuition followed by restrictions on carrying passengers and night time curfews, are not expected to be applied until 2018 because of the need for further consultation.

But the drink-drive laws are expected to be applied during this year, with roadside checks and a graduated penalty regime.

How can I stay within the legal limit?

The NHS says there’s no safe way to calculate how much alcohol you can drink to stay below the legal limit. Alcohol’s effect on the body varies between different people see its guidelines here, but including whether you’re male or female. And alcohol takes time to leave your body. Find out more about how long alcohol stays in your blood.

And what if you break the law?

Drink-driving is one of the most antisocial crimes and the penalties are severe, simply for being in charge of a motor vehicle while over the limit even if not driving, because the consequences of taking the wheel when unfit to drive can prove fatal.

For a start you will lose your licence, which for somebody who drives for a living means they lose their job, their way of earning a living, and potentially their whole career.

It is not like a speeding ticket – the stain on your criminal record remains for years, and can seriously affect other employment prospects too, and is consequently likely to impact on domestic family life.

You can also be jailed, and if someone is injured or killed the jail term can be up to 18 years with moves in hand to class a fatality as manslaughter rather than a motoring offence bringing a longer prison term.

This is in addition to the fact that any victims in your vehicle are likely to be close friends, family or loved ones.

European Transport Safety Council figures for European limits

These are the maximum drink driving limits across Europe for drivers as well as special limits for commercial and novice drivers where applicable. Shown in grammes per litre.