One pint of lager will have around 2.8 units, which will put you over the limit. One unit of alcohol leaves the body per hour
The old you can have a pint is back in the day when you was drinking 3% mild bitter, better to drink nothing and watch the next day if your a 7/8pint man cause you'll be over at 7/8 o'clock next morning
Tell your mate he's banned, 18months which will go down to 13 if he does the 3 day course, £300 fine and court fee's of about £180 and a mark on his licence for the next 11years before it comes off