I can remember when the new UK regulations came in around 14 years ago, in very broad layman's terms, the limit for driving a car was/is about 2 pints of ordinary bitter (3.8% OG). The limit for flying an aeroplane was the equivalent of 1/2 of a pint of ordinary bitter. In other words, not a lot. Air Trafficers were also subject to the latter limit.
However, LAMEs (engineers) only had to meet the car driving limit. I could never quite understand that for engineers can also cause a modicum of aviation mayhem.