whether its reasonsable or not depends on why the levels where set as they were, and wheteher the other occupations need to be able to operate without the level of impairment that goes with that BAC. Engineers are subject to the same legislation, but thier BAC max limit is the same as for drivers. That said Whether reasonable or not, I would agree that they should be the same for all workers at an airport.
You may have a 'feeling' that police would protect thier own' thats all its is a feeling. I can tell you from the other side of the coin, they wont, not in this day and age when being on the same planet as someone who has committed a offence is grounds for hanging, and Police Discipline boards operate on the 'march in the guilty b******d' system of justice.