I have always been told that we are all different, and that we all have different tolerances to everything we eat or drink, including alcohol. So, to me, the breathalyzer is yet another piece of useless technology. Back in the day if a Police Officer said your words were slurred, you had difficulty maintaining balance and you eyes were glazed, you were guilty. It made no difference how much you had drunk. I do not claim to be knowledgeable about this, but it seems to me that if I drink two pints, and a lady of 5' 3" weighing 8stone drinks two pints, I would show a much lower alcohol content as it would be more diluted. Yet that was the advice of the day.
The fail level on a Breathalyser is so high at that level everyone that fails will be well beyond safe driving levels.
I remember reading some research done by or for the military, on impairment due to different levels of alcohol, and the outcome was, when there was a measurable levels of alcohol in the blood the subject was showing signs of impairment but that would have been in the 50's to 60's, I would expect we can measure much lower levels now.
I remember showing that to a friend who was a drink driver, though not yet caught or crashed (he did crash in the end) his response was, "well they would say that wouldn't they"
When he did crash, and mentioned he had had a few, there was a lot of sympathy, the the idea was something along the lines of, 'cars are tricky things with a few drinks in but then bike's were worse'. How times have changed!
