Sunfish has raised some excellent points and there is many that are very similar..
lets say you are visiting a interstate airport in your private A/C on the weekend and forget a case or something..
after 2 beers at 0.03 you drive back to the airport and go retrive it with your dayglo vest, asic, staff card, aopa card and god knows what else.. and get tested..
you havent even got the keys to the plane..
no false positive here though..
if you work for Qantas during the week and your friendly contractor needs the numbers then you probably just lost your job !!
CASA dont seem to mind if you send your pissed passenger onto the tarmac (so long as the escort has an ASIC) just dont do it yourself....!