apparently. i never had it on long enough to apply. well i did, technically, but i sent them the paperwork showing the removal and never heard anything back so.....

I wonder if you could blow compressed air into it. :question:

no, it has a vibration switch in it. you blow normal for 3 seconds then hum into it for the next 3 seconds. i used to joke that i had to give my truck a hummer before it'd go anywhere :p

There are "features" on the device to keep you from doing stuff like that, or having someone else blow into it for you.

how can it know if someone else is blowing into it?

this was my car, the guy who ran into my windshield was completely drunk.
i had no alcohol that night, so i was driving, this other guy was not driving, but had been drinking too much.

he is ok now. well, not O K, but lives.

was he on a motorcycle? no, there would only be pieces left. bicycle or really poor walking abilities?

he was trying to cross the street, which in fact is an avenue, running.
he never saw me. nor me.

Many of the ones that require humming are tuned. To you.

I haven't found documentation of such, but I also wouldn't be surprised that in addition to BAL there's something in the beastie to test humidity and or temperature of the blow, to keep people from doing the compressed air thing.

huh < scratches head \> maybe, but with the company i used they said that if i took my car to the mechanic and joe mechanic was hungover and caused me to register then to bring the reciept in for proof. not trying to disqualify your statement, just maybe that particular company doesn't have that feature yet......