Alcohol sensor an invasion of privacy?

Police in Florida (and elsewhere, I am sure) are adding to their arsenal against drinking and driving by deploying something called a Passive Alcohol Sensor. It looks like an ordinary flashlight, but it sucks in a sample of the air where it is pointed and analyses it for the presence of alcohol. Some are calling it an invasion of privacy while others say it is just an extension of a police officer's nose.

See some coverage from NBC-2 from Southwest Florida: NBC2 News Online - Alcohol sensor an invasion of privacy?. There's also a link to video of the story.

The Passive Alcohol Sensor is made by PAS International, which describes the technology thusly:

PAS IV:

The P.A.S. IV Alcohol Screening System combines: a) high-intensity, super-beam flashlight technology with b) a dynamic sampling system and c) a miniature alcohol sensor. It “sniffs” ambient air, the breath, open containers, or enclosed spaces for the presence of alcohol. The P.A.S. functions as a non-intrusive “extension of the operator’s nose.

The P.A.S. is a hand-held, rapid alcohol detection instrument using a platinum electrochemical fuel cell sensor of high alcohol specificity, accuracy and stability. Designed for law enforcement, industry, corrections, transportation agencies, and educational facilities. The operator-controlled sampling system guarantees accurate detection of alcohol, and is especially suited for quick subsequent measurements.

The P.A.S. is used to check alcohol presence/absence with or without a subject’s direct participation. When used without the subject’s direct participation it is known as passive sampling, as opposed to active testing where the subject blows directly into a mouthpiece or the intake port. The P.A.S. can also be used to detect open containers of alcoholic beverages, or to detect low, ambient levels of alcohol in enclosed spaces such as vehicles, jail cells, or classrooms.