BREATHALYZER

Breath·a·lyz·er   (brěth'ə-lī'zər)    A trademark used for a device that detects and measures alcohol in expired air so as to determine the concentration of alcohol in a person's blood.

Main Entry: Breath·a·ly·zer
Pronunciation: 'bre-th&-"lI-z&r
Function: trademark
—used for a device that is used to determine the alcohol content of a breath sample

Main Entry: Breath·a·ly·zer
Pronunciation: 'breth-&-"lI-z&r
Function: trademark
—used for a device consisting of a small tube ofchemically sensitized crystals connected to a balloon that is used to determine the alcohol content of a breath sample

breathalyzer

device used by police to determine the amount of alcohol in the system of persons suspected of being intoxicated. In the analyzer, a precise amount of the suspect's exhaled breath is passed through a solution of potassium dichromate and sulfuric acid; the change in the colour of the solution is proportional to the amount of alcohol in the air sample, which, in turn, is directly related to the alcohol content of the blood. Driving ability is seriously impaired when the alcohol concentration in the blood exceeds 80 milligrams per 100 millilitres.

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