Breathalyser

A breathalyzer or breathalyser (a portmanteau of breath and analyzer/analyser) is a device for estimating blood alcohol content (BAC) from a breath sample. Breathalyzer is the brand name (a genericized trademark) for the instrument that tests the alcohol level developed by inventor Robert Frank Borkenstein. It was registered as a trademark on May 13, 1954, but many people use the term to refer to any generic device for estimating blood alcohol content .

A 1927 paper produced by Emil Bogen, who collected air in a football bladder and then tested this air for traces of alcohol, discovered that the alcohol content of 2 litres of expired air was a little greater than that of 1 cc of urine. However, research into the possibilities of using breath to test for alcohol in a person's body dates as far back as 1874, when Francis E. Anstie made the observation that small amounts of alcohol were excreted in breath.

Also, in 1927 a Chicago chemist, William Duncan McNally, invented a breathalyzer in which the breath moving through chemicals in water would change color. One use for his invention was for housewives to test whether their husbands had been drinking.

In late 1927, in a case in Marlborough, England, a Dr. Gorsky, Police Surgeon, asked a suspect to inflate a football bladder with his breath. Since the 2 liters of the man's breath contained 1.5 ml of ethanol, Dr. Gorsky testified before the court that the defendant was "50% drunk".

In 1931 the first practical roadside breath-testing device was the drunkometer developed by Rolla Neil Harger of the Indiana University School of Medicine. The drunkometer collected a motorist's breath sample directly into a balloon inside the machine. The breath sample was then pumped through an acidified potassium permanganate solution. If there was alcohol in the breath sample, the solution changed color. The greater the color change, the more alcohol there was present in the breath. The drunkometer was manufactured and sold by Stephenson Corporation of Red Bank, New Jersey.

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