What Is a Breathalyzers and How Does It Work?
The first Breathalyzer included a mouthpiece and two liquid-filled chambers that were coupled to a metre that detected a colour change. The subject exhales via the mouthpiece into a test chamber filled with a reddish-orange potassium dichromate solution to utilise the Breathalyzers (K2Cr2O7).
Alcohol combines with the reddish-orange potassium dichromate solution in the Breathalyzer and turns green. The amount of alcohol in the exhaled air is proportional to the degree of colour change.
A photocell examines the colour differences between the reacted mixture in the test chamber and an unreacted mixture in the reference chamber. The colour difference generates an electrical current, which can be translated into a quantitative BAC value.
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