Testing for Intoxication

Breath Testing A device for measuring the alcohol content

of alveolar breath. Rapid and accurate results

Breath-Test instruments Breathalyzer developed in 1954 Breathalyzer has been phased out and

replaced Ratio of alcohol in the blood to alcohol in

alveolar breath is 2100 to 1 Infrared and fuel cell detectors

No chemicals Microprocessor controlled

Considerations in Breath Testing Unit is programmed to accept no less then 1.1 –

1.5 liters of breath

Blow for a minimum time at a minimum rate Slope detector – ensures that the breath sample

is alveolar or deep-lung breath Mouth alcohol – from vomiting, belching, or recent

intake of an alcoholic beverage, or alcohol containing mouthwash

Nothing can be in the person’s mouth 15-20 minutes before testing

Analysis of Blood Alcohol Blood is drawn using a non-alcohol disinfectant Sealed in an airtight container Add anticoagulant – keeps blood from clotting Add preservative – inhibits the growth of

microorganisms Must be kept cold to keep alcohol level from

dropping Must be stored for only a short period of time

Collecting blood postmortem Collect a number of blood samples from

different body sites All the blood alcohol levels should be the

same Collect urine and vitreous humor as well

because they do not suffer from postmortem ethyl alcohol production

Alcohol and the Law Current blood-concentration standard for

intoxication is 0.08 Per se laws – any individual exceeding a defined

blood-alcohol level 0.08 shall be deemed intoxicated

Implied consent law – prevent a person from refusing to take a test on constitutional grounds. Must consent to a test for alcohol intoxication or lose their license.