Arizona Drunk Driving Testing in Arizona

In Phoenix and elsewhere throughout Arizona and the United States, drunk driving has claimed thousands of lives. Deaths caused by drunk driving are needless and entirely preventable, and testing for drunk drivers on the road has become a necessity. Although many are against the methods of testing, as long as drunk driving continues, driver testing will be a necessity. Yet regardless of this necessity, DUI testing must verifiable, reliable and fair.

If you would like to discuss your specific case or hire legal representation, please contact a Phoenix and Arizona drunk driving attorney at the Montano Arentz & Associates, PLLC to schedule a free consultation.

The History of Drunk Driving Testing

Alcohol intoxication is legally defined by the blood alcohol concentration level in a person at any given time. However, taking a blood sample in the field for later analysis in the laboratory was not practical or efficient for detaining drivers suspected of driving under the influence (DUI). What was needed was a way to measure something related to BAC without invading a suspect’s body.

Urine tests for alcohol proved to be just as impractical in the field as blood sampling. In the 1940s, breath alcohol testing devices were first developed for use by police. In 1954, Dr. Robert Borkenstein of the Indiana State Police invented the Breathalyzer, one type of breath alcohol testing device used by law enforcement agencies today.

If you have questions about the Breathalyzer, DUI, or wish to discuss your case, please contact the Phoenix and Tucson area drunk driving attorneys with the Montano Arentz & Associates, PLLC

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Principle of Testing for Drunk Driving

When a person drinks alcohol, the alcohol is absorbed by the mouth, throat, stomach and intestines into the bloodstream. Absorption of alcohol is not the same as digestion of alcohol, and absorption does not chemically change the alcohol that enters the bloodstream in this way.

As this alcohol-laced blood circulates through the lungs, some of the alcohol moves across the membranes of the lung’s air sacs (alveoli) and evaporates into the air in the lungs, called the alveolar air. The concentration of the alcohol in the alveolar air is proportionally related to the concentration of the alcohol in the blood. As the alcohol in the alveolar air is exhaled, it can be detected by the breath alcohol-testing device. So instead of having to draw a driver’s blood to test his/her blood alcohol level, an officer can test the breath on the spot and determine whether there is a reason to arrest the driver for drunk driving.

Because the alcohol concentration in the breath is related to that in the blood, it is possible to calculate the BAC by measuring alcohol in the breath. The ratio of breath to blood alcohol is 2,100 to 1. This means that 2,100 milliliters of alveolar air will contain the same amount of alcohol as 1 milliliter of blood. The mechanisms used to measure a persons blood alcohol level in this way are not foolproof however, and sometimes a Phoenix or Arizona drunk driving attorney is successful arguing against this test in certain cases.

The legal standard for drunk driving across the United States was 0.10% for years, but recently many states have adopted the 0.08% standard either on their own or at the urging of the federal government. The standard 0.08% means that there is 0.08% gram of alcohol per 100 milliliters of blood. The American Medical Association states that a person can become impaired when the blood alcohol level hits 0.05%.

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Types of Testing Devices

There are three major types of breath alcohol testing devices based upon different principles:

A Breathalyzer uses a chemical reaction involving alcohol that produces a color change.

An Intoxilyzer detects alcohol by infrared (IR) spectroscopy.

The Alcosensor III or IV detects a chemical reaction of alcohol in a fuel cell.

Each device has a mouthpiece or tube through which the drunk driving suspect can blow air and a sample chamber where the air goes. The rest of the device will vary depending on the type used.

Each device has its own weaknesses, and a Phoenix and Tucson area drunk driving attorney may be able to use these weaknesses to your advantage. If you are arrested for drunk driving, please contact the attorneys with the Montano Arentz & Associates, PLLC

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Blood Alcohol Level charts

The following are blood alcohol level charts for your information. Please note one drink is equal to either:

• One 12 oz. Light Beer with an alcohol concentration of .042%
• 1 oz. of 80 proof liquor or 1 oz. of 100 proof liquor
• A 3 to 5 oz. glass of wine

Blood Alcohol Concentration Chart for Males

Alcohol % in bloodstream for weight (lbs.) and number of drinks

Blood Alcohol Concentration Chart for Females

Alcohol % in bloodstream for weight (lbs.) and number of drinks

If you have been arrested or cited for drunk driving, please seek the assistance of a Phoenix and Arizona attorneys at the Montano Arentz & Associates, PLLC or another experienced attorney.

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DISCLAIMER: Montano Arentz & Associates, PLLC and Phillips Law Group, P.C. are separate, independent law firms from other firms listed on this website. Phillips Law Group, P.C. handles only contingency fee cases. This includes automobile and vehicle accidents and all personal injury cases. We also handle medical malpractice, product liability, employment, wage and hour cases, Social Security disability, and workers’ compensation cases. Montano Arentz & Associates, PLLC handles criminal and DUI cases, as well as consumer bankruptcy and debt relief cases.