Portable Breath Test

Portable Breath Test

Law enforcement agencies in Washington State have used the Alcosensor III portable breath test device in DUI investigations. The Alcosensor III is produced by Intoximeters Inc., located in St. Louis, Missouri. The Alcosensor III is a hand held portable breath test device. Many refer to the hand held device as the portable breath test as the acronym for this test is PBT. However, it is legally referred to as the preliminary breath test in Washington State. WAC 448-15-010.

DUI Breath Evidence

Portable Breath Test

The purpose of the preliminary breath test is to assist a police officer in establishing probable cause before arresting an individual for DUI. The portable breath test is typically offered by the police officer after the Standardized Field Sobriety Tests or while the individual is still seated in their vehicle. The portable breath test is strictly voluntary and there are no consequences in refusing this portable breath test in Washington State. In fact, the Police Officer must provide these warnings before administering the preliminary breath test:

1. This breath test is voluntary;
2. It is not an alternative to an evidential breath alcohol test as described in chapter 448-13 WAC.

WAC 448-15-030.

Most criminal courts in Washington State do not find this evidence admissible. However, many Department of Licensing hearing examiners will admit portable breath test evidence during the civil administrative hearing. To be deemed admissible the Police Officer must administer the portable breath test according to procedures.

Portable Breath Test Procedures

These procedures are:

1. The operator must determine by observation or inquiry if the suspect has consumed intoxicants within the previous 15 minutes before providing a breath sample;
2. The operator must check the temperature of the device;
3. The operator will press the "read" button to secure a sample of the ambient air and the result of that air must read 0.003 or less.
4. Then the suspect provides a breath sample.

WAC 448-15-030.

Alcosensor III

The Alcosensor III employs fuel cell technology which detects alcohol and not acetone or other substances commonly found in the breath. The fuel cell is a porous disk saturated with an electrolyte and mounted in a valve assembly. The Alcosensor III receives a fixed volume sample over the surface of the fuel cell. Alcohol that contacts the fuel cell surface is chemically analyzed. Each alcohol molecule analyzed frees electrons during the process. The amount of measured electrons produces a digital Breath Alcohol Concentration that is reported in the three digit display screen.

The Alcosensor III units do require regular maintenance and calibration. Calibrations should be conducted with an approved wet bath simulator or a dry gas standard. Other PBT brands include the AlcoHawk, AlcoMate, SafeWay and AlcAlert which are popular consumer devices.

1001 Fourth Avenue, Suite 2388
Seattle, Washington 98154