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Preliminary Alcohol Screening

A Preliminary Alcohol Screening device or PAS device is a portable breath tester used by law enforcement officers including members of the California Highway Patrol (CHP), San Francisco Police Officers, San Francisco Sheriff's Deputies or Federal National Park Service Police Officers. The most common PAS device used in California DUI investigations is the Alco Sensor IV manufactured by Intoximeters Inc.

The Alco Sensor IV (ASIV) is a handheld breath Preliminary Alcohol Screening (PAS) device used to measure a motorist's breath alcohol level at the scene of a traffic stop which has resulted in a DUI investigation. The device provides a method of determining a subject's breath alcohol concentration with some degree of accuracy. California law requires breath tests to be conducted in compliance with California Code of Regulations. Title 17 is the governing section of the California Code of Regulations applicable to alcohol breath tests. One important provision of Title 17 is that the person blowing into the PAS device be observed for fifteen (15) minutes prior to submitting a breath sample to remove mouth alcohol which may be present. Another important provision of Title 17 is that two breath samples must be collected.

The manufacturer of the Alcosensor IV, Intoximeters, Inc. manufacturers portable and stationary alcohol breath testing machines which indirectly determine the amount of alcohol in a person's blood. In additional to manufacturing the devices, Intoximeters offers training on the maintenance of the devices. Intoximeters, Inc. is based in St Louis, Missouri. However, members of the California Highway Patrol receive training in PAS devices at the CHP Academy located in Sacramento. Local law enforcement officers either receive training at their respective academies, in service training or no training at all.

PAS Coordinator

Preliminary Alcohol Screening devices are maintained by a law enforcement officer who is designated as the PAS Coordinator. The PAS Coordinator is charged with testing the accuracy of the PAS devices utilizing a wet bath simulator which heats alcohol in solution to a specific temperature. Once heated to 34 degrees celsius, the vapor from the solution is blown through the PAS device and the value is recorded on an accuracy check log. The PAS Coordinator may then adjust the PAS device to report the expected value if it is out of calibration.

As well, the PAS Coordinator is required to send damaged or malfunctioning PAS devices to the factory for service or repair. Any service or repair must be documented and the records must be retained for production when ordered by the court, the Department of Motor Vehicles, or an attorney who represents a person accused of driving under the influence. Intoximeters, Inc. was founded by Dr. Glenn Forrester in 1945. Dr. Forrester had been working for some years prior to 1945 on a process to capture alcohol from a breath sample. When Intoximeters, Inc. was founded, Dr. Forrester had already manufactured his first portable device used in collecting evidence for DUI investigations.

Alco Sensor

The early versions of the Alco Sensor were introduced in the 1970's. This device was a hand held portable alcohol screening device which was a new addition the normal equipment police officers use. The Alco Sensor product line is presently in production and is one of the most widely used alcohol screening devices available. They are commonly reffered to as Preliminary Alcohol Screening devices or PAS devices.

In the 1990's, Intoximeters Inc. began to manufacture the Alco Sensor IV. The Alco Sensor IV utilizes fuel cell technology integrated into the device. That integration is used to determine the alcohol concentration from a person's breath. The Alco Sensor IV is available with or without a memory option. The memory option allows the device to electronically store the data which can then be transferred to a computer. To date, the Alco Sensor IV is one of the most widely used breath detection devices and comes in a Black Dot, Green Dot and Red Dot models. The Black Dot model is utilized by law enforcement.

Alco Sensor IV software follows a specific test protocol. Each step in the protocol is displayed on an LED display, providing the operator with step-by-step instructions for administering a breath alcohol test. The device automatically samples deep lung breath and is programmed to display the result in a three digit readout in California (two or four digits where required). Inserting the plastic mouthpiece turns the instrument ON and depressing the release button which ejects the mouthpiece turns the instrument OFF.

Law Governing Preliminary Alcohol Screening (PAS) Devices

There are specific legal rules which govern admissibility of results obtained on the Alco Sensor IV Preliminary Alcohol Screening device. Alcohol breath testing is governed in the State of California by Title 17 of the California Code of Regulations. Additionally, California appellate court decisions control foundational issues which must be satisfied prior to admitting the numerical result from a Preliminary Alcohol Screening device.

In 1976, the California Court of Appeal decided People v. Adams , while in 2002, the California Supreme Court decided People v. Williams . These cases stand for the general proposition that before the numerical value may be admitted, the proponent (usually the prosecution or California Department of Motor Vehicles) must establish: 1) the particular PAS was in working order; 2) the test was properly administered; and 3) the operator was competent and qualified to administer the test.

Alco Sensor IV Warranty

Intoximeters Inc., limits the warranty on the Alco Sensor IV to a period of twelve (12) months from the original invoice date.

California PAS Devices

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