Click on any of the areas in yellow for an explanation of what it means.

BAC TICKET EXPLAINED
By Attorney Craig Cahoon

SIM TEMP 34C +/- .2c

This section refers to the External Standard Simulator Solution temperature.  The BAC machine consists of a large plastic box with a breath tube coming out of it and a smaller glass beaker filled with a clear looking liquid.  This clear liquid is a mixture of alcohol and water, that when heated to a known temperature  produces a know amount of alcohol vapor.  According to Washington State Law, that "know temperature" must be 34 degrees Celsius plus or minus .2 degrees Celsius.  Oddly enough, this temperature must be put in manually to the BAC machine by the operator.

OBSERVATION BEGAN

The Washington Administrative Code requires a 15 minute observation period before a valid breath sample can be given.  This is to ensure that no alcohol is left in the mouth.  Mouth alcohol can come from recently consuming alcohol but it can also come from burping, vomiting, etc.  The BAC machine will not allow a subject sample to be give until more that 15 minutes have elapsed from the observation time.

CITATION NUMBER

This refers to the number on the citation (or ticket) the officer is planning on giving you for the Driving Under the Influence charge.

OPERATOR'S NAME

This is the person operating the BAC machine; most likely the same officer that will issue you a ticket for DUI.

SUBJECT'S NAME

This is your name.

SUBJECT'S DOB

Your Date of Birth.

EXTERNAL STANDARD BATCH #:

This refers to the External Standard Simulator Solution.  The clear looking liquid (alcohol and water mixture) in the  External Standard Simulator is mixed together in batches by employees at the State Toxicologist's office.  Each batch must be certified to contain the right amount of alcohol and water and when it was mixed.  Each batch is only good for a certain amount of time.  By looking up the Batch Number on the State Patrol Web Site, you can determine if there is a certificate on file and whether or not the batch is still within date.

The result of this test must be between .072 and .088 (inclusive), otherwise the test will be invalid.

BLANK TEST

The BAC machine tests the ambient air for the presence of alcohol vapor four times during the breath testing process.  This is to ensure that the two Subject Samples are not contaminated from an outside source. 

BLANK TEST TIME

All times are recorded in military format.  A reading of 14:35 translates to 2:35 pm.

INTERNAL STANDARD

As a part of the Breath Test cycle performed by the BAC machine, it performs an internal standard test.  This test does not involve the use of alcohol, but does check that nothing unusual is inside the breath test machine.  See "How the BAC machine works" for more detail. 

SUBJECT SAMPLE #1

This is the first time you blow into the BAC machine.  The machine disregards the first portion of your breath and tries to test only the bottom 10% of your expelled air.  This is because the closest relationship between the amount of alcohol in your blood and the amount in your breath is contained in the last 10% of your breath.

EXTERNAL STANDARD

Here, the BAC machine pulls alcohol vapor from the External Standard Simulator.  The results must be between .072 and .088 (inclusive).   Interestingly, the machine bypasses the breath test tube entirely during this part of the test.

SUBJECT SAMPLE #2

This is your final blow into the machine.  A breath test that does not contain two subject samples is invalid.  You may notice that the amounts of alcohol listed on the two subject samples is different.  The variance most likely comes from a difference in the amount of air you were able to blow into the machine during your two samples.  If the two samples differ by more than 10% of their mean (or average) then the result is invalid.