Will a saliva alcohol test work if I have a very dry mouth?

By John Hawes | Last updated: January 16, 2019

When used in a screening test, only a small sample amount is needed to conduct the saliva alcohol test. However, if you have a very dry mouth, it is possible that you will be unable to produce an adequate sample. In that case, an alternative testing method such as a breath or urine test may be used.

Use of Saliva-based Alcohol Screening Devices (ASD)

The Department of Transportation (DOT) requires alcohol and drug testing of all transportation employees who hold safety sensitive jobs. DOT guidelines provide a list of approved testing devices for use when an employee subject to DOT rules is tested. Different tests and testing methods are approved for drug and alcohol screening tests and confirmation tests. Several different brands of saliva alcohol tests are approved for DOT alcohol screening tests. Employers or agencies not subject to the Department of Transportation's guidelines may use the DOT approved saliva alcohol screening tests or similar ones for alcohol screening.

Varying Collection and Sample Requirements

Most saliva alcohol tests require you to either saturate an absorbent swab with saliva or produce a forced expectorant (spit) sample for analysis. The exact amount of saliva that you will need to provide for your test will be determined by thetesting device used. For instance, the manufacturer of the Alco-Screen saliva alcohol test indicates that it may be used even with test subjects who have dry mouth. Other devices may require more saliva to render accurate results. In some instances, having a dry mouth may mean that it takes longer to collect a sufficient saliva sample but a saliva alcohol test is still possible. Sometimes an adequate sample cannot be produced, and the saliva test cannot be performed. Each testing device will have an indicator that communicates whether or not your saliva sample is sufficient to produce a valid test result.

Procedure Following Invalid Sample

If you are unable to produce a sufficient saliva sample, you may be asked to make a second attempt before an alternate testing method is sought. Your test administrator should make note of your condition and the attempts to provide a sample on your alcohol testing form. Under Department of Transportation guidelines, if you cannot provide a sample for the saliva alcohol test, the breath alcohol technician will use an evidential breath testing device instead. If you are unable to test using either the saliva alcohol test or the evidential breath testing device, you will be required to obtain proof of an relevant medical condition or your failure will be deemed a refusal to test.

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Workplace Testing 101 Alcohol Testing Oral Fluid Testing Health and Safety Lab Test Pre-work Evaluations

Written by John Hawes

Profile Picture of John Hawes

John Hawes is the CCO and co-founder at SureHire Occupational Health Testing. John graduated in 2001 from the University of Alberta with a Bachelor of Science degree in physical therapy. As a former physical therapist, John uses his knowledge of physical therapy and interest in ergonomics and biomechanics to devise fit for work testing.

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