The Federal Motor Carrier Safety Administration (FMCSA) sets strict rules for commercial drivers regarding drug use. Taking prescription medications or illicit drugs that could impair a driver’s ability to drive safely is not allowed. To ensure drivers remain compliant with these rules, every individual must submit to drug testing pre-employment, post-accident, when an employer has reasonable suspicion they are using, or during random testing. Drug testing is also part of the return-to-work protocol and follow-up procedures when a driver tests positive, refuses testing, or otherwise fails to follow standard procedure and obtain a negative result.
Why are the requirements for drug testing so strict? Despite the known dangers of driving impaired, drug use is still a leading factor in many truck-involved accidents. The National Transportation Safety Board (NTSB) and the National Institute on Drug Abuse performed a joint review of trucking accidents in eight states, covering a one-year period. Of the 168 drivers who died in the accidents, 67% of them had detectable levels of drugs in their blood, and 33% tested positive for psychoactive drugs or alcohol.1
Regular planned and random drug testing helps keep operators honest and sober on and off the job. While there are many ways to test for drugs, including collecting saliva, hair, blood, and urine samples, choosing the right test is critical. The DOT does not recognize test results for every specimen type.
We’ll walk you through the options and discuss the pros and cons of each testing sample type so you can choose the best test.
Urine Drug Testing
Drug testing using a urine sample has been the gold standard of the trucking industry since the early 90s. It is a simple, non-invasive way to determine whether an individual is taking or using drugs that could impair their ability to drive.
The process is well-established because urine testing has been the preferred drug testing method for many years. Testing facility employees complete certified urine specimen collector training to master collection protocols, processing procedures, and testing techniques to comply with DOT regulations. Split specimen collection, in which labs keep a backup sample for confirmation testing, further enhances testing accuracy. When testing facilities follow DOT-standardized protocols, testing results are highly accurate and reliable.
Even under the ideal conditions, urine drug tests are not perfect. Urine samples are susceptible to tampering. Individuals hoping to fly undetected under the radar may try to switch out samples or dilute them by drinking excessive amounts of water. While specimen collectors can thwart these attempts by supervising specimen collection, doing so invades the driver’s privacy.
Urine tests also have detection limitations. They can only detect drug use within the past few days. If a driver has not used drugs during that time period, their test is likely to come back clean. Still, this day-long window is better than some other testing methods and long enough to detect drug use in many cases. Testing facilities must test samples within the prescribed temperature range and timeframe to ensure results are valid.
Oral Fluid Drug Testing
In 2022, the Department of Transportation (DOT) proposed changing drug testing rules to allow for testing using a saliva sample. Satisfied that testing was both accurate and defensible, oral fluid testing became allowable in May 2023. However, this type of testing remains largely untapped.
Oral fluid testing is only a viable option if split testing is available. Two samples must be available to test, and two testing facilities must be certified to test them. Thus, a second lab can verify the results of the first test by testing the second sample. However, drug testing using a saliva sample remains inaccessible to most drivers without two certified testing facilities.
Why pursue oral fluid testing? Because it is simple and less invasive than urine drug tests, overcoming some of the challenges with urine drug tests.
- Saliva samples are simple to produce and collect
- All samples are easily observed
- No invasion of patient privacy
- Minimal opportunities for sample tampering
- Drivers can give samples on-site without the need for special facilities
This straightforward sample collection method makes oral fluid tests quick and easy to collect.
While the detection window for many substances varies, urine drug tests can usually detect drug use within the preceding few days. Oral fluid tests may only detect drug use within the past 24-48 hours. However, they have proven more effective at detecting cannabis consumption than urine tests, detecting THC for up to 72 hours in chronic users. However, some drugs show up in lower concentrations in saliva, making them more difficult to detect. Thus, oral fluid tests may miss evidence of infrequent or past drug use.
Alternative Tests
In addition to urine and saliva drug testing, labs can test for drug use using blood or hair samples. These are excellent options that provide unique benefits and insights into an individual’s current or past drug use. For example, hair testing can detect drug usage within the past 90 days, which can reveal chronic problems with drug use. Blood testing is extremely accurate and can easily detect active impairment that may not show up yet in saliva or urine. However, neither of these testing methods is approved by the DOT.
The Best Test
Until at least two labs become certified in saliva drug testing, the best and only option for remaining compliant with DOT drug testing requirements is to complete urine drug testing. While they are not required as part of routine CDL medical exams, you may require drivers to complete testing when you hire them or any time you suspect they are using on the job.
The DOT and FMCSA take drug use seriously because zero-tolerance keeps everyone on the road safe, including your drivers.
1https://pubmed.ncbi.nlm.nih.gov/8263478/
