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Human Resources Department

Occupational Safety & Health Unit

Department of Transportation – Random Drug & Alcohol Testing

Drug and Alcohal Test Vial 500

Employees operating vehicles in safety-sensitive positions must comply with the DOT Drug and Alcohol Testing Program. Employers are required to have strong programs to prevent drug and alcohol use in the workplace by vehicle operators. Safety-sensitive positions may not only be driving positions, but this program specifically refers to those employees whose duties include driving vehicles. Areas of particular concern are those employees who drive passenger vehicles, drivers of large commercial vehicles, and vehicles that carry hazardous materials. Drivers are responsible for the safe operation of their vehicles at all times must exercise proper care to prevent a life-threatening incident. Driving under the influence of drugs or alcohol can impair judgment, cause drowsiness, or induce other effects that can result in accidents and losses.

Because the results of driving under the influence can be so devastating, a very rigorous regulatory program is in place. The US Department of Transportation regulates workplace drug and alcohol testing programs through its regulation 49 CFR Part 40. This is a very large regulation that covers both employers and service providers. Service providers are those persons or organizations that conduct tests and interpret results.

An employer can require routine drug testing. Typically employers will test newly hired employees as part of the on-boarding process, or can require testing after an accident, or if there is reasonable suspicion of substance abuse that is affecting job performance. Random testing means that any employee who is required to comply with this regulation has an equal probability of being selected at any time to submit to a drug test without cause. The possibility of being randomly selected for a drug test can act as a deterrent for drug use.

To get more information on the applicability of this program for a specific County operation please contact the corresponding departmental Safety Coordinator.

For further information on specific regulatory guidelines please refer to the link(s) below:

CDL Program

EPN Program

DOT Drug and Alcohol Policy and Compliance

DOT Workplace Drug and Alcohol Testing Programs (49 CFR Part 40)

Alcohol and Drugs (CA DMV)