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Frequently Asked Questions

he following are some of the questions the Office for Drug and Alcohol Policy and Compliance (ODAPC) has received which did not require an interpretation but rather a general response. As such, the ODAPC staff thought that those subject to Department of Transportation (DOT) testing would benefit from the responses already provided.

These responses do not substitute for the regulations found in 49 CFR Part 40 or any other DOT agency or United States Coast Guard (USCG) specific regulation. If you have a question about the DOT drug and alcohol testing program rules, read the regulatory text.

CLICK HERE for commercial motor vehicle (CMV) driver medical qualification questions


As an employee or employer, how do I know if I am subject to DOT testing?

Generally, DOT regulations cover safety-sensitive transportation employers and employees. Each DOT agency (e.g. FRA, FMCSA, FTA, FAA, and PHMSA) and the USCG have specific drug and alcohol testing regulations that outline who is subject to their testing regulations.

How does 49 CFR Part 40 differ from the DOT Agency specific regulations?

49 CFR Part 40 (commonly referred to as "Part 40") states:

  • how drug and alcohol testing is conducted,
  • who is authorized to participate in the drug and alcohol testing program, and
  • what employees must do before they may return-to-duty following a drug and/or alcohol violation.

The DOT Agency and the USCG specific regulations state:

  • the agency's prohibitions on drug and alcohol use,
  • who is subject to the regulations,
  • what testing is authorized,
  • when testing is authorized, and
  • the consequences of non-compliance.

The DOT Agencies and the USCG incorporate Part 40 into their regulations and enforce compliance of all their respective regulations.

Will I lose my job if I test positive or refuse a test?

The DOT regulations do not address hiring, termination, or other employment actions. These decisions are solely the employer's, which may be based on company policy and/or any collective bargaining agreements.

What happens to me when I test positive or refuse to test (i.e. adulterate, or substitute my urine specimen, or decline to be tested)?

When you test positive or refuse a test, you are not permitted to perform safety-sensitive duties until you have seen a Substance Abuse Professional (SAP) and successfully completed the return-to-duty process, which includes a Federal return-to-duty drug and/or alcohol test. Working in a safety-sensitive position before successfully completing the return-to-duty process is a violation of the regulations.

Who pays for the DOT drug or alcohol test or SAP recommended treatment/education, the employer or employee?

The Department's regulations are silent on who is responsible for paying for the testing or SAP recommended treatment/education. Payment may be based an understanding between the employer and employee, including applicants for safety-sensitive positions.

An employer may not, however, refrain from sending a "split specimen" for testing because the employee does not pay for the test in advance.

Do I need to be DOT certified to participate in DOT’s drug and alcohol testing program as a service agent (i.e. urine specimen collector, breath alcohol technician (BAT), screening test technician (STT), medical review officer (MRO), substance abuse professional (SAP), consortium/third-party administrator (C/TPA), or laboratory)?

The regulations do not authorize the DOT to certify service agents. Nor does the Department offer a certificate to participate in DOT's drug and alcohol testing program.

The regulations only require that you meet the qualification and training outlined in 49 CFR Part 40 and maintain the necessary documents to prove your qualifications.

As a laboratory, you can only participate in DOT's drug testing program if you are certified by the Department of Health and Human Services under the National Laboratory Certification Program.

If I want to become a service agent, where do I find a list of courses or training sessions?

ODAPC does not maintain a listing of courses or training sessions. However, some of these may be found on various Internet web sites supported by national associations and other transportation industry related service agents.

As an employer, where do I find a list of qualified service agents (e.g. urine specimen collectors, BATs, STTs, MROs, SAPs, or laboratories)?

ODAPC does not develop or maintain a list of qualified service agents. You can check with industry associations, the yellow pages, or the web for service agents. The Department of Health and Human Services does, however, publish a list (monthly) of certified laboratories.

As an employer, you are ultimately responsible for compliance with the DOT drug and alcohol testing regulations; therefore, you must ensure that the service agent you use meets all the DOT required qualifications before using the service agent.

Is there a list of prohibited drugs for being medically qualified to drive a commercial motor vehicle (CMV)?

Section 391.41(b)(12) states: A person is physically qualified to drive a CMV if that person does not use a controlled substance identified in 21 CFR 1308.11, Schedule I, an amphetamine, a narcotic, or any other habit-forming drug. Exception: A driver may use such a substance or drug, if the substance or drug is prescribed by a licensed medical practitioner who is familiar with the driver’s medical history and assigned duties; and has advised the driver that the prescribed substance or drug will not adversely affect the driver’s ability to safely operate a CMV. This exception does not apply to methadone.

Medical Examiners are required to give careful consideration to the effects of medications on a driver’s ability to operate a CMV safely before rendering the driver qualified.

For information on specific drugs and CMV driver qualification, please visit the Federal Motor Carrier Safety Administration's Medical Program website at: http://www.fmcsa.dot.gov/medical. Questions about the effects of many drugs and driver qualification are answered in the Frequently Asked Questions (FAQs) section. You may also e-mail your questions to the Physical Qualifications Division at fmcsamedical@dot.gov or call and ask for a Specialist on (202) 366-4001.

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