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As an employee performing safety-sensitive functions in the transportation industry, you are responsible for providing a safe work environment for your co-workers and the traveling public. Creating a safe work environment not only means following established work rules but also following the DOT's rules on drug use and alcohol misuse.

The following questions and answers will help you better understand the DOT's drug and alcohol testing regulations, as well as, provide resources in the event you or your co-worker need help with a drug or alcohol abuse problem.

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Why am I being tested?

After several significant transportation accidents, Congress passed the Omnibus Transportation Employee Testing Act of 1991, because they recognized the safety need for ensuring drug- and alcohol-free transportation employees. The "Act" required DOT Agencies to implement drug testing of safety-sensitive transportation employees in the aviation, trucking (including school bus drivers, and certain limousine and van drivers), railroads, and mass transit industries. In 1994, DOT added alcohol testing requirements to its regulations.

What are the drug & alcohol testing rules and where do I find them?

The DOT agencies (the Federal Aviation Administration [aviation], the Federal Motor Carrier Safety Administration [trucking], the Federal Railroad Administration [rail], the Federal Transit Administration [mass transit] and the Pipeline and Hazardous Materials Safety Administration [pipeline]) and the United States Coast Guard (USCG) [maritime] each have industry specific regulations which in total cover approximately 6.5 million transportation employees who perform safety-sensitive functions. These regulations spell out who is subject to testing, when and in what circumstances. These regulations can be found on our web site.

If you are an employer in the aviation, trucking, railroad, mass transit, pipeline or maritime industries, or if you have employees who perform DOT identified safety-sensitive positions, you must implement whichever regulation(s) apply.

If you are an employee in the aviation, trucking, railroad, mass transit, pipeline or maritime industries, or if you work in a DOT identified safety-sensitive position, you must comply with whichever regulation(s) apply.

The DOT also has procedures which apply to all transportation employee Federal testing which can be found in another regulation, referred to here as "Part 40." Each of the DOT agencies and the USCG follow Part 40 by including its procedures in their regulations. Part 40 states: what specimens are collected; who performs the drug and alcohol tests; how to conduct those tests; what procedures to use when testing, and the mandatory return to duty requirements of an employee returning to safety-sensitive service following a DOT drug and/or alcohol rule violation.

When can I be tested?

Pre-employment testing

  • Occurs prior to hire or transfer into a safety-sensitive function.
  • The employer may require pre-employment alcohol testing in addition to pre-employment drug testing.  The alcohol test would need to be conducted prior to performing safety-sensitive duties.
    • FRA Only - A pre-employment drug test is a one-time requirement for the employee per employer. 

Random testing

  • Unannounced on an ongoing basis, spread reasonably throughout the calendar year, using a scientifically valid method in which each covered employee has an equal chance of being selected for testing.

    • FMCSA Only - Owner-operators, not leased to a motor carrier, are required to belong to a consortium to satisfy the random testing requirement.

    • PHMSA and USCG - Random alcohol testing is not authorized

    • FRA Only - Random testing is not authorized for partial compliance railroads (those which 15 or less covered service employees) or contractors working exclusively for partial compliance railroads.

Post-accident testing

  • Occurs following the Modes qualifying accident.
    • FRA - 219.201
    • FMCSA - 49 CFR Part 382.303
    • FAA - 14 CFR Part 120.109(c) & 120.217(b)
    • FTA - 655.44
    • PHMSA - 199.105(b)
    • USCG - 16.240 & 4.03-1

Reasonable Cause - FRA only

  • May occur following an accident/incident that does not qualify for Part 219 Subpart C Post-accident testing described in Part 219.201.
  • A railroad or a contractor to a railroad must identify if they will conduct FRA Reasonable Cause testing, or not, when they submit their FRA Part 219 random testing plan to FRA for approval/acceptance and must treat all regulated employees the same, once selected.
    • If a railroad or their regulated contractor select to conduct Federal FRA Reasonable Cause testing, then they cannot perform company (non-DOT) testing for any event described in Part 219.403(a) or (b).
    • If a railroad selects to conduct company (non-DOT) Reasonable Cause testing, then the railroad or their regulated contractor cannot perform FRA Reasonable Cause testing for any event described in Part 219.403 (a) or (b)
  • Partial compliance railroads are not authorized to conduct FRA Reasonable Cause testing.

Reasonable Cause/Suspicion testing

  • Occurs when a company official or supervisor - based on their training - believes the employee shows signs of drug use and/or alcohol misuse.

Return-to-duty and Follow-up testing

  • Occurs after an employee has a verified positive drug test, positive alcohol test result or refusal to test. The employee must take a return-to-duty test prior to returning to safety-sensitive functions.
  • The employee will be subject to a minimum of 6 unannounced follow-up tests in the first 12 months. Depending on the Substance Abuse Professional's recommendations, follow-up testing may occur for up to 60 months
  • The follow-up testing plan “follows the employee” to subsequent employers or through breaks in service.
  • FRA Only - Locomotive engineers and conductors will be subject to at least 6 unannounced drug and alcohol tests during the first 12 months.

Periodic Testing - USCG Only

  • Occurs during the original issuance or renewal or upgrade of a Coast Guard issued license or merchant mariner’s documents.

In addition to DOT testing, your company may have its own testing program.

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What specimens are collected for testing?

Testing for drugs:

  • A urine specimen is collected and sent to a certified laboratory for analysis
    • Devices that provide instant results are not authorized for DOT testing.
    • Only urine specimens are authorized for DOT drug testing.

Testing for alcohol:

  • Alcohol testing involves analyzing your breath or saliva for initial (screening) tests and breath for confirmation tests. The specimen is collected and analyzed by an approved alcohol testing device.

FRA Only:

  • In addition to urine and breath (as applicable), FRA Part 219 Subpart C qualifying Post-Accident testing will require drawing your blood, which will be tested for alcohol and drugs (as necessary).

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For what drugs will I be tested?

You will be tested for the following drugs:

  • Marijuana
  • Cocaine
  • Opioids (Codeine, morphine, heroin, hydrocodone, hydromorphone, oxycodone, oxymorphone)
  • Phencyclidine (PCP)
  • Amphetamines, Methamphetamines, and Methylenedioxymethamphetamine (MDMA)

FRA Only - For FRA Part 219 Subpart C qualifying Post-Accident Testing you will be tested for more than the five drug categories listed above

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Can I use over the counter meds and perform covered functions?

Prescription medicine and OTC drugs are allowed; however, you must meet minimum standards:

  • The medicine is prescribed to you by a licensed physician, such as your personal doctor.
  • The treating/prescribing physician has made a good faith judgment that the use of the substance at the prescribed or authorized dosage level is consistent with the safe performance of your duties.
    • Best Practice: To assist your doctor in prescribing the best possible treatment, consider providing your physician with a detailed description of your job. A title alone may not be sufficient. Many employers give employees a written, detailed description of their job functions to provide their doctors at the time of the exam.

The substance is used at the dosage prescribed or authorized.

If you are being treated by more than one physician, you must show that at least one of the treating physicians has been informed of all prescribed and authorized medication and has determined that the use of the medications is consistent with the safe performance of your duties.

Taking the prescription medication and performing your DOT safety-sensitive functions is not prohibited by agency regulations.

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What is a refusal to test?

  • Refusals include, but are not limited to:
    • No-show (failure to appear at the test collection site at the designated time)
    • Failure to remain at the testing site until the collection is completed
    • Adulteration (urine specimen containing a substance or a concentration of a substance inconsistent with human urine)
    • Substitution (urine specimen containing creatinine and specific gravity levels inconsistent with human urine)
    • Failure to cooperate with any part of the testing process

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Should I refuse a test if I believe I was unfairly selected for testing?

A good rule of thumb is "comply, then complain." If you are instructed to submit to a DOT drug and/or alcohol test and you don't agree with the reason or rationale for the test, you should take the test.

Don't interfere with the testing process or refuse the test. Instead, after the test express your concerns about the testing event to your employer (for example, a detailed letter to your company or by an agreed upon grievance procedure if you are a member of labor organization). You can also express your concern to the Drug and Alcohol Program Manager (DAPM) for the DOT agency that regulates you and your employer.

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What will happen to me if the laboratory identifies my specimen as positive for one or more drugs, or as adulterated or substituted?

You will have the opportunity to speak directly with a Medical Review Officer (MRO). During your interview you will have an opportunity to provide information and/or medical documentation to explain/support why your specimen was positive, adulterated or substituted. Based on the information you provide, the MRO will "verify" your result by determining whether or not there is a legitimate medical reason for your test result. The MRO will report your result to your employer only after making this determination.

During the interview the MRO will ask if you would like to verify the laboratory's result by having your split or "B" specimen (your primary specimen is the "A" sample) sent to another laboratory for analysis. You will have 72 hours from the time the MRO verifies your result to request an analysis of your "B" specimen. Who pays for the analysis is between you and your employer, but the MRO cannot reject or hold up your request because of payment issues.

What will happen to me if I violate a DOT drug & alcohol rule (e.g. test positive, or refuse a test)?

Your employer is required to immediately remove you from performing safety-sensitive functions. You will not be permitted to return to DOT regulated safety-sensitive functions until you have:

  • Undergone an evaluation by a Substance Abuse Professional (SAP). Your employer must provide you with a list of SAPs that you can use;
  • Successfully completed any course, counseling or treatment prescribed by the SAP prior to returning to service;
  • Undergone a follow up evaluation by the same SAP to determine your compliance with their recommendations; AND
  • Provided a breath and/or urine specimen that tests negative for drugs and/or alcohol prior to returning to DOT regulated safety-sensitive functions.

You will also be subject to unannounced "Follow-Up" testing for drugs and/or alcohol for at least 6 times during the first 12 months of active service with the possibility of unannounced testing for up to 60 months (as prescribed by the SAP).  The Return-to-Duty and Follow-Up drug tests will be conducted under direct observation.

  • FAA Only
    • If you hold a certificate issued by the FAA, it may be revoked.
    • If you test positive on two required tests, you may be permanently disqualified from performing the same type of safety-sensitive duties.
  • FRA Only
    • A refusal to test prohibits you from performing regulated service at any railroad for a minimum of 9 months.
  • USCG Only
    • Credentialed crewmembers who have a verified positive drug test result or verified refusal to take a drug test will be subject to further action by the Coast Guard.
  • Your company policy and/or collective bargaining agreement will determine whether you will be permitted an opportunity for rehabilitation or may be terminated from employment.

What is considered misuse of alcohol?

Misuse of alcohol is:

  • Reporting for or remaining on duty with an alcohol concentration of 0.04 or greater.
  • Using or possessing alcohol while performing safety-sensitive functions,
  • Using alcohol within 4 hours of reporting for or receiving notice to report for duty (whichever is the lesser time period) performing safety-sensitive functions.

FAA only

  • Using alcohol within 8 hrs for a flight crewmember (pilot or flight attendant or air traffic controller)
  • Using alcohol following an accident (14 CFR Part 120.19 and 120.37)

Alcohol misuse is a violation of the regulations and has consequences.

FRA Only - A positive alcohol test of .040 BAC or greater will affect your locomotive engineer (§ 240.119) or conductor (§ 242.115) certification.

How do I find a Substance Abuse Professional (SAP) who is qualified to act in the U.S. Department of Transportation (DOT) drug and alcohol testing program?

As an employer, you must provide employees with a list of SAPs qualified under §40.281.  The regulation [§40.287] requires the employer to provide the employee with a list of qualified SAPs. Your failure to provide such a list could result in sanctions issued by the DOT Modal Administration with jurisdiction over you.

As an employee, ask your employer for a list of SAPs in your area (even if the employer fired you or did not hire you).  A SAP qualified to act in the DOT drug and alcohol testing program must meet the SAP qualification requirements in §40.281.

If your employer did not provide you with a list of qualified SAPs, search the internet using search terms such as “DOT qualified SAP” or “DOT and SAP”.

Please know that neither the DOT nor any of its Agencies has or maintains a list of SAPs or any other service agents.

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Will I lose my job if I violate a DOT Agency drug and alcohol rule?

All employment decisions belong solely to the employer. DOT regulations do not address employment actions such as hiring, firing or leaves of absence. DOT and USCG regulation may prohibit you from performing your safety-sensitive functions after a positive test result or refusal to submit to testing. You should be aware that a positive, adulterated or substituted DOT drug or alcohol test may trigger consequences based on company policy or employment agreement.

Are my results confidential?

Your test results are confidential. An employer or service agent (e.g., a testing laboratory, Medical Review Officer or Substance Abuse Professional) is not permitted to disclose your test result(s) without your written consent. In certain situations, however, your test information may be released without your consent; such as, legal proceedings, grievances, or administrative proceedings brought on by you or on your behalf, which resulted from a positive, adulterated, substituted test result or refusal. When your employer releases your drug and alcohol testing records, the employer must notify you in writing.

Will my results follow me to other employers?

Yes, your drug and alcohol testing history will follow you to your new employer. Employers are required by law to provide certain records of your DOT drug and alcohol testing history to your new employer, only when you sign a specific written release regarding that information.

This is to ensure that, when necessary, you complete the return-to-duty process and your follow up testing program.

In addition, as of January 6, 2020, FMCSA requires employers and service agents to report drug and alcohol violations to the Drug and Alcohol Clearinghouse.  It also requires FMCSA-regulated employers to query the Clearinghouse about prospective employees to verify there are no violations before performing safety-sensitive functions, as well as, querying the Clearinghouse on current employees at least once a year.

What should I do if I believe I or my co-worker has an alcohol or substance abuse problem?

Most every community in the country has resources available to confidentially assist you through the evaluation and treatment of your problem. If you would like to find a treatment facility close to you, check with your local yellow pages, local health department or visit the U.S. Department of Health and Human Services treatment facility locator. This site provides contact information for substance abuse treatment programs by state, city and U.S. Territory.

Also, many work-place programs are in place to assist employees and family members with substance abuse, mental health and other problems that affect their job performance. While these may vary by industry, here is an overview of programs that may be available to you:

Employee Assistance Programs (EAPs)
While not required by DOT agency regulations, EAPs may be available to you as a matter of company policy. EAPs are generally provided by employers or unions. EAP programs vary considerably in design and scope. Some focus only on substance abuse problems, while others take a broad brush approach and include your health and family problems. Some programs include prevention, and health and wellness activities. Some are linked to your health benefits. With limited exceptions, these programs offer full privacy and confidentiality.

Voluntary Referral Programs
Often sponsored by employers or unions (or the FRA under 49 CFR Part 219 Subpart K), referral programs provide an opportunity to self-report to your employer a substance abuse problem before you violate DOT and/or company rules. This gives you an opportunity for evaluation and treatment and may allow you to keep your job. Check with your employer to see if it offers a voluntary referral program.

FMCSA only:  Employees who admit to alcohol misuse or controlled substances use are not subject to the referral, evaluation and treatment requirements of this Parts 382 and 40[see 49 CFR Part 382.121].

Peer Reporting Programs
These programs which are generally sponsored by employers or unions, encourage you to identify co-workers with substance abuse problems because the safety of everyone depends on it. Using peers to convince troubled friends and co-workers who have a problem to seek help often guarantees the co-worker struggling with substance abuse issues the same benefits as if he had self-reported.


Helpful Links

NOTE:  This page contains links to non-Federal websites.  The U.S. government, its organizational units, and its employees are not responsible for the information found through these links.  No endorsement of these sites or their content is provided or implied.

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