49 CFR 219.101 - Alcohol and drug use prohibited.
(a) Prohibitions. Except as provided in § 219.103 -
(i) Under the influence of or impaired by alcohol;
(ii) Having .04 or more alcohol concentration in the breath or blood; or
(iii) Under the influence of or impaired by any controlled substance.
(3) No employee may use alcohol for whichever is the lesser of the following periods:
(i) Within four hours of reporting for covered service; or
(ii) After receiving notice to report for covered service.
(4) No employee tested under the provisions of this part whose test result indicates an alcohol concentration of .02 or greater but less than .04 may perform or continue to perform covered service functions for a railroad, nor may a railroad permit the employee to perform or continue to perform covered service, until the start of the employee's next regularly scheduled duty period, but not less than eight hours following administration of the test.
(5) If an employee tested under the provisions of this part has a test result indicating an alcohol concentration below 0.02, the test must be considered negative and is not evidence of alcohol misuse. A railroad may not use a federal test result below 0.02 either as evidence in a company proceeding or as a basis for subsequent testing under company authority. A railroad may take further action to compel cooperation in other breath or body fluid testing only if it has an independent basis for doing so.
(b) Controlled substance. “Controlled substance” is defined by § 219.5. Controlled substances are grouped as follows: marijuana, narcotics (such as heroin and codeine), stimulants (such as cocaine and amphetamines), depressants (such as barbiturates and minor tranquilizers), and hallucinogens (such as the drugs known as PCP and LSD). Controlled substances include illicit drugs (Schedule I), drugs that are required to be distributed only by a medical practitioner's prescription or other authorization (Schedules II through IV, and some drugs on Schedule V), and certain preparations for which distribution is through documented over the counter sales (Schedule V only).
(c) Railroad rules. Nothing in this section restricts a railroad from imposing an absolute prohibition on the presence of alcohol or any drug in the body fluids of persons in its employ, whether in furtherance of the purpose of this part or for other purposes.
(d) Construction. This section may not be construed to prohibit the presence of an unopened container of an alcoholic beverage in a private motor vehicle that is not subject to use in the business of the railroad; nor may it be construed to restrict a railroad from prohibiting such presence under its own rules.