(a) Except as provided in subpart F of this part, no driver shall perform safety-sensitive functions, including driving a commercial motor vehicle, if the driver has engaged in conduct prohibited by subpart B of this part or an alcohol or controlled substances rule of another DOT agency.

(b) No employer shall permit any driver to perform safety-sensitive functions; including driving a commercial motor vehicle, if the employer has determined that the driver has violated this section.

(c) For purposes of this subpart, commercial motor vehicle means a commercial motor vehicle in commerce as defined in § 382.107, and a commercial motor vehicle in interstate commerce as defined in part 390 of this subchapter.

(a) No driver who has engaged in conduct prohibited by subpart B of this part shall perform safety-sensitive functions, including driving a commercial motor vehicle, unless the driver has met the requirements of part 40, subpart O, of this title. No employer shall permit a driver who has engaged in conduct prohibited by subpart B of this part to perform safety-sensitive functions, including driving a commercial motor vehicle, unless the driver has met the requirements of part 40, subpart O, of this title.

(b) No driver whose commercial driving privilege has been removed from the driver's license, pursuant to § 382.501(a), shall drive a commercial motor vehicle until the State Driver Licensing Agency reinstates the CLP or CDL privilege to the driver's license.

(a) No driver tested under the provisions of subpart C of this part who is found to have an alcohol concentration of 0.02 or greater but less than 0.04 shall perform or continue to perform safety-sensitive functions for an employer, including driving a commercial motor vehicle, nor shall an employer permit the driver to perform or continue to perform safety-sensitive functions, until the start of the driver's next regularly scheduled duty period, but not less than 24 hours following administration of the test.

(b) Except as provided in paragraph (a) of this section, no employer shall take any action under this part against a driver based solely on test results showing an alcohol concentration less than 0.04. This does not prohibit an employer with authority independent of this part from taking any action otherwise consistent with law.

Any employer or driver who violates the requirements of this part shall be subject to the civil and/or criminal penalty provisions of 49 U.S.C. 521(b). In addition, any employer or driver who violates the requirements of 49 CFR part 40 shall be subject to the civil and/or criminal penalty provisions of 49 U.S.C. 521(b).