49 CFR § 392.5 - Alcohol prohibition.
(a) No driver shall—
(1) Use alcohol, as defined in § 382.107 of this subchapter, or be under the influence of alcohol, within 4 hours before going on duty or operating, or having physical control of, a commercial motor vehicle; or
(2) Use alcohol, be under the influence of alcohol, or have any measured alcohol concentration or detected presence of alcohol, while on duty, or operating, or in physical control of a commercial motor vehicle; or
(3) Be on duty or operate a commercial motor vehicle while the driver possesses wine of not less than one-half of one per centum of alcohol by volume, beer as defined in 26 U.S.C. 5052(a), of the Internal Revenue Code of 1954, or distilled spirits as defined in section 5002(a)(8), of such Code. However, this does not apply to possession of wine, beer, or distilled spirits which are:
(i) Manifested and transported as part of a shipment; or
(ii) Possessed or used by bus passengers.
(b) No motor carrier shall require or permit a driver to—
(1) Violate any provision of paragraph (a) of this section; or
(2) Be on duty or operate a commercial motor vehicle if, by the driver's general appearance or conduct or by other substantiating evidence, the driver appears to have used alcohol within the preceding four hours.
(c) Any driver who is found to be in violation of the provisons of paragraph (a) or (b) of this section shall be placed out-of-service immediately for a period of 24 hours.
(1) The 24-hour out-of-service period will commence upon issuance of an out-of-service order.
(2) No driver shall violate the terms of an out-of-service order issued under this section.
(d) Any driver who is issued an out-of-service order under this section shall:
(1) Report such issuance to his/her employer within 24 hours; and
(2) Report such issuance to a State official, designated by the State which issued his/her driver's license, within 30 days unless the driver chooses to request a review of the order. In this case, the driver shall report the order to the State official within 30 days of an affirmation of the order by either the Division Administrator or State Director for the geographical area or the Administrator.
(e) Any driver who is subject to an out-of-service order under this section may petition for review of that order by submitting a petition for review in writing within 10 days of the issuance of the order to the Division Administrator or State Director for the geographical area in which the order was issued. The Division Administrator or State Director may affirm or reverse the order. Any driver adversely affected by such order of the Regional Director of Motor Carriers may petition the Administrator for review in accordance with 49 CFR 386.13.