The following persons must be medically examined and certified in accordance with Sec. 391.43 of this subpart as physically qualified to operate a commercial motor vehicle:
(a) Any person who has not been medically examined and certified as physically qualified to operate a commercial motor vehicle;
(b)(1) Any driver who has not been medically examined and certified as qualified to operate a commercial motor vehicle during the preceding 24 months; or
(1) Any driver who has not been medically examined and certified as qualified to operate a commercial motor vehicle during the preceding 24 months; or
(2) Any driver authorized to operate a commercial motor vehicle only with an exempt intracity zone pursuant to Sec. 391.62, or only by operation of the exemption in Sec. 391.64, if such driver has not been medically examined and certified as qualified to drive in such zone during the preceding 12 months;
(c) Any driver whose ability to perform his/her normal duties has been impaired by a physical or mental injury or disease; and
(d) Beginning June 22, 2018, any person found by a medical examiner not to be physically qualified to operate a commercial motor vehicle under the provisions of paragraph (g)(3) of Sec. 391.43. [35 FR 6460, Apr. 22, 1970, as amended at 36 FR 223, Jan. 7, 1971; 54 FR 12202, Mar. 24, 1989; 61 FR 13347, Mar. 26, 1996; 80 FR 22821, Apr. 23, 2015; 80 FR 59075, Oct. 1, 2015]