49 C.F.R. § 391.45 : Transportation — OTHER REGULATIONS RELATING TO TRANSPORTATION — FEDERAL MOTOR CARRIER SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION — FEDERAL MOTOR CARRIER SAFETY REGULATIONS — QUALIFICATIONS OF DRIVERS AND LONGER COMBINATION VEHICLE (LCV) DRIVER INSTRUCTORS — PHYSICAL QUALIFICATIONS AND EXAMINATIONS — Persons who must be medically examined and certified

The following persons must be medically examined and certified in accordance with §391.43 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) Any driver who has not been medically examined and certified as qualified to operate a commercial motor vehicle during the preceding 24 months, unless the driver is required to be examined and certified in accordance with paragraph (c), (d), (e), (f), (g), or (h) of this section;
(c) Any driver authorized to operate a commercial motor vehicle only within an exempt intra-city zone pursuant to § 391.62, if such driver has not been medically examined and certified as qualified to drive in such zone during the preceding 12 months;
(d) Any driver authorized to operate a commercial motor vehicle only by operation of the exemption in § 391.64, if such driver has not been medically examined and certified as qualified to drive during the preceding 12 months;
(e) Any driver who has diabetes mellitus treated with insulin for control and who has obtained a medical examiner's certificate under the standards in § 391.46, if such driver's most recent medical examination and certification as qualified to drive did not occur during the preceding 12 months;
(f) Any driver who does not satisfy, with the worse eye, either the distant visual acuity standard with corrective lenses or the field of vision standard, or both, in § 391.41(b)(10)(i) and who has obtained a medical examiner's certificate under the standards in § 391.44, if such driver's most recent medical examination and certification as qualified to drive did not occur during the preceding 12 months;
(g) Any driver whose ability to perform his or her normal duties has been impaired by a physical or mental injury or disease; and
(h) On or after June 23, 2025, 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 § 391.43.

49 C.F.R. §391.45

35 FR 6460, 4/22/1970, as amended at 36 FR 223, 1/7/1971; 54 FR 12202, 3/24/1989; 61 FR 13347, 3/26/1996; 80 FR 22821, 4/23/2015; 80 FR 59075, 10/1/2015; 83 FR 28782, 6/21/2018; 83 FR 47520, 11/19/2018; as amended at 86 FR 32651, 6/22/2021; 87 FR 3417, 3/22/2022