Physical qualification is the condition most likely to lapse, and § 391.41(a)(1)(i) states it plainly: a person subject to this part must not operate a commercial motor vehicle unless medically certified as physically qualified to do so, and — except as the commercial license exception provides — must have on their person when on duty the original or a copy of a current medical examiner’s certificate. A driver who qualifies by virtue of a medical variance from FMCSA, in the form of an exemption letter or a skill performance evaluation certificate, must carry a copy of that variance documentation when on duty under § 391.41(a)(1)(ii) — the paperwork counterpart of the V restriction code § 4.5 covered.

The carrying requirement has been softened for license holders. Under § 391.41(a)(2), on or after June 23, 2025, a driver required to have a commercial driver’s license or commercial learner’s permit who has a current medical examiner’s certificate documenting that they meet the physical qualification requirements no longer needs to carry that certificate on their person. The certificate still has to exist and still has to be current; what changed is whether it must be in your pocket.

Who may examine you is fixed. § 391.43(a) requires the medical examination be performed by a medical examiner listed on the National Registry of Certified Medical Examiners, with one exception at § 391.43(b): a licensed ophthalmologist or licensed optometrist may perform the part of the examination involving visual acuity, field of vision and the ability to recognize colors as specified in § 391.41(b)(10). § 391.45 then sets who must be examined and certified — including any person not previously certified, and any driver who has not been examined and certified during the preceding 24 months, unless one of the section’s other paragraphs requires it sooner. Twenty-four months is the outer limit, not the schedule: a certificate can be issued for a shorter period, and the date on the certificate is the one that governs.