37 Tex. Admin. Code § 14.12
A person shall not drive a school bus, school activity bus, or multifunction school activity bus unless he/she is physically qualified to do so. Each school bus driver shall undergo and successfully complete an annual physical examination in accordance with the requirements of Title 49, Code of Federal Regulations, Parts 391.41 and 391.43, which list those physical and mental conditions for which the medical examiner is directed to disqualify an applicant. The results of the examination shall be noted on the Medical Examination Report Form for Commercial Driver Medical Certification as published by the United States Department of Transportation (DOT), Federal Motor Carrier Safety Administration in Title 49, Code of Federal Regulations, Part 391.43 according to the figure in this section. A driver shall not operate a school bus, school activity bus, or multifunction school activity bus unless he/she has in their possession the original, or a photographic copy, of a valid medical examiner's certificate stating that he/she is physically qualified to drive a school bus, school activity bus, or multifunction school activity bus.
37 Tex. Admin. Code § 14.12