No person will operate a District school bus unless the person possesses a valid school bus permit and has complied with the regulations of the Department of Revenue. As required by regulations of the Missouri Department of Elementary and Secondary Education, all school bus drivers employed by the District or through a transportation contractor are required to submit a health certificate completed by a physician for each current school term. In addition to the required health certificate, the Board may require evidence of continued good health from individual drivers at any time it deems necessary.