If an applicant does not take or fails the air brake component of the knowledge test, or performs the skills test in a vehicle not equipped with air brakes, the State must indicate on the Commercial Learners Permit (CLP) or CDL, if issued, that the person is restricted from operating a CMV equipped with any type of air brakes. For the purposes of the skills test and the restriction, air brakes include any braking system operating fully or partially on the air brake principle.