In order to drive a semi truck equipped with air brakes, a standard Commercial Drivers License (CDL) is required. However, certain endorsements and restrictions apply when driving such trucks. For instance, those driving trucks equipped with air brakes are required to take an air brake knowledge test.
Drivers must also take a road test in a truck equipped with air brakes in order to show proficiency with the vehicle. Those with current CDLs can have the necessary endorsement and restrictions added or removed when necessary by visiting the Department of Motor Vehicles. Failure to do so could result in loss of the license.