Federal law requires that before anyone drives a vehicle with air brakes that they have passed the Air Brakes knowledge test and has the appropriate CDL license. Air Brakes are fully covered in Section 5 of the CDL manual.
Air brakes use compressed air to make the brakes work. Air brakes are a good and safe way of stopping large and heavy vehicles, but the brakes must be well maintained and used properly. If you want to drive a truck or bus with air brakes, or pull a trailer with air brakes, you must be familiar with air brakes.
The included online practice test covers all information needed to successfully pass the Air Brakes knowledge test.