What are the primary types of air brakes?

The primary types of air brakes include service brakes, parking brakes, and emergency brakes, which is why this choice is the correct one.

Service brakes are the standard brakes used during regular driving to slow down or stop the vehicle. They engage when pressure is applied to the brake pedal and are essential for controlling the vehicle in normal operating conditions.

Parking brakes, on the other hand, are designed to keep the vehicle stationary when it is not in motion. They provide security when a vehicle is parked, preventing it from rolling away. These brakes are typically applied manually and are essential for safety, particularly on inclines or uneven surfaces.

Emergency brakes serve as a backup to the service brakes and are utilized in situations where the service brakes fail or malfunction. They enable the driver to bring the vehicle to a stop safely if there is a loss of air pressure or other brake failures.

Understanding these three categories is crucial for the operation of vehicles equipped with air brakes, as each serves a different function to enhance safety and control.