Final answer:
The braking power of the spring brakes relies on the proper adjustment of the service brakes. Drivers and maintenance personnel can perform basic tests on spring brakes, but complete servicing requires professional brake technicians.
Step-by-step explanation:
The braking power of the spring brakes depends on the service brakes being in adjustment. If service brakes are not properly adjusted, it could negatively impact the effectiveness and safety of the spring brakes. The condition of the service brakes is crucial because the spring brakes in commercial vehicles, which are essentially a part of the parking/emergency brake system, rely on the baseline adjustments and conditions of the service brakes to function properly. When the service brakes are out of adjustment, the spring brakes may not provide adequate holding force.
Furthermore, understanding brake system maintenance and testing is essential for safety. While it's true that specialized knowledge is required to fully service and inspect brake systems, a basic functional test of the spring brakes can often be performed by drivers or fleet maintenance personnel to identify obvious deficiencies before the vehicle is operated.
It is not true that only highly trained brake service personnel can test the spring brakes; however, for a comprehensive inspection and any necessary adjustments, professional brake technicians with the proper training and tools are required.