What are the first steps in adjusting the brakes on an air brake system?

Answer: B — Loosen the adjusting bolt and turn the adjustment screw

In the process of adjusting the brakes on an air brake system, the initial step involves loosening the adjusting bolt and turning the adjustment screw. This is critical because it allows you to effectively change the brake's setting to ensure they are neither too tight nor too loose. Proper adjustment is essential for maintaining optimal brake performance and safety. When the adjusting screw is turned, it modifies the distance between the brake shoes and the brake drum, which directly impacts braking efficiency. If the brakes are too loose, stopping power will be inadequate, leading to extended stopping distances, whereas if they are too tight, it can cause unnecessary wear and drag, ultimately overheating the brakes. Checking for responsiveness, replacing brake fluid, or test driving to assess brake function are subsequent steps or considerations but do not directly address the initial adjustment process of the brakes. Proper adjustments must be completed before taking further actions like testing or checks.