What is the rejection criterion regarding brake disc thickness?

The rejection criterion regarding brake disc thickness is that the thickness must be thinner than the discard thickness stamped on the disc. This criterion is critical for ensuring the brakes operate effectively. Discs that fall below this designated discard thickness can compromise braking performance because they may not provide enough surface area for the brake pads to generate the necessary friction. Thin brake discs can lead to overheating, reduced braking ability, and potentially unsafe driving conditions. By following this criterion, inspectors can help ensure that vehicles are equipped with adequate braking systems, which is essential for safety on the road.