In the parking brake pedal test, what is the required performance standard?

In the parking brake pedal test, the required performance standard is that it must hold the vehicle on a 20% grade. This standard ensures that the parking brake is effective enough to prevent the vehicle from rolling down a steep incline when engaged. A parking brake's primary function is to secure the vehicle in a stationary position, particularly on sloped surfaces, which is critical for safety. By requiring the brake to hold on a 20% grade, the standard assesses that the braking system is robust and reliable, providing a necessary level of assurance to drivers and passengers.

Other standards may not be sufficient to ensure safety on steeper inclines; for example, a lower requirement like 10% or 15% might not adequately reflect the performance needed in real-world scenarios where slopes can be steeper than those grades. It is essential for vehicle safety regulations to take into consideration a range of inclines that a driver might encounter, thus justifying the 20% requirement.