Requirements for performance.
1.Every motor vehicle and combination of vehicles, at all times and under all conditions of loading, upon application of the service brake, shall be capable of:
(a)Developing a braking force that is not less than the percentage of its gross weight tabulated in subsection 2 for its classification;
(b)Decelerating to a stop from not more than 20 miles per hour at not less than the feet per second per second tabulated in subsection 2 for its classification; and
(c)Stopping from a speed of 20 miles per hour, in not more than the distance tabulated in subsection 2 for its classification, such distance to be measured from the point at which movement of the service brake pedal or control begins.
2.The required braking forces, decelerations and braking distances are tabulated as follows:
3.Tests for deceleration and stopping distance shall be made on a substantially level (not to exceed plus or minus 1-percent grade), dry, smooth, hard surface that is free from loose material.
Section 484D.255 — Requirements for performance.,