Rp, per ISO 4287, is the max height of any peak to the mean line within one
sampling length.
• Rpm, the mean leveling depth - per rules of ISO 4288, is an averaging of Rp over
5 cutoffs; according to ASME B46.1-2002, Rp calculated over the evaluation
length is Rpm.
• Many instruments, e.g., M2 Series, measure Rpm but report the result as R