1.1 This practice covers the mathematical processing of longitudinal profile measurements made by equipment that operates at traffic speeds to produce an estimate of subjective ride quality, termed Ride Number (RN).

1.2 The intent of this practice is to provide the highway community a standard practice for the computing and reporting of an estimate of subjective ride quality for highway pavements from longitudinal profile measurements.

1.3 This practice is based on an algorithm developed in National Cooperative Highway Research Project (NCHRP) 1-23 (1,2), two Ohio Department of Transportation ride quality research projects (3 and 4), as well as additional work presented in Refs (5) and (6).

1.4 the computed estimate of subjective ride quality produced by this practice was named RN in NCHRP Research Project 1-23 (1 and 2) to differentiate it from other measures of ride quality computed from longitudinal profile. Equation 1 in 9.2 represents the mathematical definition of RN.

1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.