ASTM International Standard Practice for Process Capability and Performance Measurement ASTM E2281-15

This practice provides guidance for determining process capability and performance under several common scenarios of use including: normal distribution-based capability and performance indices such as Cp, Cpk, Pp, and Ppk; process capability using attribute data for non-conforming units and non-conformities per unit type variables; and additional methods in working with process capability or performance. Process capability is linked to the use of control charts and the state of statistical control. A process must be studied to evaluate its state of control before evaluating process capability. The behavior of a process in the state of statistical control is used to describe its capability.