scope:

This part of ISO 7870 establishes a guide to the use and understanding of specialzed control charts in situations where commonly used Shewhart control chart approach to the methods of statistical control of a process may either be not applicable or less efficient in detecting unnatural patterns of variation of the process. The specialized control charts included in this International Standard for variables type of data are: a) Moving average and moving range charts b) z-charts; c) Group control charts; d) High-low control charts; e) Trend control charts; f) Control charts for coefficient of variation; g) Control charts for non-normal data. For attributes type of data, specialized control charts included in this International Standard are a) Standardized p-charts; b) Demerit control charts; c) Control charts for inspection by gauging. This International Standard also provides guidance as to when each of the above control charts should be used, their control limits, advantages and limitations. Each control chart is illustrated with an example.