Glossary
Presentation of some control cards

Control board (ISO3534-2)

Graph on which the values of a statistical measurement made on a series of samples are plotted in a particular order to orient the process according to this measurement and to control and reduce variation.

Center line

Line on a control chart representing the expected object or the historical average of the statistic plotted.

Control limit (ISO3534-2)

Value used to determine the stability of a process.

Monitoring limits (ISO3534-2)

Control limits between which the statistical value under consideration lies with a high probability when the process is in a state of statistical control.