Acceptable quality limit
The acceptable quality limit (AQL) is the worst tolerable process average (mean) in percentage or ratio that is still considered acceptable; that is, it is at an acceptable quality level.[1] Closely related terms are the rejectable quality limit and rejectable quality level (RQL).[1][2] In a quality control procedure, a process is said to be at an acceptable quality level if the appropriate statistic used to construct a control chart does not fall outside the bounds of the acceptable quality limits. Otherwise, the process is said to be at a rejectable control level.
In 2008 the usage of the abbreviation AQL for the term "acceptable quality limit" was changed in the standards issued by at least one national standards organization (ANSI/ASQ) to relate to the term "acceptance quality level".[3][4] It is unclear whether this interpretation will be brought into general usage, but the underlying meaning remains the same.
An acceptable quality level is a test and/or inspection standard that prescribes the range of the number of defective components that is considered acceptable when
See also
- Acceptability
- Acceptance sampling
- Statistical process control
- Control limits
References
- ^ ISBN 0-19-920613-9
- ISBN 978-0-521-51522-1
- ^ ANSI/ASQ Z1.4-2008 Sampling Procedures and Tables for Inspection by Attributes.
- ^ http://www.aqlinspectorsrule.com/Z1-4-2008.html Archived 2009-06-01 at the Wayback Machine AQL Inspectors Rule
Further reading
- Hughes, Charles C. (2005). State construction quality assurance programs. Washington, D.C: Transportation Research Board. ISBN 0-309-09749-5.
- Pyzdek, Thomas (1989). What every engineer should know about quality control. New York: M. Dekker. ISBN 0-8247-7966-5.