Upper Control Limit (UCL)

Upper control limit - The highest acceptable value or characteristic in a set of items deemed to be of acceptable Quality_. Together with the lower control limit, it specifies the boundaries of acceptable variability in an item to meet Quality_ specifications.

[Category=Data Quality ]

Source: Larry English, http://www.iaidq.com/main/glossary.shtml , 13-Feb-2009 11:30

---

These advertisers support this free service

---

Upper control limit (UCL) - Control limit for points above the central line in a control chart.

[Category=Quality ]

Source: American Society for Quality, 28 October 2010 09:29:47, http://www.asq.org/glossary/

---

UCL - Upper Control Limit (note, different from USL): representing a 3 x sigma upwards deviation from the mean value of a variable (see also LCL). For normally distributed output, 99.7% should fall between UCL and LCL.

When used on control charts, the "3sigma" level can be calculated from sample-to-sample values or batch-to-batch averages using a "magic number", and is used to flag-up unexpected deviations.

[Category=Data Quality ]

Source: iSixSigma, 02 March 2011 08:00:10, https:web.archive.org/web/20111109014246/http:www.isixsigma.com/index.php?option=com_glossary

---

Upper control limit - On the control chart (developed by W. A. Shewhart) an upper control-limit is drawn three standard deviations above the center line.

[Category=Quality ]

Source: The Quality Portal, 29 April 2011 10:09:08, http://thequalityportal.com/glossary/s.htm