First Metre - only connect... the people with the purpose
contact | site map | legal
|
SPC Summary
STATISTICAL PROCESS CONTROL


Statistical Process Control (SPC) charts offer users the chance to monitor the very heartbeat of their processes. By collecting data they can predict performance. Taking sample readings from a process seems straightforward. Or does it? Look more closely. Do we understand our process fully?
 
In manufacturing areas we probably do. In non-manufacturing areas we may be less confident. And who collects the data? What sample size is required? How often are samples taken? These are vital questions to those intending to daily use the control chart  with a view to improving process performance, particularly in non-manufacturing, or service, areas where the techniques are new.
 
The control chart has been with us since 1924.  It has been tried and proven, and accepted as a highly effective tool in improving processes.  In view of the fact that there is currently renewed interest in Shewhart's work, it is important to consider how the control limits were originally set up.
 
However, at the end of the day, it is the logic and rules of collecting data and interpreting the pattern of points on the chart that is the important issue in understanding process behaviour and the discovery of insights for process improvement.

Download pdf booklet on SPC