Control Limit Application
Are control limits established from an individual process / machine / equipment / tooling / station data or more than 1 machine / equipment / tooling / station data (wherever applicable), after collecting adequate sub-groups over time?
Are the trial control limits established after eliminating all assignable causes & non-random pattern?
Are the control limits revised whenever applicable (e.g. after a major process improvement, change in sample size, etc.)?
Are the out-of-control & zone rules appropriately selected and applied to increase sensitivity considering the situation at hand?