1. Specification Limits, Tolerances
Specification limit: conformance boundary specified for a characteristic.
Statistical tolerance limits: limits of the interval for which it can be stated with a given level of confidence that it contains at least a specified proportion of the population

2. Process Specification Conflicts
Type I conflict: the inherent variability of the process is too great or the specification limits are too narrow (Two sided specification limits and less than 6).
Type II conflict: one-sided specification limits and less than 3 .
Type III conflict: the specification limits are too wide for acceptable quality.

3. Actions in the case of Type I Specification Conflict
Action 1 - Changing the process (reduce the spread of the distribution)
Action 2 – try to avoid setting the specification limits tighter than necessary.
Action 3 – setting up an inspection/sorting operation (an interim procedure, not a permanent solution)
Action 4 – adjusting the center

4. Actions in the Case of Type II Specification Conflict
Action 1- Attempt to center the process at a value far enough from the specification limit to avoid individual items outside of the limit (use xbar chart)
Action 2 – Changing the specification limit
Action 3 – Setting up an inspection/sorting operation to find and remove or repair the units of product that fall outside the specification limit.

5. Actions in the Case of Type III Specification Conflict
Action 1 – Conduct more formal programs of process experimentation to determine what range of values cause non-conformities.
Action 2 – Make specification limits more tight.
Action 3 – Establish specification limits on a temporary basis until final values are determined.

6. The Process Capability Index Cp
Cp = (U-L)/6
If Cp = 1, then the natural spread of the process equals the width of specification limits
If Cp < 1 a type I specification conflict occurs
The most typical Cp = (U-L = 8)