1. Rule 1: One point outside the control limits If a point falls outside the upper or lower control limits, something unusual has happened. 2. Rule 2: Eight or more points in a row on one side of the centerline If eight or more points are all above or all below the centerline, the process may have shifted. 3. Rule 3: Six or more points in a row showing a steady increase or decrease If six or more points trend up or down, it suggests a consistent change in the process. 4. Rule 4: Two out of three points near the control limits If two of three points are near the control limits, the process is approaching its limits. 5. Rule 5: Fifteen or more points clustered near the centerline If 15 or more points are close to the centerline, the process might be too stable or not varying enough.