SPC Control Chart Review

Inspection template for reviewing statistical process control charts for trends, rule violations, out-of-control signals, and corrective actions.

Review Scope and Chart Identification

• Chart type and process identified
  Verify the SPC chart type, process name, product or line, and review period are clearly identified.
• Review period matches required frequency
  Confirm the chart review covers the required time window per SOP or control plan.
• Inspector verified latest revision of control plan or SOP
  Confirm the chart is being reviewed against the current approved control plan, work instruction, or SOP.
• Data source and sample size documented
  Verify the chart includes the data source, subgroup size, and sample count used to generate the control chart.
• Chart baseline or control limit setup is approved
  Confirm the baseline period and control limits were established using an approved method and are documented.

Control Limits and Data Integrity

• Upper and lower control limits are displayed
  Verify UCL and LCL are visible on the chart where applicable.
• Center line is displayed and correct
  Confirm the center line or process average is shown and matches the approved calculation.
• Plotted data matches source records
  Verify plotted values match the source data or system record without transcription errors.
• Missing data points or gaps explained
  Confirm any missing points, skipped subgroups, or chart gaps are documented with a valid reason.
• Measurement system or data collection issues noted
  Check whether any gauge, sampling, or data-entry issues could affect chart validity and are documented as non-conformances if needed.

Trend and Rule Violation Review

• No points beyond control limits
  Confirm there are no out-of-control points outside the UCL or LCL.
• No sustained run or shift pattern detected
  Check for runs, shifts, or sequences indicating special-cause variation per the applicable SPC rule set.
• No trend pattern detected
  Verify there is no sustained upward or downward trend that suggests process drift.
• No rule violations under the applicable SPC rule set
  Confirm the chart does not violate the organization's defined SPC rules, such as Western Electric or Nelson rules, if used by procedure.
• Process variation remains within expected common-cause behavior
  Assess whether the chart indicates stable common-cause variation or whether special-cause investigation is required.

Out-of-Control Signals and Investigation

• Out-of-control signals identified and logged
  Record any points, patterns, or signals that triggered an out-of-control condition.
• Immediate containment action taken
  Confirm affected product, lot, or process output was contained or segregated when a signal was found.
• Root cause investigation initiated
  Verify a documented investigation was started for any special-cause event or repeated rule violation.
• Investigation owner assigned
  Confirm a responsible owner, department, or competent person is assigned to the investigation.
• Disposition of affected product documented
  Verify disposition decisions such as rework, scrap, hold, or release are documented for affected material.

Corrective Actions and Effectiveness

• Corrective action documented for each non-conformance
  Confirm each chart deficiency or special-cause event has a documented corrective action.
• Due date assigned for corrective actions
  Verify each corrective action has a target completion date.
• Effectiveness check completed or scheduled
  Confirm a follow-up review is completed or scheduled to verify the corrective action reduced recurrence.
• Preventive action or process update required
  Determine whether the control plan, sampling plan, training, or SOP needs updating to prevent recurrence.
• Corrective action status
  Record the current status of the action items associated with this review.

Review Sign-Off

• Overall chart review disposition
  Select whether the chart review passed, passed with observations, or failed.
• Inspector comments
  Summarize key observations, rule violations, and follow-up needs.
• Inspector signature
  Inspector or quality engineer sign-off confirming the review is complete.