Process Capability Study Inspection Checklist [FREE PDF]

Process capability studies are a core requirement under IATF 16949:2016 clause 8.4.1.5 and ISO 9001:2015 clause 9.1.1, mandating that organizations demonstrate their processes can consistently produce output within specification limits. A thorough capability study verifies that Cp and Cpk indices meet minimum thresholds—typically ≥1.33 for new processes per IATF 16949—before full production release. This checklist guides QA Engineers through data collection, analysis, and documentation requireme

  • Industry: Manufacturing QA
  • Frequency: Per Event
  • Estimated Time: 45-75 minutes
  • Role: QA Engineer
  • Total Items: 35
  • Compliance: ISO 9001:2015 Clause 9.1.1 – Monitoring, Measurement, Analysis and Evaluation, IATF 16949:2016 Clause 8.4.1.5 – Process Capability Requirements, IATF 16949:2016 Clause 8.3.3.1 – Product and Manufacturing Process Design Input, AS9100 Rev D Clause 8.5.1.1 – Production Process Verification, Six Sigma DMAIC Measure Phase – Gauge R&R and Capability Analysis

Study Setup and Planning

Verify that all prerequisites for a valid capability study are established before data collection begins.

  • Has a Control Plan been reviewed and approved prior to initiating the capability study?
  • Is the minimum sample size of 125 consecutive parts (or equivalent per customer requirements) planned?
  • Have all special characteristics (KPC/KCC) been identified and flagged for this study?
  • Is the process operating under normal production conditions (standard tooling, operators, materials)?
  • Has a study plan with defined subgroup size and frequency been documented?

Measurement System Verification

Confirm that the measurement system used is capable and verified before data collection.

  • Has a current Gauge R&R study been completed for the measurement system used in this study?
  • Is the measurement equipment calibrated and within its calibration due date?
  • Is the measurement gauge resolution at least 1/10th of the total specification tolerance?
  • Has the calibration certificate number been recorded for all measurement devices used?
  • Is the measurement environment (temperature, humidity, vibration) documented and within acceptable limits?

Data Collection

Verify proper data collection methodology and recording practices during the study.

  • Were parts measured in the order produced (time-ordered sequence maintained)?
  • Was the actual sample size collected as planned (record count)?
  • Were any out-of-control conditions (special causes) identified during data collection?
  • Are raw data sheets or electronic data files retained and linked to this record?
  • Were all process parameters (speed, feed, temperature, etc.) recorded at the time of data collection?

Normality and Statistical Control Verification

Confirm that data meets statistical assumptions required for valid capability index calculations.

  • Was a normality test (e.g., Anderson-Darling, Shapiro-Wilk) performed on the data set?
  • Did the data pass the normality test (p-value ≥ 0.05 or per agreed statistical threshold)?
  • Is the process in statistical control as confirmed by a control chart (no special causes)?
  • Were Western Electric or Nelson run rules applied to the control chart?
  • Is the histogram shape reviewed and documented alongside the control chart?

Capability Index Calculation and Results

Record and verify all process capability and performance indices against required thresholds.

  • What is the calculated Cp (process capability) index for this characteristic?
  • What is the calculated Cpk (process capability index) for this characteristic?
  • What is the calculated Pp (process performance) index?
  • What is the calculated Ppk (process performance index)?
  • Do all calculated indices meet or exceed the minimum customer-specified requirements?

Documentation and Approval

Ensure all study outputs are properly documented, reviewed, and approved per quality system requirements.

  • Has the capability study report been completed with all required fields (part number, date, indices, specs)?
  • Has a QA Manager or authorized approver reviewed and signed the capability study report?
  • Have findings and actions been entered into the organization's quality records system (ERP/QMS)?
  • If capability does not meet requirements, has a corrective action or containment plan been initiated?
  • Has the study been linked to the relevant PPAP package or customer submission, if applicable?

Continuous Improvement and Follow-Up

Identify improvement opportunities and verify ongoing monitoring plans are established.

  • Has a reaction plan been defined for when the process goes out of control in production?
  • Has a follow-up study date been scheduled if initial capability was marginal (1.33 ≤ Cpk < 1.67)?
  • Have improvement opportunities (sources of variation reduction) been documented and assigned?
  • Is ongoing SPC monitoring planned and included in the updated Control Plan?
  • Has the process owner been notified of capability study results and required actions?

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Why Use This Process Capability Study Inspection Checklist [FREE PDF]?

This process capability study inspection checklist [free pdf] helps manufacturing qa teams maintain compliance and operational excellence. Designed for qa engineer professionals, this checklist covers 35 critical inspection points across 7 sections. Recommended frequency: per event.

Ensures compliance with ISO 9001:2015 Clause 9.1.1 – Monitoring, Measurement, Analysis and Evaluation, IATF 16949:2016 Clause 8.4.1.5 – Process Capability Requirements, IATF 16949:2016 Clause 8.3.3.1 – Product and Manufacturing Process Design Input, AS9100 Rev D Clause 8.5.1.1 – Production Process Verification, Six Sigma DMAIC Measure Phase – Gauge R&R and Capability Analysis. Regulatory-aligned for audit readiness and inspection documentation.

Frequently Asked Questions

What does the Process Capability Study Inspection Checklist [FREE PDF] cover?

This checklist covers 35 inspection items across 7 sections: Study Setup and Planning, Measurement System Verification, Data Collection, Normality and Statistical Control Verification, Capability Index Calculation and Results, Documentation and Approval, Continuous Improvement and Follow-Up. It is designed for manufacturing qa operations and compliance.

How often should this checklist be completed?

This checklist should be completed per event. Each completion takes approximately 45-75 minutes.

Who should use this Process Capability Study Inspection Checklist [FREE PDF]?

This checklist is designed for QA Engineer professionals in the manufacturing qa industry. It can be used for self-assessments, team audits, and regulatory compliance documentation.

Can I download this checklist as a PDF?

Yes, this checklist is available as a free PDF download. You can also use it digitally in the POPProbe mobile app for real-time data capture, photo documentation, and automatic reporting.

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