Production Part Approval Process


Production Part Approval Process ("PPAP") is the industry standard that ensures engineering design and specification requirements are met. The purpose of PPAP is to verify whether the supplier’s manufacturing process is capable of consistently producing product meeting all product engineering design and specifications, and demonstrate the developed packaging eliminates damage during transportation, handling, and storage.

PPAP Workbook

All documents must be submitted in Westport Fuel Systems accepted format. Download the Production Part Approval Process (PPAP) for a detailed explanation.

Associated Templates Are Listed below Each Step.

  1. Design Records Drawings
  2. Engineering Change Documents (If Any) Change Documents
  3. Customer Engineering Approval
  4. Design FMEA
  5. Process Flow Diagrams Process Flow Charts
  6. Process Fmea Process-potential Failure Mode and Effects Analysis
  7. Control Plan Process/Product Control Plan (Cp)
  8. Measurement System Analysis Studies Gage R&R, Bias, Linearity and Stability
  9. Dimensional Results Report Dimensional Layout
  10. Material, Performance Test Results Gage R&R, Bias, Linearity and Stability
  11. Initial Process Study Capability (Cpk/Ppk) Studies
  12. Laboratory Scope and Accreditation 17025 Certification
  13. Aar Appearance Approval Report
  14. Sample Parts PPAP Samples 15. Master Sample
  15. Master Sample
  16. Checking Aids
  17. Record of Compliance
  18. Psw Part Submission Warrant
  19. IMDS
  20. Packaging


PPAP Checklist

The checklist indicates the elements required by Westport for the Production Part Approval Process.

The submission level pertains to only what must be submitted. All of the elements must be completed by the supplier unless you explicitly waive them.

S = submit to the customer
R= Retain at the manufacturing location and make available to the customer if requested
* = Retain at the manufacturing location and submit to the customer if requested

Documentation Definitions

Each submission element is described in detail below. Westport has outlined specific requirements for each element.


Templates have been included for your use. These are AIAG (Automotive Industry Action Group) standard templates. Manuals relating to these activities are available through AIAG website at If your organization uses non AIAG standard templates for these activities, please forward a blank copy to Westport for approval prior to proceeding with PPAP activities.

Part Submission Warrant (PSW)

The Part Submission Warrant is required for each submission and must be completed and forwarded with PPAP package.

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