PPAP review checklist

A complete and current process FMEA should identify all potential failure modes at each process step, with corresponding severity, occurrence, and detection ratings. Verify that high-risk priority numbers (RPNs) have recommended actions with responsibility assignments. Check that the process FMEA reflects the actual manufacturing process shown in the flow diagram and that it’s been updated to include any recent process changes or corrective actions from previous quality issues.

The most common reasons for PPAP rejection include inconsistencies between documents (like mismatches between the control plan and process flow), missing or incomplete dimensional results, inadequate measurement system analysis studies, and insufficient process capability data. Also watch for outdated revision levels, incomplete design or process FMEAs, and missing customer-specific requirements. Identifying these issues during review prevents costly rejection cycles and production delays.

When reviewing an unfamiliar product’s PPAP, start by understanding the product’s function and critical requirements. Request a brief overview from the design or process engineer. Focus on consistency across documents rather than technical details—verify that special characteristics in drawings appear in the FMEA, control plan, and dimensional results. Check that all required PPAP elements are present and properly completed. When in doubt about technical aspects, consult with experts rather than approving incomplete submissions.

Use interim approval when a PPAP submission has minor deficiencies that don’t affect form, fit, or function, but still need correction. This approach is appropriate when production timing is critical and the supplier has a clear, time-bound action plan to address the issues. Specify exactly which elements need improvement, set a firm deadline for resubmission (typically 90 days or less), and clearly define any quantity restrictions during the interim period. Never grant interim approval for issues that could impact product safety or regulatory compliance.