The Production Part Approval Process (PPAP) is a formal methodology used in supply chain management to establish confidence in a supplier’s production methods and component quality. This standardized process ensures that a manufacturer can consistently produce a part that meets all customer engineering design records and specifications. While primarily employed in the automotive industry, its use has spread to aerospace, medical, and other sectors where product integrity and supply chain stability are important. PPAP acts as a final gate before full-scale production begins, validating that both the product and the manufacturing process are ready for mass output.
Defining the Production Part Approval Process
PPAP is a structured process requiring a supplier to formally confirm they have understood all requirements for a new or revised part. The process outcome is a documented demonstration that the supplier’s production methods can consistently produce the product during an actual production run at the quoted rate. This formalized system is governed by the Automotive Industry Action Group (AIAG), which provides standardized forms and common terminology across the industry.
PPAP is considered a core tool within the Advanced Product Quality Planning (APQP) framework. It focuses on the final stage of APQP, the Product and Process Validation phase. PPAP provides documented evidence that the manufacturing process is capable of mass production, serving as the supplier’s formal declaration that all design and specification requirements have been met.
When PPAP Submissions Are Required
A new or revised PPAP submission is required anytime a change occurs that could affect the fit, form, function, performance, or quality of a part. The most common trigger is the introduction of an entirely new part or product. Suppliers must also seek customer re-approval when changes are made to existing parts.
Common Submission Triggers
A formal resubmission is required for the following changes:
Engineering changes to the design record or specifications.
Modifications to the manufacturing process, such as changes in tooling, process flow, or machinery.
Changes in the source of raw materials or sub-components.
A change in the manufacturing location.
If a part has been inactive for an extended period, typically 12 months or more, before production resumes.
The Purpose and Value of PPAP
The purpose of PPAP is to mitigate risk for the customer by ensuring quality is built into the product and process from the beginning. It requires the supplier to prove capability before a large volume of parts is manufactured and shipped. This proactive approach prevents costly errors, rework, and potential production line shutdowns caused by non-conforming parts discovered late in the process.
The documentation package serves as a verifiable record that the supplier understands and can meet all technical requirements. By demonstrating that the production process is capable of meeting specifications, PPAP establishes trust between the supplier and the customer. This leads to a more reliable supply chain and higher product quality.
The Core Components of a PPAP Submission
The PPAP submission package is a collection of documents and physical samples that provide objective evidence of compliance with customer requirements. The package is summarized by the Part Submission Warrant (PSW), a formal declaration signed by the supplier confirming all requirements have been met. The supporting documentation is grouped into three main evidentiary categories.
Design Records and Change Control
This category focuses on design records and change control. It includes copies of customer and supplier drawings, often referred to as ballooned drawings, which are marked with all measurements and specifications. Authorized engineering change documents are included to show that the latest design revisions have been implemented. A Design Failure Mode and Effects Analysis (DFMEA) is also required, documenting the systematic analysis of potential design failures.
Process Documentation
This section details the documentation governing how the part is manufactured. It requires a Process Flow Diagram, which maps every step of the manufacturing process from raw material receipt to final shipment. This is supported by the Process Failure Mode and Effects Analysis (PFMEA), which analyzes potential failure points within the manufacturing process. Finally, the Control Plan outlines the methods used to control product and process characteristics at each step, confirming a controlled and repeatable system for production.
Measurement and Testing Results
This category contains the physical proof of conformity. It includes Dimensional Results, providing measurements for every feature on the part drawing to confirm they are within tolerance. Material and performance test results verify chemical, physical, or functional requirements. Initial Process Studies are also supplied to demonstrate the statistical capability of the production process for specific characteristics. These documents prove that the first production run yielded conforming parts.
Understanding PPAP Submission Levels
The amount of documentation a supplier must submit depends on the agreed-upon PPAP Submission Level, which tailors the process based on the part’s complexity and risk. The AIAG defines five standard levels that determine whether documentation must be submitted to the customer, retained at the supplier, or retained and available for review.
The Five Submission Levels
Level 1: Only the Part Submission Warrant (PSW) is submitted to the customer; all supporting data is retained at the supplier.
Level 2: PSW and limited supporting data are submitted to the customer.
Level 3: PSW, product samples, and complete supporting data are physically submitted to the customer for review. This is the typical default requirement for most automotive customers.
Level 4: PSW and other specific requirements are defined by the customer and submitted.
Level 5: The supplier retains all documentation and samples but makes them available for a thorough on-site review at the manufacturing facility.
The customer determines the submission level based on factors such as the part’s criticality, the supplier’s history, or the complexity of the design. These varying levels ensure the administrative burden matches the technical risk of the component.
The Production Part Approval Process is a foundational quality management tool that codifies supplier accountability in high-stakes manufacturing environments. It is an evidence-based method for ensuring product integrity and supply chain stability. By validating both the product design and the manufacturing process, PPAP guarantees that a supplier can consistently deliver conforming parts.