The Production Part Approval Process (PPAP) is used to establish confidence in component suppliers and their production process.
It provides customers with evidence that:
Component suppliers have understood their requirements.
The product meets customers requirements.
The production process is capable of consistently producing conforming product.

PPAP is an important part of the product development process, allowing producers to evaluate the components and sub-systems which they receive from suppliers, and establishing confidence in the supplier’s management systems.
The PPAP process is designed to demonstrate that the component supplier has developed their design and production process to meet the customer’s requirements, minimising the risk of failure by effective use of APQP. Requests for part approval must therefore be supported by-
Purpose:
Defines Generic requirements for production for Production Part Approval including production and bulk materials, The purpose of PPAP is to Determine if all customer engineering design record & specification requirements are properly understood by the organisation and that the manufacturing processes as potential to produce the product consistently meeting these requirements during an actual production run at the quoted production rate.
PPAP Approval
The result of this process is a series of documents gathered in one specific location (a binder or electronically) called the “PPAP Package”. The PPAP package is a series of documents which need a formal approval by the supplier and customer. The form that summarizes this package is called PSW (Part Submission Warrant). The approval of the PSW indicates that the supplier responsible person (usually the Quality Engineer) has reviewed this package and that the customer has not identified any issues that would prevent its approbation.
The documentation on the PPAP package is closely related to the Advanced Product Quality Planning process (APQP) used during the design and development of new vehicles and component systems to reduce the risk of unexpected failure due to errors in design and manufacture. The PPAP manual is published by the Automotive Industry Action Group (AIAG), www.aiag.org and specifies generic requirements for obtaining PPAP approvals. Additional customer specific requirements may be imposed by particular clients (vehicle manufacturers) and incorporated in the purchasing contracts. Details of ‘customer specific’ requirements may be found on the International Automotive Task Force [[IAT website www.iatfglobaloversight.org. or supplier portals provided by the vehicle manufacturers. A new website, developed by Customer Specific Requirements, LLC http://customerspecifics.com has been created to help solve problems associated with the distribution and accessibility of customer specific requirements.
Suppliers are required to obtain PPAP approval from the vehicle manufacturers whenever a new or modified component is introduced to production, or the manufacturing process is changed. Obtaining approval requires the supplier to provide sample parts and documentary evidence showing that:
1) The clients requirements have been understood
2) The product supplied meets those requirements
3) The process (including sub suppliers) is capable of producing conforming product
4) The production control plan and quality management system will prevent non-conforming product reaching the client or compromising the safety and reliability of finished vehicles
Production Part Approval Process (PPAP) may be required for all components and materials incorporated in the finished product, and may also be required if components are processed by external sub-contractors.
PPAP is the confirmation that the product meets the customer requirements for series production. The PPAP will be considered signed when a full PSW is approved by your customer and added to the PPAP folder. The PSW would always be supported with a ISIR but the PPAP is only considered approved when a FULL PSW is endorsed with and ISIR.
In essence the PSW and ISIR are part of PPAP or VDA and can even be outside of PPAP in cases such as first off tool parts which should be submitted in most cases with a PSW and ISIR but will not be approved in PPAP until series conditions are met.
The ISIR is the part of the PPAP which includes the product ballooned drawing, layout and the capability study (Cpk’s). It may sometimes be separately requested by the customer annually or in the event of repeating nonconformance.
The Verband der Automobilindustrie (VDA) is an interest group of the German automobile industry,based in Frankfurt, Germany.