What is PPAP?

PPAP (Production Part Approval Process) is the approval process confirming the series readiness of a part. In the industrial environment, it is used to manage quality risks systematically and make decisions traceable.

Scientific background

The methodological foundation is based on statistical and process-oriented concepts. Central is the evidence package for product and process conformity submitted to the customer. CT data can supplement these systems with internal component information and thereby increase evidence quality.

Relevant key metrics

Effectiveness of the method against defined KPIs and target values.
Reaction time between deviation detection and stable correction.
Sustainability of measures across multiple production cycles.

Standards and thresholds

Standards: AIAG PPAP (PPAP-4, 4th Edition, 2nd Printing, published Nov 2009) as well as VDA Volume 2 (6th revised edition, 04/2020).
Typical thresholds (in practice): Release only after a complete evidence package (PSW) and required capability status (often Cpk at least 1.33 for relevant features).
Validity: Submission level (1–5) and evidence scope are defined by the customer.

Application in industrial practice

Risk reduction during development and series ramp-up.
Standardised decision processes across functions and sites.
Linking quality-related evidence to customer requirements.

Sources and reference date

AIAG PPAP, product code PPAP-4, 4th Edition, 2nd Printing (published Nov 2009).
VDA Volume 2, 6th revised edition (04/2020).
Reference date: February 2026.