What is SPC?

SPC (Statistical Process Control) is the statistical monitoring of processes using control charts. 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 separation of random variation from special-cause variation to enable early reaction. 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: ISO 7870-1:2019, ISO 7870-2:2023 as well as AIAG SPC (SPC-3, Version 2, published Jul 2005).
Typical thresholds (in practice): Control limits at ±3 sigma; process capability for series release often Cpk at least 1.33.
Validity: Rule set and capability targets are defined per characteristic and 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

ISO 7870-1:2019 (General guidelines).
ISO 7870-2:2023 (Shewhart control charts).
AIAG SPC, product code SPC-3, Version 2 (published Jul 2005).
Reference date: February 2026.