Prozanta Template
Control plan
Systematic quality control with measurement points and reaction plans
Process / Part no.:
Customer:
Rev. date / no.:
Product / Process type
Prepared by
Approved by
Valid from
How to use this template
The control plan defines precisely what is controlled in a process, when, with what, by whom — and what happens if the control shows a deviation. It is the foundation for systematic quality management and a requirement in IATF 16949 and ISO 9001. A control plan is a living document: it is updated on process changes.
P — Product control
- Control of the physical output: dimensions, tolerances, visual inspection
- E.g. diameter 25 mm ± 0.1 mm
C — Process control
- Control of the process input parameters: temperature, pressure, speed
- E.g. melt temperature 185°C ± 5°C
S — System control
- Audit and verification of systems and documentation
- E.g. weekly check of calibration status
Step by step
- List all process steps that can affect product quality — a process flow diagram is a useful input.
- For each step: identify the characteristic that is critical (what can go wrong and what is the tolerance?).
- Choose the measurement method and equipment — state calibration requirements and sample size.
- Set the frequency: how often depends on the process's stability — unstable processes need tighter control.
- Define the reaction plan: what happens specifically if a control shows a deviation? Who is it escalated to?
- Update the control plan when the process changes — an outdated control plan gives false confidence.
Watch out
- Only control what can actually deviate and affect the customer — too many control points create blindness.
- A sample is a compromise: the more critical the characteristic, the larger the sample (or 100% control).
- The reaction plan is just as important as the control itself — without a plan, a deviation leads to panic and arbitrary actions.
Example
Process step: welding. Characteristic: tensile strength ≥ 350 MPa (P-type). Method: tensile test. Sample: n=3 per batch. Frequency: 1/shift. Reaction: stop production, quarantine the latest batch, call the welding technician.
Method: AIAG Control Plan (CP-1), 1st edition (2024). The control plan was separated out of the APQP manual in March 2024 and now has its own. Used in IATF 16949, ISO 9001 and general quality management; it pairs with the FMEA, so each control matches a failure mode there.
Control plan
| # | Process step | Characteristic controlled | Type | Specification / Tolerance | Measurement method / Equipment | Sample size | Frequency | Who controls | Recording | Reaction plan on deviation |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | P/C/S | |||||||||
| 2 | P/C/S | |||||||||
| 3 | P/C/S | |||||||||
| 4 | P/C/S | |||||||||
| 5 | P/C/S | |||||||||
| 6 | P/C/S | |||||||||
| 7 | P/C/S | |||||||||
| 8 | P/C/S | |||||||||
| 9 | P/C/S | |||||||||
| 10 | P/C/S |
Type: P = Product control, C = Process control, S = System control
Reaction plans — what to do on a deviation
| Control point (from plan) | Deviation type | Immediate action | Long-term correction | Escalate to |
|---|---|---|---|---|