ISO 14253-1:2017 establishes standardized decision rules for verifying the conformity or nonconformity of workpieces and measuring equipment with specifications, incorporating measurement uncertainty. It defines acceptance and rejection zones based on a default 95% confidence level, reducing disputes by clearly addressing borderline measurements. For detailed information, visit ISO .
This is the when uncertainty is known.
ISO 14253-1:2017(en), Geometrical product specifications (GPS) — Inspection by measurement of workpieces and measuring equipment — Part 1: Decision rules for verifying conformity or nonconformity with specifications INTERNATIONAL STANDARD ISO 14253 1.pdf
If the measured value lies between these outer limits (i.e., within (U) of the specification limit but on the “wrong” side), the standard says — it is indeterminate. INTERNATIONAL STANDARD ISO 14253 1.pdf