Quality Assurance

Multi-AQL Inspection Thresholds (Critical / Major / Minor)

Three AQLs, one sample, and the lot fails on whichever breaks first. The tightest utilisation is the number that decides the shipment.

Sampling Plan ISO 2859-1
pieces
%
%
%
Findings Defects observed
no.
no.
no.

Tightest Limit Consumed

— %

Worst of the three classes against its own accept number

Class Thresholds

Major Accept Number
— no.
Major Reject Number
— no.
Minor Accept Number
— no.
Minor Reject Number
— no.
Critical Reject Number
— no.
Total Defect Rate in Sample
— %

Utilisation at or above 100% means that class is at or past its accept number and the lot fails. Critical defects normally carry an AQL of zero, so a single one rejects. The published ISO 2859-1 master table governs any contractual inspection — treat these accept numbers as a planning approximation and confirm against the table and the agreed inspection level.

Multi-AQL Inspection Thresholds (Critical / Major / Minor) — free, with the formula and a worked example, at Textile School.