Meaning
Alphanumeric designation assigned within statistical sampling standards links lot size ranges to specific sample size tables. The code letter governs sample extraction counts in acceptance sampling schemes such as ISO 2859-1 or ANSI/ASQ Z1.4. It establishes the mandatory number of units pulled for testing based on batch volume and chosen inspection level.
The designation stops applying once sample size determination completes and inspection tables yield actual acceptance numbers.
Table Reference
Quality plans list designated letters alongside lot size brackets in master inspection documentation. Inspectors locate batch sizes on standard master tables to pull the correct character. Drawing letter J for a five thousand unit lot sets sample sizes at eighty pieces under normal single sampling schedules.
Operational Impact
Assigning an incorrect character alters statistical confidence levels across quality audits. Selecting code letter H instead of letter K reduces sample sizes from two hundred units to fifty units, increasing buyer risk. Sub-sampling errors pass defective lots through receiving docks into assembly lines.
Dispute Resolution
Purchase order disputes involve cross-verifying table characters written on final inspection certificates against master standard tables. Contract auditors check lot size rows to verify compliance. Writing an unauthorized code letter invalidates sample results and reinstates buyer inspection rights.
