ISO 3951-1:2022, Sampling Procedures for Inspection by Variables - Part 1

Purpose: ISO (International Organization for Standardization) has published the third edition of ISO 3951-1:2022, <i>Sampling Procedures for Inspection by Variables-Part 1</i>. ISO 3951-1 is an AQL (Acceptable Quality Limit) type sampling scheme, and incorporates switching rules to move among normal, tightened, and reduced inspections. This paper examines the contents of ISO 3951-1:2022 and analyzes its characteristics.Methods: The contents of ISO 3951-1:2022 and ISO 3951-1:2013 (the second edition of ISO 3951-1) are compared and analyzed in detail. The comparisons of ISO 3951-1:2022 and ISO 2859-1:2013 (the latest edition of <i>Sampling Procedures for Inspection by Attributes-Part I</i>) are also performed.Results: The main changes of ISO 3951-1:2022 are as follows: i) procedures have been introduced to accommodate measurement uncertainty, ii) many of sampling plans are adjusted to improve the match between their OC (operating characteristic) curves and the OC curves of the corresponding plans of ISO 2859-1, iii) the form p* for determining the acceptance of the lot is extended to all ranges of AQL and code letter values.Conclusion: ISO 3951-1:2022 cancels and replaces ISO 3951-1:2013, which has been technically revised. KS Q ISO 3951-1:2019 that is Korean version of ISO 3951-1 was established as a Korean standard by conforming to ISO 3951-1:2013. Therefore, we need to revise it to ISO 3951-1:2022, as soon as possible.