1 Scope
1.1 This part of GB/T 2828 specifies a system for sampling inspection by attribute. This part uses terms for Acceptance Quality Limit (AQL) for inspection.
Purpose of this part is to use lot non acceptance to make the Supplier feel the pressure both economically and psychologically, so as to make the Supplier at least keep the process average at the same level with the specified acceptance quality limit, and provide an upper limit for the risk of accepting low-quality lot on occasion by the User. Sampling scheme designated in this part of GB/T 2828 may be used for the following inspection (but not limited to it);
——Final products;
——Spare parts and materials;
——Operation;
——Goods in process;
——stock;
——Maintenance operation;
——Data or record;
——Management procedure
1.2 These sampling schemes are mainly used for lots of the continuous series. Length of the continuous series lot shall be long enough to allow using transition rules (see 9.3).
These rules are:
a) As soon as quality pauperization is discovered, provide protection for the user by transferring them to tightened inspection or suspending sampling inspection;
b) If the consistent good quality is obtained and confirmed by the responsible authorities, and reduce survey fees by transferring them to reduced inspection to provide an encouragement.
Sampling schemes of this part could also be used for the inspection of isolated lots, in order to find a sampling scheme, which could provide the expected protection, suggest the user in particular to refer to characteristic curves of random inspection for the sampling scheme. (See 12.1). The user could limit quality (LQ) retrieval sampling schemes given in GB/T 15239-1994.
Contents
Foreword I
1 Scope
2 Normative References
3 Terms, Definitions and Symbols
4 Representation of Nonconformity
5 Acceptance Quality Limit (AQL)
6 Submission of Sampling Items
7 Acceptance and Non-acceptance
8 Sample Drawing
9 Normal Inspection, Tightened Inspection and Reduced Inspection
10 Sampling Plan
11 Determination of Acceptability
12 Further Information of Values
13 Single Sampling Plan of Fractional Acceptance Number (for Option)
Appendix A (Informative) Examples for Unfixed Sampling Plan (II Level, AQL =1% Nonconforming Item)
References