1、AmericAn nAtionAl StAndArdAMERICAN SOCIETY FOR QUALITY600 N. PLANKINTON AVENUEMILWAUKEE, WI 53203-2914ASQ/ANSI S3 2012An attribute chain sampling programiiiASQ/ANSI S3 2012AmericAn nAtionAl StAndArdAn attribute chain sampling programApproved as an American National Standard by: American Society for
2、Quality Standards CommitteeMay 18, 2012An attribute chain sampling program provides procedures and properties for plans that can contribute to reducing inspection and improving performance characteristics of sampling inspection. The standard can be used alone or in conjunction with ANSI/ASQ Z 1.4 an
3、d ANSI/ISO/ASQ 2859-1.American National Standards: An American National Standard implies a consensus of those substantially concerned with its scope and provisions. An American National Standard is intended as a guide to aid the manufacturer, the consumer, and the general public. The existence of an
4、 American National Standard does not in any respect preclude anyone, whether he or she has approved the standard or not, from manufacturing, purchasing, or using products, processes, or procedures not conforming to the standard. American National Standards are subject to periodic review and users ar
5、e cautioned to obtain the latest information.Caution Notice: This American National Standard may be revised or withdrawn at any time. The procedures of the American National Standards Institute require that action be taken to reaffirm, revise, or withdraw this standard no later than five years from
6、the date of publication. Purchasers of American National Standards may receive current information on all standards by calling or writing the American National Standards Institute.ASQ/ANSI S3 2012iv 2012 by ASQAll rights reserved. No part of this publication may be reproduced in any form, in an elec
7、tronic retrieval system or otherwise, without the prior written permission of the publisher. Copyright Protection Notice for the ASQ/ANSI S3 2012 Standard. This standard is subject to copyright claims of ANSI and ASQ. Not for resale. No part of this publication may be reproduced in any form, includi
8、ng an electronic retrieval system, without the prior written permission of ASQ. All requests pertaining to the ASQ/ANSI S3 2012 Standard should be submitted to ASQ.note: As used in this document, the term “International Standard” refers to the American National Standard adoption of this and other In
9、ternational Standards.ASQ will consider requests for change and information on the submittal of such requests regarding this Standard. All requests should be in writing to the attention of the Standards administrator at the address below.ASQ mission: The American Society for Quality advances individ
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13、TED DOCUMENTvASQ/ANSI S3 2012Also available from ASQ Quality Press:ASQ/ANSI S1-2012: An attribute skip-lot sampling programANSI/ASQ Z1.4-2008: Sampling Procedures and Tables for Inspection by AttributesANSI/ASQ Z1.9-2008: Sampling Procedures and Tables for Inspection by Variables for Percent Nonconf
14、ormingANSI/ISO/ASQ 2859-1:1999: Sampling procedures for inspection by attributes Part 1: Sampling schemes indexed by acceptance quality limit (AQL) for lot-by-lot inspectionANSI/ISO/ASQ 2859-4:2002: Sampling procedures for inspection by attributes Part 4: Procedures for assessment of declared qualit
15、y levelsANSI/ISO/ASQ Q9001-2008: Quality management systems RequirementsThe Handbook of Applied Acceptance Sampling: Plans, Procedures, and Principles Kenneth S. StephensZero Acceptance Number Sampling Plans, Fifth Edition Nicholas L. SquegliaThe Certified Quality Engineer Handbook, Third Edition Co
16、nnie M. Borror, editorThe Desk Reference of Statistical Quality Methods, Second Edition Mark L. CrossleyThe Quality Toolbox, Second Edition Nancy R. TagueThe Certified Six Sigma Green Belt Handbook Roderick A. Munro, Matthew J. Maio, Mohamed B. Nawaz, Govindarajan Ramu, and Daniel J. ZrymiakThe Cert
17、ified Manager of Quality / Organizational Excellence Handbook: Third Edition Russell T. Westcott, editorRoot Cause Analysis: Simplified Tools and Techniques, Second Edition Bjrn Andersen and Tom FagerhaugThe Certified Six Sigma Black Belt Handbook, Second Edition T.M. Kubiak and Donald W. BenbowTo r
18、equest a complimentary catalog of ASQ Quality Press publications, call 800-248-1946, or visit our Web site at http:/www.asq.org/quality-press.(This page intentionally left blank.)contentsintroduction viii1 Scope and purpose .11.1 Field of application 12 references 23 terms and definitions .23.1 Chai
19、n sampling inspection .23.2 Lot-by-lot inspection 23.3 Essentially continuous production 34 Supplier and product qualification .34.1 Supplier qualification 34.2 Product qualification .35 chain sampling procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
20、 . . . . . . . . . . . . . . . . . . . .36 chain sampling evaluation .66.1 OC curves and tables of operating characteristics (performance) 66.2 Table useful for AQL and LQL matching 76.3 Determination of AOQL for chain sampling plans 76.4 Fractional acceptance numbers 77 Supplier responsibilities .9
21、8 inspection agency and responsible authority responsibilities 9Annex A operating characteristics of chain sampling plan .10Bibliography .39viiASQ/ANSI S3 2012viiiintroductionThis publication is intended as a stand-alone standard to provide a source of a limited selection of chain sampling plans and
22、 their operating characteristics (OC), and to assist in the application of the chain sampling procedures while performing attribute, lot-by-lot, single sampling inspection. It is also intended to serve as a further explanation of and to provide the operating characteristics for the fractional accept
23、ance number plans for single sampling that are included in ANSI/ISO/ASQ 2859-1: Sampling procedures for inspection by attributes Part 1: Sampling schemes indexed by acceptance quality limit (AQL) for lot-by-lot inspection. Fractional acceptance number plans are essentially chain sampling procedures
24、and are provided in ISO 2859-1 as an optional procedure in cases where the combination of sample size code letters and AQLs result in plans between the 0 and 1 acceptance numbers. It is expected that this optional procedure will be included in ANSI/ASQ Z1.4 in a subsequent revision. Chain sampling p
25、lans are ideally suited to replace zero (0) acceptance number plans for single sampling during essentially continuous lot submissions under steady production. As shown herein their operating characteristics fall between those of c = 0 and c = 1 sampling plans, hence the name used in ANSI/ISO/ASQ 285
26、9-1 plans.1ASQ/ANSI S3 20121 Scope and purposeThis standard describes the process of chain sampling, the theory, applications, plans for use, operating (performance) characteristics, and the utility of chain sampling as compared to single sampling via the operating characteristics. The purpose of th
27、is standard is to provide the procedures for a collection of sample sizes as well as to present the static operating characteristics for the plans presented, for use of the chain sampling technique. There is no direct indexing of the plans such as that of acceptance quality limit (AQL) used in ANSI/
28、ASQ Z1.4 and ANSI/ISO/ASQ 2859-1. However, the complete OC are presented in both table and OC curve form for every sample size included. Furthermore, formulations are provided to compute the average outgoing quality limit (AOQL) for any of the chain sampling plans presented, related to the five valu
29、es of the parameter, i, the sample size, n, and the lot size N, being applied. Those interested in using chain sampling to replace attribute sampling plans indexed either by AQL or limiting quality level (LQL) as given in ANSI/ASQ Z1.4 and ANSI/ISO/ASQ 2859-1, may select an appropriate plan from thi
30、s standard by consulting the table of operating characteristics for the various sample sizes to find a plan with pat the desired AQL with probability of acceptance (Pa) equal to 0.95, 0.98, etc and/or the desired LQL at Pa equal to 0.10, Table 1 is also given herein that summarizes the p0,95 and the
31、 p0,10values forcombinations of the parameters, n and i, to assist with this possible interest. 1.1 Field of applicationSampling plans designated in this publication are applicable, but not limited to, inspection of the following:a) end items such as complete units or sub-assemblies;b) components an
32、d raw materials;c) operations or services;d) materials in process;e) maintenance operations;f) data or records;g) administrative procedures.These plans are intended primarily to be used for a continuing series of lots or batches (operations), essentially a series of continuous supply, preferably in
33、order of production (service). It is recommended that they not be used for isolated lots. Normally, lots or batches (operations) are expected to be of essentially the same satisfactory quality. They are particularly applicable to situations where the customer (receiving the inspected lots) has some
34、degree of confidence in the integrity of the producer/supplier. Chain sampling plans are particularly suited to situations satisfying the preceding conditions and involving destructive, complex, and/or costly tests for which a relatively small sample is desired yielding good quality discrimination.
35、They are additionally useful for achieving better discrimination (than single sampling plans in particular) in situations associated with assuring tighter quality levels (with comparably larger sample sizes). A special purpose of chain sampling is to achieve a more favorable international StandardAS
36、Q/ANSI S3 20122operating (performance) characteristic than that of single sampling, especially with an acceptance number, c, of zero for relatively small samples as mentioned above. The situations of supply should be suitable to the use of cumulative results of two or more samples from consecutive l
37、ots in making an acceptance/rejection decision on the current lot.This publication shall be used only for characteristics inspected by attributes as designated in publication ANSI/ASQ Z1.4. With respect to the inspection of multiple characteristics, the chain sampling procedures will follow the same
38、 principles used in ANSI/ASQ Z1.4. This standard may be referenced in a purchasing or specification contract, inspection instructions, or other contractual and/or operational documents.2 referencesBasic definitions may be found in the following standards:1. ANSI/ISO/ASQ 3534-2: Statistics Vocabulary
39、 and symbols Part 2: Applied Statistics2. ANSI/ASQ S2: Introduction to Attribute Sampling3. ANSI/ASQ Z1.4: Sampling Procedures and Tables for Inspection by Attributes4. ANSI/ISO/ASQ 2859-1: Sampling procedures for inspection by attributes Part 1: Sampling schemes indexed by acceptance quality limit
40、(AQL) for lot-by-lot inspection3 terms and definitionsThe terminology and definitions are in accordance with ANSI/ISO/ASQ 3534-2, ANSI/ASQ Z1.4, and ANSI/ISO/ASQ 2859-1.3.1 chain sampling inspection An acceptance sampling procedure in which the criteria for acceptance of the current lot, in lot-by-l
41、ot inspection of an essentially continuous production sequence, is governed by the sampling results of the lot sampled and those of a specified number of preceding consecutive lot samples. It is a member of a class of procedures referred to as cumulative results sampling inspection. Chain sampling,
42、in its simplest form, is designated ChSP-1, and this standard is limited to plans of this form. Individual lots and samples are considered as links in a chain, hence, the name, chain sampling. Considerable extensions and variations have been developed to form a larger family of chain sampling and cu
43、mulative-results inspection plans and are available in the literature. 3.2 lot-by-lot inspection Inspection of product submitted in a series of lots. A sample is selected from each lot and inspected for the designated characteristic(s) using attribute inspection procedures. 3ASQ/ANSI S3 20123.3 esse
44、ntially continuous production Production that is at a steady rate. Production shall be considered essentially continuous if at least one lot of product is submitted for inspection at a production frequency as agreed to by both the supplier and the responsible authority (see ANSI/ASQ Z1.4, Section 1.
45、1). If no production frequency is specified, at least one lot shall be submitted each month. Product shipped to other parties or products of a similar nature shall be considered in the determination of essentially continuous production unless excluded by both the supplier and responsible authority.4
46、 Supplier and product qualification4.1 Supplier qualificationThe supplier shall:a) Have implemented and maintained a documented system for controlling product quality and design changes so as to assure that the quality of the product is of an acceptable level and that this level is stable. Using cum
47、ulative results such as in chain sampling requires that the quality of lots from which sample results are cumulated to make an accept/reject decision on the current lot shall be stable. b) Have instituted a system which is capable of detecting and correcting shifts in quality levels, and monitoring
48、changes which may adversely affect quality and acceptance/rejection decisions using chain sampling.c) Not have experienced an organizational change that might adversely affect quality.4.2 Product qualificationThe product shall have met all of the following requirements:a) Be of stable design.b) Have
49、 been manufactured on an essentially continuous basis for a period mutually agreed to by both the supplier and responsible authority. If no period is specified, the period shall be six months. Whenever production is held pending sample approval, only the time period after approval and resumption of product shall be included.5 chain sampling procedures The main purpose of chain sampling procedures (ChSP) is to achieve a more favorable operating characteristic than that of single sampling, especially with an acceptance number c of zero for relatively small
