1、Designation: E2910 12Standard Guide forPreferred Methods for Acceptance of Product1This standard is issued under the fixed designation E2910; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in pa
2、rentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide establishes lot or batch and continuoussampling plans using MIL-STD-1916 as a basis. It representsan alternative sampling approach to at
3、tributes sampling (MIL-STD-105E, same as E2234), variables sampling (MIL-STD-414, E2762), and continuous sampling (MIL-STD-1235B,E2819).1.2 This guide provides the sampling plans of MIL-STD-1916 in ASTM format for use by ASTM committees andothers. It recognizes the continuing usage of MIL-STD-1916 i
4、nindustries supported by ASTM. Most of the original text inMIL-STD-1916 is preserved in Sections 4-6 of this guide. Theoriginal wording of “Government” in MIL-STD-1916 has beenchanged to “consumer”, and “contractor” has been changed to“producer” to make this standard more generic.1.3 PurposeTo encou
5、rage producers supplying goods andservices to its consumers to submit efficient and effectiveprocess control (prevention) procedures in place of prescribedsampling requirements. The goal is to support the movementaway from an AQL-based inspection (detection) strategy toimplementation of an effective
6、 prevention-based strategy in-cluding a comprehensive quality system, continuous improve-ment and a partnership with the consumer. The underlyingtheme is a partnership between consumer and the producer,with the requisite competence of both parties, and a clearmutual benefit from processes capable of
7、 consistently highquality products and services. The objective is to create anatmosphere where every noncompliance is an opportunity forcorrective action and improvement rather than one whereacceptable quality levels are the contractually sufficient goals.1.4 This standard does not purport to addres
8、s all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E456 Terminology
9、 Relating to Quality and StatisticsE2234 Practice for Sampling a Stream of Product by Attri-butes Indexed by AQLE2762 Practice for Sampling a Stream of Product by Vari-ables Indexed by AQLE2819 Practice for Single- and Multi-Level ContinuousSampling of a Stream of Product by Attributes Indexed byAQL
10、2.2 Other Standards:3MIL-STD-105E Sampling Procedures and Tables for In-spection by AttributesMIL-STD-1235B Single- and Multi-Level Continuous Sam-pling for AttributesMIL-STD-1916 DoD Preferred Methods for Acceptance ofProductMIL-STD-414 Sampling Procedures and Tables for Inspec-tion by Variables fo
11、r Percent Defective3. Terminology3.1 DefinitionsThe terminology defined in TerminologyE456 applies to this guide except as modified below.3.1.1 critical defect, na defect that judgment and experi-ence indicate would result in hazardous or unsafe conditionsfor individuals using, maintaining, or depen
12、ding upon theproduct, or a defect that judgment and experience indicate islikely to prevent performance of the function of a major enditem. E22343.1.2 inspection, nthe process of measuring, examining,testing, or otherwise comparing the unit of product with therequirements. E22343.1.3 major defect, n
13、a defect, other than critical, that islikely to result in failure, or to reduce materially the usabilityof the unit of product for its intended purpose. E22341This guide is under the jurisdiction of ASTM Committee E11 on Quality andStatistics and is the direct responsibility of Subcommittee E11.30 o
14、n StatisticalQuality Control.Current edition approved Dec. 1, 2012. Published February 2013. DOI: 10.1520/E2910-12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to t
15、he standards Document Summary page onthe ASTM website.3Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http:/dodssp.daps.dla.mil.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 1942
16、8-2959. United States13.1.4 minor defect, na defect that is not likely to reducematerially the usability of the unit of product for its intendedpurpose, or is a departure from established standards havinglittle bearing on the effective use or operation of the unit.E22343.1.5 non-conforming item, nan
17、 item containing at leastone non-conformity. E22343.1.6 production interval, na finite period of production,N items in length. E28193.1.6.1 DiscussionIn this guide, the production interval isa period of production under continuous sampling assumed toconsist of essentially homogeneous quality. It is
18、normally ashift; it can be a day if it is reasonably certain that shift changesdo not affect quality of product, but shall not be longer than aday.3.1.7 screening, n100 % inspection where all defectiveunits are removed from the production flow. E28193.1.7.1 DiscussionThe two terms, screening and 100
19、 %inspection, are used interchangeably in this practice.3.2 Definitions of Terms Specific to This Standard:3.2.1 acceptance, nthe act of an authorized representativeof the consumer by which the consumer, for itself or as a agentof another, assumes ownership of existing identified suppliedtendered or
20、 approves specific services rendered as partial orcomplete performance of the contract.3.2.2 contract quality assurance, nthe various functions,including inspection, performed by the consumer to determinewhether a producer has fulfilled the contract obligationspertaining to quality and quantity.3.2.
21、3 contract quality requirements, nthe technical re-quirements in the contract relating to the quality of the productor service and those contract clauses prescribing inspection,and other quality controls incumbent on the producer, to assurethat the product or service conforms to the contractual requ
22、ire-ments.3.2.4 critical characteristic, nsee critical defect.3.2.5 critical nonconforming unit, na unit of product thatfails to conform to specified requirements for one of morecritical characteristics.3.2.6 major characteristic, nsee major defect.3.2.7 major nonconforming unit, na unit of product
23、thatfails to conform to specified requirements for one or moremajor characteristics, but conforms to all critical characteris-tics.3.2.8 minor characteristic, nsee minor defect.3.2.9 minor nonconforming unit, na unit of product thatfails to conform to specified requirements of one or more minorchara
24、cteristics, but conforms to all critical and major charac-teristics.3.2.10 nonconformance, na departure from a specifiedrequirement for any characteristic.3.2.11 nonconforming unit, nsee non-conforming item.3.2.12 quality, nthe composite of material attributes in-cluding performance features and cha
25、racteristics of a productor service to satisfy a given need.3.2.13 quality assurance, na planned and systematic pat-tern of all actions necessary to provide adequate confidencethat adequate technical requirements are established; productsand services conform to established technical requirements;and
26、 satisfactory performance is achieved.3.2.14 quality audit, na systematic examination of the actsand decisions with respect to quality in order to independentlyverify or evaluate the operational requirements of the qualityprogram or the specification or contract requirements of theproduct or service
27、.3.2.15 quality program, na program which is developed,planned, and managed to carry out cost effectively all efforts toeffect the quality of materials and services from conceptthrough validation, full-scale development, production,deployment, and disposal.3.2.16 screening inspection, nsee screening
28、.3.2.17 traceability, nthe ability to trace the history, appli-cation or location of an item or activity, or similar items oractivities, by means of recorded identification.3.2.18 verification level (VL), nprescribes the level ofsignificance or utility of a characteristic to the user.3.2.18.1 Discus
29、sionThe amount of effort to assure confor-mance can be allocated on the basis of importance to the user.(Major characteristics will require more verification effort thanminor characteristics.) VL-VII requires the highest level ofeffort, and the effort decreases as the VL decreases to thelowest level
30、, VL-I.4. Summary of Practice4.1 Acceptance by Producer-Proposed Provisions:4.1.1 General:4.1.1.1 This standard, when referenced in the contract orproduct specifications, requires the producer to perform sam-pling inspection in accordance with paragraph 4.2 and theproduct specification. However, it
31、is recognized that samplinginspection alone does not control or improve quality. Productquality comes from proper product and process design andprocess control activities. When such activities are effective,sampling inspection is a redundant effort and an unnecessarycost. Producers that have an acce
32、ptable quality system andproven process controls on specific processes are encouragedto consider submitting alternate acceptance methods for one ormore contractually specified characteristics. In addition, pro-ducers that have a successful quality system and a history ofsuccessful process controls r
33、elevant to the products/servicesbeing procured in this contract, are encouraged to considersubmitting a systemic alternate acceptance method for all thecontractual sampling inspection requirements associated withparagraph 4.2.4.1.1.2 Submissions shall describe the alternate acceptancemethods, the sa
34、mpling inspection provision to be replaced, andan evaluation of the protection provided by the alternatemethods as compared with the inspection requirement to bereplaced. The alternate acceptance method shall include evi-dence of process control and capability during productiontogether with adequate
35、 criteria, measurement, and evaluationE2910 122procedures to maintain control of the process. The acceptabil-ity of the alternate acceptance methods is dependent upon theexistence of a quality system, the demonstration of its processfocus, and the availability of objective evidence of effective-ness
36、.4.1.2 Requirements and Procedures:4.1.2.1 Producers currently operating quality systems inaccordance with such models as ISO 9000, ANSI/ASQCQ9004, or others that are deemed satisfactory to the consumerrepresentative are qualified to apply for alternate acceptancemethods if demonstration of process
37、focus and objectiveevidence of effectiveness exists.4.1.2.2 The producer shall include in his request for ap-proval of an alternate acceptance method an assessment plan toperiodically verify process stability, capability, and other con-ditions under which the alternate acceptance method wasdeveloped
38、. The current minimum values of process capabilityare equivalent to a Cpk of 2.00 for critical characteristics, 1.33for major characteristics, and 1.00 for minor characteristics.Upon approval of the assessment plan, the producer mayreduce or eliminate inspection sampling when the plan criteriaare me
39、t or exceeded.4.1.3 Submission and Incorporation:4.1.3.1 SubmissionThere are two ways of submitting al-ternate acceptance methods:(1) Submission of individual alternate acceptance methodsfor one or more contractually specified sampling inspectionrequirements through the consumer quality assurance re
40、presen-tative (QAR) to the procuring contracting officer (PCO) forapproval at any time during the contract period of performance.(2) Submission of a systemic alternate acceptance methodto the PCO prior to contract being awarded. This pre-approvalallows the producer to adopt alternate acceptance meth
41、odsthroughout the length of the contract. After contract award,submissions of a systemic alternate acceptance method shouldbe made through the administrative contracting officer (ACO)to the PCO.4.1.3.2 IncorporationAll approved alternate acceptancemethods shall be incorporated into the producers man
42、ufactur-ing and quality program plans or other vehicles acceptable tothe contracting agency, as applicable.4.1.4 Withdrawal of Approval of AlternatesThe consumerreserves the right to withdraw approval of alternate acceptancemethods that are determined to provide less assurance ofquality than the ins
43、pection requirements originally specified orwhen the inability to maintain process stability and capabilityover time becomes apparent.4.2 Acceptance by Tables:4.2.1 Preferred Sampling PlansThis standard establishesthree sets of matched sampling plans for the sampling inspec-tion of product submitted
44、 to the consumer for acceptance.These sampling plans provide for inspecting the samples fromlots or batches by attributes or variables measurement and forcontinuous sampling by attributes measurement. The three setsof matched sampling plans are indexed by seven specifiedverification levels (VL) and
45、five code letters (CL), which aredetermined by the lot or production interval size. The samplingplans are matched between corresponding VL and CL combi-nations to result in essentially similar protection. The producerhas the option to utilize the type of plan, at the sameverification level, that bes
46、t complements the production pro-cess.4.2.2 Formation and Identification of Lots or BatchesTheproduct shall be assembled into identifiable lots, sublots, orbatches, or in such other manner as may be prescribed. Each lotor batch shall, as far as practicable, consist of units of productof a single typ
47、e, grade, class, size, and composition, manufac-tured under essentially the same conditions, and at essentiallythe same time. The lots or batches shall be identified by theproducer and shall be kept intact in adequate and suitablestorage space. Although lot or batch size is not used to select aconti
48、nuous sampling plan, the formation of lots or batches mayremain desirable for reasons of homogeneity, shippingconvenience, and facilitation of payment.4.2.3 Determination of Sampling PlanA sampling plan isdetermined by:4.2.3.1 Verification level (VL) as specified,4.2.3.2 Type of sampling (attributes
49、, variables, orcontinuous),4.2.3.3 Lot or production interval size code letter (CL) fromTable 1, and4.2.3.4 Switching procedure (normal, tightened, reduced).4.2.3.5 For lot acceptance situations (attributes orvariables), the occurrence of one or more nonconformancesshall result in withholding acceptance of the product submittedand initiation of corrective action. When continuous samplingis in effect, the occurrence of a nonconforming unit while in asampling phase results in withholding acceptance of that unit,a return to screening, and initiation