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MIL-STD-1235B10 DECEMBER 1981

MILITARY STANDARD

SINGLE - AND MULTI - LEVEL

CONTINUOUS SAMPLING procedures

AND TABLE FOR INSPECTIONBY ATTRIBUTES

NO bsl,I\ERABLEDATAP.EOUIRIDBi THIS DOCUMSNT

QCIC

Downloaded from http://www.everyspec.com

?fIL-sTD-1235B“1ODecember1981

DEPAKT’MX OF DEFENSEWashington,DC 20360

SingleAnd Multi-LevelContinuousSamplinSProceduresAnd TablesForInspectionBy Attributes

!41L-STD-1235B

1. This MilitaryStandardis approvedfor use byall Departmentsand Agenciesof the Departmentof Defense.

7. . Recommendedcorrections,additionaor deletionsshouldbe addreasedto:Commander,US ArmyArmamentResearchand DevelopmentCommand,ATTN: DRDAR-TST-S,Mver, NJ 07801,

ii


10

!IIL-STD-1235B10 Dscember1981

FOREWORD

‘ThisStan..5ardprovides the tables and procedures for apDly-ing five different types of continuous seunplinqnlans forinspection by attributes:

a. CSP-1, a sinqle-level continuous sampling pro-cedure which provides for alternating between sequences of100% inspection and sampling inspection. Section 2 of thisStandard describes these plans.

b. CSP-F,. a variation of the CSP-1 plans in thatCSP-F plans are anplied to a relatively short run of pro-duct , thereby Dermittinq smaller clearance numbers to beuseti. Section 3 of this Standard describes these ulans.

CSP-2, a modification of CSP-1 in that 100%inspectioz”resumes only after a prescribed number ofdefect-free units separate any two defective sanmle units.Section 4 of this Standard describes these plans.

d. CSP-T, a multi-level continuous samDlinq pro-cedure which provides for reducina the samnlinq frequencyupon tiemonstration of superior oroduct cwallty. SectIon 5of this Standard describes tnese plans.

e. CSP-11, a sinqle-level continuous sampling pro-cedure which is an alternative to CSP-T in that these plansprovide for reducinq the clearance number in aood qualitysituations where reduction of samDlinq frequency has noeconomic merit. Section 6 of this Standard describes theseplans.

Section 7 o? this Standard contains the definitions ofterms of particular importance to the proper use of thisStandard’s provisions. Functional curves of all plans dis-cussed herein may be found in MIL-sTD-1235A-1, “FunctionalCurves of the Continuous Samplina Plans”.

iii


MIL-sTD-1235E10 December]981

SECTION 1

Paragraph 1.11.1.11.1.21.2

1.2.1

1.2.1.11,2.1.21.2.1.31.2.2

1.2.2.11.2.2.21.2.2.31.3

1.3.11.3.21.3.31.3.41.3.51.4

1.4.11.4.1.11.4.1.21.4.21.51.5.11.5.21.5.31.61.6.11.6.2

1.6.3

CONTEXTS

Paae

GENERAL DESCRIPTION OFSA.YPLI!/GPLANS. . . . . . . . . .SCOPE. . . . . . . . . . . . . .

Purpose. . . . . . . . . . . .Applicability . . . . . . . . .

CLASSIFICATION OF DEFECTS ANDD==ECTIVES . . . . . - . . . . .

Method of ClassifyingDefects. . . . . . . . . . . .Critical Defect . . . . . . .!.lajorDefect . . . . . . . .Minor Defect . . . . . . . .

Method of ClassifyingDefective . . . . . . . . . .Critical Defective . . . . .Major Defective . . . . . . .Minor Defective . . . . . . .

ACCEPTABLE QUALITY LEVEL(AC)L). . . . . . . . . . . . . .Definition . . . . . . . . . .Use. . . . . . . . . . . . . .Limitation . . . . . . . . . .Specifying AnL’s . . . . . . .Preferred AOL’S . . . . . . . .

AVERAGE OUTGOING QUALITY(AOQ) . . . . . . . . . . . . . .Definitions . . . . . . . . . .AOQ.. . . . . . . . . . . .AOQL . . . . . . . . . . . .

Limitation . . . . . . . . . .SUBMISSION OF PRODUCT . . . . . .

Lot or Batch . . . . . . . . .Order of Production . . . . . .Units of Product Submitted . .

ACCEPTANCE AND REJECTION . . . .Responsibility . . . . . . . .Special Reservation forCritical Defects . . . . . . .Disposition of RejectedProduct. . . . ... . . . . . .

11

1

1

1

1

222

2222

223333

33333334444

4

5


FIIL-STD-1235B10 December1981

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Paraqraph 1.71.7.1:..7.21.7.3:.8i.8.;1.8.2i.8.31.8.4S.9

1.9.11.9.:1.10

1.1(!.1

SF’CT-ION 2

.<. .’.. 12.2.22.2.3. .L.z.42.2.52.2.6

SEC710N 3Paragraph 3.1

3.23.2.13.2.23.2.33.2.43.2.53.2.6

SECTION 4Parar.iaph 4.1

4.24-~.l4.2.24.2.34.2.44.2.54.2.6

CONTENTS (Cent.j

Page

DRAWING OF SAMPLES . . . . .Sample. . . . . . . . . .Frequency of Sarnplina . .Sample Selection . . . . .

SIVU?LINGPLANS . . . . . . .iJefinition . . , . . . . .Code Lelters . . . . . . .Obtai]linn Samplinq Plans .Types of Sampling Plans -

DISCO?JTINI;?.TIO??OFI?!S?ZCTION . . . . . . . . .

Long Periods of ScreeninqIneffective Screening . .

ESTIPU+TION OF THE PROCESSAVLWIGE . . . . . . . . . .

Definition . . . . . . . .Computation . . . . . . .use . . . . . . . . - ..

CSP-1 . . . . . . . . . -.FEATURES OF CSP-I . . . . .DESCRIFT?DN OF PRoCEDURE . .

Initiation of rrod,Jction .Sa)fi;linglrlspectio,l . . .llcturr(Lu 10C3 Ir;spectionCi~ange in Code ietter . .Ineffective Screening . .i,onqPeriotisof Screenina

CSP-F . . . . . . . . . . .FEATUP.S5OF C.SP-F . . . . .DESCRIPTION OF PROCEDURE . .

Initiation,of Period . . .Samplinq Irispection . . .Return to 100?.InspectionChange in Code Letter . .Ineffective Screening - .Lonq Perio2s of Screenina

CSP-2 ..: . . . . . . . . .FEATURES OF CSP-2 . . . . .DESCRIPTION OF PROCEDURE . .

Initiation o= Production .Sampling Inspection . . .Return to 100% InspectionChanae in Code Letter . .Ineffective Screen5.ng . .Long Pericds of Screenino

. .

. .

. .

.,

. .

. . .

. .

. .

. .

. .

. .

. .

55.5

67733688999

iO14141414i4is15161632323232

v


HIL-sTD-1235B10 December1981

UUNTEN~S [COnt.)

1 SECTION 5Paragraph 5.1

5.25.2.15.2.25.2.35.2.45.2.55.2.6

SECTION 6Paragraph b.1

6.26.2.16.2.26.2.36.2.46.2.56.2.6

SECTION 7

FIGURE 2-A3-A4-A5-A6-A

TABLE 1

~2-A2-B3-A4-A4-B

CSP-T . .. . . . . . . . . . .FEATURE; OF CSP-T . . . . . . .DESCRIPTION OF PROCEDURE . . . .

Initiation of Production . . .Sampling Inspection . .“. . .Return to 100% Inspection . .Change in Code Letter . . . .Ineffective Screening . . . .Long Periods of Screening . .

CSP-V . . . . . . . . . . . . .FEATURES OF CSP-VDESCRIPTION OF PROC;D&& : : : :

Initiation of Production . . .Samplinq Inspection . . . . .Return to 100% Inspection . .Change in Code Letter . . . .Ineffective Screening . . . .Long Periods of Screening . .

DEFINITIONS . . . . . . . . . .

FIGURES

Procedure for CSP-1 Plans . . .Procedure for CSP-F Plans . . .Procedure for CS?-2 Plans . . .Procedure for CSP-T Plans . . .Procedure for CSP-V Plans . . :

TABLES

Sampling Frequency CodeLetters . . . . . . . . . . . .Values of i for CSP-1 Plans . .Values of S for CSP-1 Plans . .Values of i for CSP-F Plans . .Values of i for CSP-2 Plans .“.

38383838383939394044444444444545464650

1117354147

7

i:1836

Values of S for CSP-2 plans . . 37

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TABLE 5-A5-B6-A

6-B

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MIL-sTD-1235B10 December1981

CONTENTS (cont.)

Page

Values of i for CSP-T Plans . . 42Values of S for CSP-T Plans . . 43Values of i and x for CSP-VPlans . . . . . . . . . . . . . 48Values of S for CSP-V Plans . . 49

vii


XIL-STD-1235B10 December1981

GENEPAL

1.1 SCOPE

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I

SECTIOll1

DESCRIPTION OF SAMPLING PLANS

1.1.1 Purpose This Standard establishes continuoussamplinq plans and procedures for inspection by attri-butes. When this Standard is referenceti in a contract,specification, inspection standard or similar document,the provisions of this Standard shall qovern the appli-cation of all attributes type continuous sampling plansand procedures. Unless otherwise noted herein, the pro-visions of this Standard shall be carried out by thesupplier.

1.1.2 Applicability The contiitions that must existbefore th~plans nay be used are:

(a) Moving product (see 7.21).

(b) Anmle space, equipment and manpower at ornear the site o= inspection to permit ranid 100% inspec-tion wher. required.

(c) Relatively easy and auick inspection.

(d) A process which is producinu, or is capa-ble of producinq, material whose aualitv is stable(see 2.2.2(a), 3.2.2(a), 4.2.2(a), 5.2.2(a), and6.2.2(a)!.

(e) The inspection is non-destructive.

The samplina plans c?esiqnated herein are applicable,but not limlted, to inspection of various entities,viz. , end items, components, raw materials, data orrecords, and any other entities, provided that the fore-qoing conditions are satisfied.

1.2 CLASSIFICATIfI?~OF DEFECTS AND DEFECTIVES

1.2.1 ?!ethodof Classifvil,a Defects A classificationof defects IS the enumeration of possible defects of theunit of product classified according to their .SerlOusness.Defects will no~allv be orouped into one or more of thef:llowing classes; however, defects may be grouped into:tL,erclasses, or into subclasses within these classes.

1



1.2.1.1 Critical Defect A critical defect is a defectthat judqment and exper~ence indicate is likely to resultin hazardous or unsafe conditions for indil’idualsusinq,maintaining, or dependina upon the product; or a defectthat judqment and experience indicate is likely to Pre-vent perfomnance of the tactical ~,Jnctlonof a major enditem such as a shiy, aircraft, tank, missile, or soacevehicie. NOTE: For a special provision relatinq to Crcal defects, see 1.6.2.

:.2.1.2 Ma’or Defect.~< Arna]or defect isadefect otherthan critlca., t at IS llkely to result in failure ormaterially reduce the usabilitv of the unit of productfor its intended DurDose.

ti-

1.2.1.3 Minor Defect “A minor defect is a defect that isnot likelv to reduce materially the usabilitv of the unit,6? uroduct for its intended purpos~, or is a fleuarturefrom.established standards havina little bearinq on theeffective “se or Oueration Of thv unit.

l.~c~ Method of Classi?yinq Defective A defective isa unit Of product which conta~ns one or more defects.Defective will usually be cla”ssifierlas follows:

1.2.2.1. Critical De?ective A critical ~efective containsone or mo~dl-~s an? mav also contain majorand/or minor defects. NQTE : For a special nrovision re-latinq to critical defective, see 1.6.2.

1.2.2..2 Major Defective A major defective contains oneor more ma30r defects, and mav also contain minor defects,but contains no critical defects.

1.2.2.3 Minor De$ective A minor defective contains oneor more mmor defects hut contains no critical or majordefects.

1.3 ACCEPTABLE OUALITV LEVFL (AOL)

1.3.1 Definition For continuo~]s samnlina plans, theACIL is an index to the plans, and has no other meanina.

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YIL-STI)-1235B10 December1981

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I

1.3.2Letter,

f-ls~The AOL, toaether with the Sample Size Codei~sed fon indexina the plans Drovided herein.

The plans are also indexed by the Averaa@ Outqoina ?ualitYLimit (AOOL).

1.3.3 Limitation The designation of an AOL shall notimDly that the su?plier has che rioh? to supolv knowin?lyany defective unit of rmoduct.

1.3.4 Specifvinq AQL’s The AOL will be designated inthe contract or by the responsible authority. Different

AQL’s may be desianat.ed for arouns of.defects consideredcollectively, or for individual defects. An AQL for agroup of defects may be “desirrnatec?in addition to A9L’sfor individual defects, or suborou?s, within that ?rouP.

1.3.5 Preferred AQL’s The values of AOL’S aiven inthese tab?.esare known as preferred AQL’s. If, for e.n:~product, an AOL be designated othtir than a preferredADL, these tables are not applicable.

1.4 AVERAGE OUTGOING C?JALITY (AOQ)

1.4.1 Definitions

1.4.1.1 AOQ The Averaqe Outaoina “Ouality (AOQ) for anarticula~rocess averaae is the lona run expected Per-centageof defectivematerial-inthe acceptedmaterial,if theassociatedsamplingplan is followedfaithfully(see3.1 forclarifiedmeaningfor CSP-F).

1.4.1.2 AOQL The Average Outqoina Quality Limzt (AWL)IS the ma~m of all of the possible values of AOQ ifthe associated sampling plan is followed faithfully(see 3.1 for clarified meanina for CSP-F).

1.4.2 Limitation The Iistlnq of values of AOQL inthis Standard does not imply that the supplier has ai-iqhtto SUDplV knowinqly any defective unit Of ?roduct.

1.5 SUBMISSION OF PRODUCT

1.5.1 Lot or Batch Althouqh lot or batcn size isnot used to select a continuous samplinq plan, theformation of lots or batches may remain desirable forreasons of homogeneity, shippino convenience, andfacilitation of payment.

.


HL-STD-1235B10 December198i

1.5.2 Order of Production All inspection should beperformed ~n tne order In which the units of product areproduced, in order that the source of quality problemscan be more easily spotted and corrective action taken.In those situations where maintaining the order of produc-tion is not possible, for example, when product from twoor more identical production lines is merged prior toinspection, the plans herein may still be used providedthat the mixing of product from the lines is thorough,thereby assuring a random spacing of any defective unitsin the flow of product.

1.5.3 Units of Product Submitted All units for which,disposition IS sought must pass each inspection station.This does not prevent process inspection by.the supplierprior to arrival of the product at the inspection station,nor does this prohibit the supplier from removing,or cor-recting units containin~ defects prior to submittal of theproduct. However, if, In the opinion of the consumer, thesupplier~s method of scheduling process inspection resultsin a flow of product during periods of screening inspec-tion which is not representative of the flow of productwhich can be expected to be encountered durinq subsequent ●sampling inspection, the consumer reserves the right tocause the supplier to modify his method of schedulingprocess inspection.

]-fi ACC~pTANCE A!JD ~<TEcTIo}]

1.6.1 Responsibility Although both the consumer andsupplier may reject nonconforming material of the suD-plier, only the consumer possesses tne authority toaccept (purchase) the supplier’s material. However,since the supplier is responsible for providing materialwhich satisfies contractual requirements, he will in-spect the product through use of a sampling plan indexedby the designated AQL to determine whether or not to sub-mit the product to the consumer.

1.6.2 Special Reservation for Critical Defects Thesupplier may be required at the discretion of the respon-sible authority to inspect every unit for critical defectsor to follow some other procedure with regard to the in-spection of critical defects. lf a critical defect isfound OP any unit of product, even if that unit has notbeen selected for inspection for critical defects, thesupplier shall carry out the procedure specified by theconsumer for critical defects.

4


MIL-STD-1235B10 December1981

1.6.3 Disposition of Rejected Product Units found tobe defective by either the supplier or consumer shall beremoved and kept apart from the flow of product. Thesupplier may correct these units, in which case they willbe screened and resubmitted to the consumer apart from theregular flow of product. If they are accepted by the con-sumer, they will be returned to the production line rightafter the inspection station for the defects concerned.

l.? DRA\iING OF SAMPLES

1.7.1 Sample Under continuous sampling a sample con-sists of one unit of product drawn from the productionline as it passes a given station.

1.7.2 Frequency of Sampling Certain values of samp-ling frequency, f, are provided for each of the plans.

1.7.3” Sample Selection The sample units shall beselected at the chosen sampling frequency (f) so as togive each unit of product an equal chance of being in-

0

spected. The inspector should allow the interval be-tween sample units to vary somewhat rather than drawsample units according to a riqid pattern.

1.8 sA.f4PLrNGPLANS

1.8.1 Definition As used herein, the phrase “samp-ling plann denotes a particular procedure and the size(s)of the clearance number(s) and sampling frequency(ies)associated with it.

1.8.2 Code Letters Sampling plans are designated bycode letters. Table 1 provides permissible code lettersbased on the number of units in the production interval.A code letter and its associated sampling frequencyshould be selected after considering such influencingfactors as inspection time per unit of product, produc-tion rate, and proximity to other inspection stations.when idle inspector time is a“significant consideration,a Plan with a higher sampling frequency and lower clear-ance number is usually preferred.

1.8.3 Obtaininq Sampling Plans The AQL and an appro-priate code letter shall be used to obtain the samplingplan from Table 2-A, 3-A, 4-A, 5-A, or 6-A. For CSP-F,it is also necessary to determine N (see 3.2.1).

5



1.8.4 Types ~f Sampling Plans Five types of samplingplans: csP-1, CSP-F, CSP-2, CSP-T, and CSP-V are pro-,.~idedin Tables 2-A, 3-A, 4-k, 5-A, and 6-A respectively.A selection of the appropriate plan can be made by a con-sideration of their individual features. CSP-1 is thesimplest. CSP-F is a CSP-1 plan with clearance numberadjusted to handle a shorter run of product. CSP-2 pro-vides advance warning when a screening crew may have tobe assembled. CSP-T provides for a reduction in samplingfrequency in good quality situations. CSP-V provides fora reduction in clearance number in good quality situations,and is an alternative to CSP-T in those situations where areduction in sampling frequency has no economic merit.

1.9 DISCOWTINUATION OF INSPECTION

1.9.1 Long Periods of Screening hfienthe use of 2,2.6,3.2.6, 4.2.6, 5.2.6, and 6.2.6 give indication that anexcessively long period of screening has been in progress,corrective action shall be taken to improve the productionprocess and the consumer reserves the right to suspendproduct acceptance. The provisions of 2.2.6, 3.2.6, 4.2.6,5.2.6, and 6.2.6 do not prevent the supplier from takinqcorrective action to improve the production process prior ●:0 reachi~g the limits described in the aforementionedparagraphs.

I.cj.z Ineffective Screeninq If, during a period of 100?inspection, a checking ].nspectorfinds a defect, the con-sumer shall be notified, and corrective action shall betaken to improve the effectiveness of the screening crew.If a second defect is found by the checking inspectorduring this period of 100% inspection, the same actionshall be taken by the supplier, and the consumer will re-serve the right to suspend product acceptance. In thecase of critical defects, the consumer reserves the riuhtto suspend acceptance upon the finding of thecal defect by the checking inspector during a1008 inspection,

1.10 ESTIMATION OF THE PROCESS AVERAGE

1.10.1 Definition The process averaqe (PA)as the percent defective of product submitted

first crlti-period of

is definedby the sup-

plier for original inspection. Original inspection is thefirst inspection of a particular quantity of product as

6


?lIL-ST~1235B10 December1981

10

I

distinguished from the inspection of product which hasbeen previously submitted. The phrases “ProcessAverage” and “Percent Defective of Submitted Product”

-are used interchangeably.

1.10.2 Computation ?.reasonably good estimate of theprocess average can be made from the inspection results.If the inspection results used are for a set period oftime or a pre-set number of units, the process averagecan be estimated as follows:

PA 100 (number of defective observed)est = number of units Inspected

1.10.3 Use The estimate of the process average, besidesgiving an=dicakion of what percentage of manufacturedproduct is defective, can also be used to consult thecurves give,n in NIL-sTD-1235A-1.

TABLE 1

SAMPLIliG7REOUl?NCY’CODE LETTERS

Number of Units i]] PermissibleProduction Interval Code Letters

2-8 A,n9-25 A through C

26-90 ‘A through D

91-500 A through E501-1200 A through F’

1201-3200 A through G

3201-10,000 A through H10,001-35,000 A through I35,001-150,000 A through J

lso,ool-up A through K

7

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SECTION 2

CSP-I

2.1 FEATURES OF CSP-1

CSP-1 is a single-level continuous sampling pro-cedure which provides for alternating sequences of 100%inspection and samplinq inspection with no limit as tothe number of such sequences. CSP-1 requires a returnto 100% inspection whenever a nonconforming unit is dis-covered during semplinq inspection. See Figure 2-A fora summary of the operation of CSP-1. Tables 2-A and 2-Blist parameters associated with the procedure.

2.,2 DESCRIPTION OF PROCEDURE

2.2.1 Initiation of Production At the start of pro-duction, each unit of product shall be inspected by thescreening crew. Checking inspection shall be performedconcurrently at a frequency f or nore often on the unitspassed by the screening crew (see 2.2.5).

2,2.2 Sampling ?nspection ~~.m.p~~~g~~~na-+im. ~~~-:-------really is ~nlt~ated when the following requ~rements aresatisfied:

(a) All units of DrOduct are nacleaccordinq tothe same drawinq and specifications under stable condi-tions of production, This requirement, which is termedhomogeneity, is usually satisfied when the productionprocess !.snot-altered by innovation, significant changesin materials, strikes, retoolinq (other than that due toroutine changes to compensate ‘or tool wear) or interrup-tions other than those due to the end of the shift, day,or week.

(b) At least i consecutive units inspected bythe screening crew durinu 100?,inspection are found freeof the defects concerne~-

(C) None of the i consecutive units founddefect-free by the screening crew are found defectiveby the checking inspector(s). t7hensanplinq inspectionis begun, screeninq is terminated and samples are takenat the frequency, f.


?!IL-STD-134jB10 December1981

inspection2.2.3 Return to 100% Inspection Samplingshall be termnated and 100% Inspection shall be re-sumed if either or both of the c~nditions describedbelow occur. For critical defects, szrzeninq shall“beginwith t’neunit of product just after the lastdefect-free sample unit. (See 1.6.2 for further pro-visions for critical defects. )

(a) The production process is interrupted. formore than three operating days, or the requirement of2.2.2(a) is otherwise not satisfied.

(b) A unit having any of the defects con-cerned is found by the sampling ins?ector.

When 100% inspection is required, the flow of product “iscurtailed until the screening crew can begin 100% inspec-tion. 100! inspection shall be continued until therequirements of 2.2.2 are met.

2.2.4. Chanqe in Code Letter If it is necessary ordesirable to change Sampling Frequency Code Letters, thefollowinq applies:

(a) If the change results in an increase inthe sampling frequency, f (and, of course, a decreasein the clearance number, i), the chanqe maY be made .atthe next shift from a screening sequence to a s~Plin9sequence or during a sampling sequence, whichever isthe earlier.

(b) If the change results in a decrease inthe sampling frequency, f (and, of course, an increasein the clearance number, i), the change may be made atthe next shift from a sampling sequence to a screeningsequence or during a screening sequence, whichever isthe earlier. (At any time the change may be made byinitiating a screeninq sequence whose clearance number,i, will be that associated with the new code letter. )

2.2.5 Ineffective Screeninq Whenever the checkinginspector lnsa~e product found conformingby ~he screening crew, the Screening crew shall start anew count of consecutive defect-free units, and theactions described in 1.9.2 shall be carried out.

9



2.2.6 Long Periods of Screening If, during a periodof 100% insDectlon, a defect IS found before findina iconsecutive conforming units and the numberof unitsscreened is equal to or greater than the appropriate valueof S in Table 2-B, the supplier shall notify the consumerof this occurrence, and corrective action shall be takento improve the production process. The consumer may, atits option, suspend acceptance immediately or at any timethereafter during the period of 100% inspection until thesupplier corrects the cause(s) of the high rate of defec-tiveness. After effective corrective action has beentaken, 100% inspection shall be reinitiated.

1“

10


NIJ.-STD-li’35310 December19SI

I

STARTJ

4 The screening crew inspects 100% of the units.

I l%nen i consecutive units are fount?free of thedefects conccrncd,

1

I

The scree!lir]ycrew is reieased from 1003 inspec-tion and the sampling inspector inspects a frac-tion, f, or the units, where” the sample unitsare selected in random manner.

When the sampling inspector finds one of thedefects concerned,

I

FIGURE 2-A. PROCEDURE FOR CSP-1 PLANS

11


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.— Sam

pFrvq

code

Ltr

——-

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112

113

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115

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1/15

1/25

1/50

1/100

1/200

—--.—

TA

IJI.

EZ

-A

Val

ues

ofirorCSI>-lPl:lns

——

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L541J840

bOO

375

265

194

2550

1390

1000

620

405

321

334Lr1820

1310

810

530

4“20

396(321@3

1550

965

630

498

4950

2700

i940

1205

6050

3300

2370

1470

7390

403U

2890

1800

911U

4970

3570

2215

117306400

4590

2855

790

623

965

762

I80

930

450

1147

870

1477

14320

7810

5600

3485

2305

18?0

174209500

6810

4235

2760

2178

],/,0FJ4

232

140

303

182

360

217

450

270

550

335

672

410

828

500

1067

6L0

[302

790

1583

950

—-.

.—.

——

.—

53

87

113

135

168

207

255

315

400

500

590

——

36

23

59

38

76

49

91

58

113

73

138

89

170

108

?10

134

270

175

330

215

400

255

1.3

..3J+

.U

0.>

lU.

U—

—.—

..—.

-—.

_.

15

25

32

38

47

57

70

86

110

135

1.65

10

16

21

25

31

38

46 57

72

89

106

6 10

13

15

18

22

27

33

42

52

62

——

53

75

96

11

7

13

8

16

10

19

1.2

23

14

29

18

36

22

43

26

.018

.033

.0~6

.074

.113

.143

.1.980.33

0.53

0.791.221.902.904.947.1211.46

-—..

AO

(JL

inX

_..

—.-

——

.—

.——

—

*AI)

L’s

arc

pro

vid

ed:)

sindicestosimpllfyuscofthiscal)le, bu

th

ave

no

oth

erm

ean

ing

rela

tive

tutl

Iep

lan

s.


TilB1/E2-B

1-,L

.1

I

,’

Sam

pF

req

Co

de

Ltr A B c D E F G H I J K—

f L/2

1/3

1/.4

1/5

L17

1/10

1/15

1/25

1/50

1/100

1/200

Val

ues

ofSfor

CS

P-1

Pla

ns

.——

_.

AQ

1.*in%

-—

.010

.0L5

.025

.040

—-

......—

.065

0.10

0.15

0.25

0.40

0.65

1..01.5

2.5

4.0

6.5

113.O

——.--——

1850

925

721

451

295

4080

1950

1600

993

6L9

6010

2915

2360

1460

1010

B320

3890

3100

1930

1390

11400

5670

4660.28951980

16900

7590

6640

4120

2800

2440011300

9250

5760

4020

355001690013900

8640

5950

5980026900230001430010300

960003980036LO023300,16900

148100637005BOO03600029000

273

L97

119

75

579

442

268

166

926

69!I

421

262

1150

97!i

589

367

1750

1355

813

507

2595

1985

1245

624

3820

2960

1810

922

57L0

4560

2760

1390

10100

8440

5070

3170

16500143008710

6020

2850025400152009470

55

36

22

17

120

78

52

36

L77

11.5

79

57

258

165

109

76

376

244

1S4

109

5L3

352

221

164

856

524

327

241

L350

839

524

390

24451590

913

733

3980260016401.360

8030436528352150

11

1.0

‘2(,19

36

2B

45

40

63

54

90

82

141

138

212

189

368

334

6f+2601

10801025

6 16

20

27

34

51 75

05

ZI.2

. 352

636

.018

.033

.046

.074

.113

.143

.19.30.33

0.53

0.791.221.902.9I34.947.1211.66

.._—

——

AOQLin%

——

*AQ

L’s

are

pro

vid

edas

indicestosimplifyuseofthistable,buthavenoother

mea

nin

g

rela

tive

toth

ep

l,an

s.


3.2.1 Initiation of Period The period, in terms nfnumber of units, N, for wh~ch the plan is to he apr,lied,must first be determined, and plan parameters determinedfrom Table 3-A. (If N is smaller than th,-’val!]eof’i fromTable 3-A, inspect all units.) At the start of productionor of the period for which the plan is to be applied, eachunit of product shall be inspected by the screening crew.Checking inspection shall be performed concurrently at afrequency f or more often on the units passed by thescreening crew (see 3.2.5).

3.2.2 Sampling Inspection Sampling inspection normallyis initiated when the following requirements are satisfied:

(a) All units of product are made accordinq tothe same drawings and specifications under stable condi-tions of production. This requirement, which is termedhomogeneity, is usually satisfied when the productionprocess is not altered by innovation, significant changesin materials, strikes, retooling (other than that due toroutine changes to compensate for tool wear) or inter-ruptions other than those due to the end of the shift,day, or week.

14

XTL-STD-1235B10 December1981

SECTION 3

CSP-F

‘3.1 FEATURES OF CSP-F

CSP-F is a single-level continuous sampling pro-cedure which provides for alternating sequences of 100%inspection md sampling inspection. CSP-F is equivalentto the application of a CSP-1 plan to a specified numberof units at a time, thereby permitting a smaller clear-ance number to be used. The pl~n may be apalied i? situ-ations involvinq short production runs, or lt may beapplled to one or more production intervals at a time insituations involvinq time consuming inspection operations(for example, inspection with X-rzy equipment) where alarger clearance number could cause a orod’uctionbottlen-eck. See Figure 3-A for a summary of the operations ofCS?-F. Table 3-A lists parameters associated with the

AOQ and AOQL for CSP-F relate to the long run

‘m:?:i::v:::of :

, wl)ich in fact I“rethe sams as therespectively, for a sinqle aonlication of


MIL-STD-1235B

10 December19s1

‘o(b) At least i consecutive units inspected by

the screening crew during 100% inspection are found freeof the defects concerned.

(c) None of the i consecutive units founddefect-free by the screening crew are found defectiveby the checking inspector(s). When sampling inspectionis begun, screening is terminated and samples are takenat the frequency, f.

3.2.3 Return to 100% Inspection Sampling inspectionshall be ternunated and 10O% inspection shall be resumedif my of the Conditions described below occur. Forcritical defects, screening shall begin with the unitof product just after the last defect-free sample unit.(See 1.6.2 for further,provisions for critical defects. )

(a) The production process is interrupted formore than three operating days,.or the requirement of3.2.2(a) is otherwise not satisfied.

(b) A unit having any of the detects concernedis found by the sampling inspector.

(c) The units to which the’pian was int=nfi~?to be ap?lied have reached the point of inspection.

The remaining units to be produced will be broken downinto one or more groups, and the i value, for each groupwill be determined from Table 3-A. For example, supposethat initially the size of a production run is to be3,000 units, and subsequently it is determined that therun is to be 4,000 units. After 3,000 units have passedthe ‘?ointof inspection, 100% inspection will be initi-ate?, with an i value associated with N = 1,000.

When 100% inspection is required, the flow of product iscurtailed until the screening crew can begin 100% inspec-tion. 100% inspection shall be continued until the re-quirements of 3.2.2 are met.

3.2.4 Change in Code Letter If it is necessary ordesirable to change Sampling Frequency Code Letters, thefollowing applies:

15



(a) If the change results in an increase inthe sampling frequency, f (and, of course, a decreasein the clearance number, i) , the change may be made atthe next shift from a screening sequence to a sempiingsequence or “during a sampling sequence, whichever isthe earlier.

(b) If the change results in a decrease inthe sampling frequency, f (and, of course, an increasein the clearance number, i), the change may be made atthe next shift from a sampling sequence to a screeninqsequence or during a screening sequence, whichever isthe earlier. (At any time.the change may be made byinitiating a screening sequence whose clearance number,i, will be that associated with the new code letter. )

3.2.5 Ineffective Screening Whenever the checkinginspector fuds a defect in the product found conform-ing by the screening crew, the screening crew shallstart anew count of consecutive defect-free units,and the actions described in 1.9.2 shall be carriedout.

77C. LCrLcj Periods of scre~i,ir,q..... if, duii.JIqd periodof 100% inspect~on, a defect IS found before findinq iconsecutive conforming units and the numberofunits screened is equal to or greater than the appro-priate value of S in Table 2-B (before N units havereached the point of inspection) , the supplier shallnotify the consumer of this occurrence, anticorrectiveaction shall be taken to improve the production process.The consumer may, at its option, suspend acceptanceimmediately or at any time thereafter tiuring the periodof 100% inspection until the supplier corrects thecause(s) of the high rate of defectiveness. Aftereffective corrective action has been taken, 100% in-spection shall be reinitiated. (Note: If several con-secutive periods of some length N each have passed wit5-out going to sampling, and without reaching the S valuebecause N is smaller than S, the consumer reserves theright to cause the supplier to use another samplingplan. )

16


STAQ?—m

* The screening crew inspects 100% of the units. I

I When i consecutive units are found free of thedefects coq~erned, I

IThe screening crew is released from 100% inspec-tion and the sampling inspector inspects a frac-tion, f, of the units, where the sample unitsare selected in a random manner. I

I When the sampling inspector finds one of thedefects concerned,. !

II

~oT~ : This plan is applied to a specifiednumber of units, N, to be produced in thepsriod considered.

FIGURE 3-A. PROCEDURE FOR CSP-F’PLANS

‘o17

.


I

AQL*

-.010%

AOQL

-.018%

Samp

Freq

Code

Ltr

f .,

1-500

501-600

601-700

701-800

001-1,000

1,001-1,500

1,501-2,000

2,001-3,000

3,001-4,000

4,001-5,000

5,001-6,000

6,001-7,000

7,001-8,000

8,001-9,000

9,001-10,000

10,001-11,000

11,001-12,000

12,001-15,000

15,001-20,000

20,001-30,000

‘1’AllLE3-A-1

Val

ues

ofi

forCSP-F

Plans

An

cD

1/2

1/3

1/4

1/5

1?7~

347

376

387

392

398

400

402

432

405

407

449

458

461

164

441

485

470

472

502

517

519

482

523

530

529

533

577

585

589

545

591

594

618

596

647

662

678

689

697

703

679

784

929

1029

1101

1156

1199

1234

1262

1286

799

942

1163

1328

1458

1564

1651

1725

1789

1844

843

1008

126,4

1462

1624

1759

1874

1974

2061

2138

870

1044

1320

1538

1718

1871

2004

2125

2224

2317

900

1082

1380

1620

1822

1996

2149

2285

2408

2520

903

1108

1423

1679

1896

2086

2255

2407

2545

2671

920

1128

1455

1723

1952

2154

2335

2499

2649

2788

935

1143

1479

1757

1996

2208

2398

2572

2732

2880

1306

1091

2207

2400

2622

2788

1323

2917

1933

3018

2269

2496

2716

2897

3037

3148

1363

.2034

2420

2666

2957

3181

1405

3356

3497

2146

2598

2898

3265

3554

1449

3787

2271

3975

2808

3183

3670

4076

4414

4698

—


Samp

Freq

Code

Ltr

f N

30,001-40,000

40,001-50,000

50,001-60,000

60,001-70,000

70,001-80,000

80,001-90,000

90,001-100,000

100,001-150,000

150,001-200,000

200,001-250,000

250,001”-300,000

300,001

and

over

AB

cF

_..—

1/2

1/3

------m

&..

“1?7

1/10

—..

.—.

-—.

G1/15

H1/25

1473

2340

2926

2352

3924

4424

1487

2383

3003

3462

4097

4674

1497

2413

3056

3539

4223

4861

1504

2435

3095

3597

4317

5005

1509

2451

3125

3642

4391

5120

1514

2464

3149

3677

4451

52”13

1517

2475

3168

3706

4500

5291

1527

2507

3228

3796

4652

5539

1532

2523

3258

3842

4733

5673

1535

2533

3277

3870

4783

5756

1537

2540

3290

3890

4816

5813

1540

2550

3340

3960

4’950

6050

—..—

..-—

..

..

.—

4858

5191

5451

5659

S828

5969

6088

6481

6700

6840

6936

7390

...

...

.

*AQL~S

are

provided

as

indices

to

simplify

us<

of

this

table,

but

have

no

other

meaning

relative

to

the

plans.

5232

5651

5990

6271

6508

6712

6888

7501

7865

8105

8274

9110


&!

AQL*

-.015:

AOQL

-.033%

Samp

Freq

Code

Ltr

f N

1-500

501-700

701-1,000

1,001-2,000

2,001-3,000

3,001-4,000

4,001-5,000

5,001-6,000

6,001-7,000

7,001-8,000

8,001-9,000

9,001-10,000

10,001-11,000

11,001-12,000

12,001-15,000

15,001-20,000

20,001-30,000

30,001-40,000

40,001-50,000

50,001-60,000

———

—..

.._.

TA

RL

E3-A-2

Values

oi

iforCSP-F

Pla

ns

1?2

___

-~

1;3

–-+j&—_.lD

EF

——

_o.-+-+T

282

340

411

545

617

661

691

713

729

742

752

760

767

773

786

800

815

822

826

829

.-——

..—

318

332

400

421

490

522

697

764

826

924

cJl~

1041

981

1132

1032

1204

1072

1263

1104

1321

1131

1354

1153

1389

1172

1420

1189

1447

1229

1509

1266

1570

1309

1654

1332

1695

1345

1720

1355

1737

—.

..——-...——....

340

347

437

442

540

559

802

843

981

1043

1115

1198

1222

1324

1309

1431

1382

1521

1442

1600

1498

1669

1544

1731

1584

1786

1620

1835

1706

1958

1803

2101

1911

2272

1971

2370

2009

2433

2035

2477

353

357

455

460

572

581

872

894

1.088,

1122

1259

1305

1400

1458

1521

1591

1626

1708

1719

1813

1802

1907

1877

1994

1945

2073

2007

2145

2163

2334

2358

257t3

2604

2907

2753

3120

2852

3268

2922

3377

359

465

589

911

114C

1341

1504

1647

1773

1888

1992

2088

2176

2259

2476

2765

3179

3466

3678

3841


60,001-70,:100

831

1362

1750

2,]54

2509

2974

3460

3970

70,001-80,000

833

i367

1759

2068

2534

.3015

3525

4075

80,001-90,000

934

1371

1767

2380

2554

3048

3578

4161

90,001-100,000

I~

jj‘L374

1773

2389

2570

3074

3621

4234

100,001-150,OOO

1338

i’J8fl

1792

2117

2619

3157

3759

4471

I150,00i

and

uvcr

I840

1390

1820

2160

2700

3300

4030

4970

●AOL’s

are

provided

as

indices

to

simplify

~Jseof

this

table,

but

have

no

other

mmeaninq

relative

to

the

plans.

,-


AQL*

-.025%

AOQL

-.0460

Samp

Freq

Code

Ltr

f N

1-500

501-700

701-1,000

1,001-2,000

2,001-3,000

3,001-4,000

4,001-5,000

5,001-6,000

6,001-7,000

7,001-8,000

8,001-9,000

9,001-10,000

10,001-11,000

11,001-12,000

12,001-15,000

15,001-20,000

20,001-30,000

30,001-40,000

40,001-50,000

50,001-60,000

TA

Bl,E

3-A-3

Val

ues

of

ifo:cCSP-F

Plans

AB

cD

EF

GH

1/2

1/3

1/4

1/5

1/7

1/10

51/25

245

284

299

307

316

293

322

326

351

329

377

385

400

407

342

417

42o

420

454

472

492

506

434

516

576

524

642

680

721

751

479

774

666

791

760

816

877

923

957

985

506

726

843”

914

996

1056

523

1103

768

1140

905

990

1090

1165

535

800

1223

1270

953

1.051

1167

1256

544

1326

824

1382

991

1.100

1232

1334

551

1416

1482

843

1022

1.141

1287

1402

1495

1571

557

859

1047

1.175

1334

561

871

1462

.1566

1651

1069

1,204

1376

1515

1630

1725

565

882

1089

1.230

1412

1563

568

1688

892

1103

1792

1251

1444

1606

576

1741

912”

1854

1139

1303

1522

1712

1876

2016

583

935

‘1178

1.359

1610

1838

591

958

2044

2227

1220

1420

1710

1990

594

2260

2518

970

1242

1453

1765

2077

597

2392

2709

977

1255

1473

1800

2133

598

982

2480

2846

1265

,1487

1824

2172

2544

2947

●


●

Samp

Freq

Code

Ltr

Ac

DF

f1/2

173

l??

1/4

1/5

1/10

1;15

.1725

N

60,001-70,000

599

985

1271

1497

1841

2201

2591

3025

70,001-80,000

600

988

1276

1505

1855

2224

2628

3088

80,001-90,000

600

990

1280

1511

1865

2241

2657

3138

90,001-100,000

600

994

1283

1516

1874

2256

2681

3180

100,001

and

over

600

1000

1310

1550

1940

2370

2890

3570

●AQLS9

are

provided

as

indices

to

simplify

use

of

this

table,

but

have

no

Other

meaning

relative

to

the

plans.


fiQL*-

.040%

AOQL

-.074%

SdMp

Fr,?q

Code

Ltr

—f

.—

N—

.—

L-500

501-1,000

1,001-2,000

2,001-3,000

3,001-4,000

4,001-5,000

‘\,001-6,000

J,001-7,00(?

7,00;.-J3,LJO!I

n,oiJ1-9,rJJo

!2,001-10,000

10,001-11,000

11,001-i2,000

12,001-15,000

15,001-20,000

20,001-30,000

30,001-40,000

40,001-50,000

50,001-60,000

60,001-70,000

70,001.and

over

.—-...

..—.

...

TAJ3LE3-A-4

Values

of

iEorCSP-F

Flans

-+—

.+.+

ID

FG

H1;7

1/10

1/15

/25

—.— 195

233

250

259

268

275

280

253

284

327

361

380

400

415

426

435

302

424

485

522

563

59J

617

324

474

635

557

602

668

713

74a

336

504

776

604

667

744

803

850

887

343

525

636

710

801

874

932

348

539

979

660

743

847

931

352

1000

1057

550

679

769

884

979

355

1058

1124

559

693

789

914

1020

357

566

L109

1184

705

ao~

939

1054

1153

1237

359

571

715

819

960

1084

1192

361

1285

576

123

831

979

1111

362

1227

1329

580

730

841

995

1134

365

1258

1369

588

746

864

1032

1189

368

1335

1469

598

762

888

1072

1251

1426

1595

371

607

779

914

1116

1321

373

1534

1756

612

788

928

1139

1359

373

1595

1855

615

794

936

1153

1383

374

1635

1921

617

797

942

1163

1399

1662

375

1968

618

800

946

1170

1411

1682

2004

375

__6?o.._–

._?!.”...

96:..

1205

1470

1800

2215

..._._—

—.

●AQL’s

are

provided

as

indices

to

simplify

use

of

this

table,

buc

have

no

other

meaning

r{~lativc.to

the

plans.

●●

�


●●

AQL*

-.0650

AOQL

-.113%

Samp

Freq

Code

Ltr

f N

1-500

501-1,000

1,001-2,000

2,001-3,000

3,001-4,000

4,001-5,000

5,001-6,000

6,001-7,000

7,001-8,000

8,001-9,000

9,001-10,000

10,001-11,000

11,001-12,000

12,001-15,000

15,001-20,000

20,001-30,000

30,001-40,000

40,001

end

over

TABLE

3-A-5

Values

of

iforCSP-F

Plans

AB

cD

EF

GH

1/2

1/3

1/4

1/5

1/7

1/10

1/15

1/25

155

190

207

216

226

233

239

187

254

286

305

325

340

352

‘213’

312

367

401

441

471

494

223

339

409

455

510

554

589

229

354

434

489

558

614

659

232

364

451

512

592

659

715

235

371

463

529

618

694

760

236

376

472

542

638

722

797

238

380

479

552

654

746

828

239

384

485

560

667

765

855

240

386

489

567

678

782

879

240

388

493

573

687

796

899

241

390

496

578

695

808

917

242

394

504

588

713

836

959

243

398

511

600

732

867

1007

245

402

519

611

752

900

1061

245

404

523

617.

762

918

1090

245

405

530

630

790

965

1180

.*AQL’sare

provided

as

indices

to

simplify

use

of

this

table,

but

have

no

other

meaning

reiative

to

the

plans.

243

361

513

617

697

762

816

862

902

937

968

995

1020

1082

1154

1242

1292

1450


IAQL*

-0.10%

AOQL

-.143?,

Samp

Freq

Code

Ltr

f N

NJ m

1-500

501-1,000

1,001-2,000

2,001-3,000

3,001-4,000

4,001-5,000

5,001-6,000

6,001-7,000

7,001-8,000

8,001-9,000

9,001-10,000

10,001-11,000

11,001-12,000

12,001-15,000,

15,001-20,000

20,001-30,000

30,001-40,000

40,001

and

over

TABLE

3-A-6

Values

of

ifor

CSP-F

Pla

ns

AB

1/2

.-_&

--_.

+..._

.E

1/3

_–—.–.--.–

_-:–__.z?.:

:

130

167

184

193

204

156

217

248

267

287

173

260

310

342

377

180

278

340

382

434

184

288

357

406

469

186

295

369

422

494

188

300

377

434

512

189

303

383

442

526

190

305

387

449

537

190

307

391

454

545

191

309

394

459’

553

191

310

396

462

559

192

312

398

465

564

192

314

403

472

576

193

317

408

480

588

194

319

413

,487

601

194

321

415

491

608

194

321

417

493

612

—_..—____

F“1-71O”

...—.

211

302

410

477

522

556

582

603

619

633

644

654

662

681

701

723

734

741

--..—.

G-1-/15

216

314

433

511

567

611

645

673

696

716

733

747

760

790

822

858

077

889

1}25

221

323

452

539

605

657

700

737

768

794

818

839

857

902

954

1014

1048

1069

...-—

●AQL’s

are

provided

as

indices

to

simplify

use

of

this

table,

but

have

no

other

meaning

relative

to

tllc,plans.


TABLE

3-A-7

Values

of

iforCSP-F

Plans

AQL*

-0.15%

AOQL

-.198%

Samp

Freq

Code

Ltr

- 1-500

501-1,000

1,001-2,000

2,001-3,000

3,001-4,000

4,001-5,000

5,001-6,000

6,001-7,000

7,001-8,000

8,001-9,000

9,001-10,000

10,001-11,000

11,001-12,000

12,001-15,000

15,001-20,000

20,001-30,000

30,001

and

over

AB

cD

EF

G1!

1/2

1/3

/4

1/5

1/7

1/10

1/15

1/25

103

119

130

133

135

136

137

138

138

139

i39

139

139

140

140

140

140

138

173

199

209

215

155

201

242

260

270

164

219

271

295

310

174

23’3

306

342

364

182

254

335

382

413

187

266

358

415

455

192

275

377

443

492

530

561

586

607

625

434

451

463

473

481

485

508

526

541

553

219

221

223

224

226

276

281

284

287

289

319

326

331

334

337

379

390

398

404

409

226

227

228

229

230

290

291

293

295

298

340

342

343

347

351

413

417

420

426

433

487

493

498

508

520

563

572

579

597

615

640

654

666

694

725

760

828

232

232

300

303

355

360

440

450

531

550

635

672

●AQL’S

are

provided

as

indices

to

simplify

use

of

this

table,

but

have

no

other

meaning

relative

to

the

plans.


TABLE

3-A-8

Values

of

ifor

CSP-F

Plans

AQL*

-0.25%

AOQL

-0.338

Samp

Freq

Code

Ltr

AB

cD

EF

GH

ff

1/2

1/>

1/d

1/5

1/7

Ifln

1/1<

1/9

K-,

--,

--r

.-r

--,

.-,

---,

L-

ii

A,-

-

1-500

70

99

114

123

133

140

146

501-1,000

151

77

116

140

155

174

188

200

209

1,001-2,000

81

127

158

181

211

236

258

277

2,001-3,000

82

132

166

192

228

3,001-4,000

261

83

291

134

318

170

198

237

276

312

34’

4,001-5,000

83

135

173

.201

244

286

327

“..)6

5,001-6,000

84

136

174

204

248

293

338

6,001-7,000

84

137

384

176

206

251

298

346

397

7,001-8,000

84

137

177

207

254

302

353

408

B,001-9,000

84

138

177

209

256

305

358

416

9,001-10,000

94

138

178

209

257

308

362

424

10,001-11,000

84

138

178

210

239

310

366

430

11,001-12,000

84

139

179

211

260

312

369

435

12,001-15,000

139

180

212

262

H316

376

447

15,001-20,000

140

181

214

265

320

384

460

20,001

and

over

84

140

182

217

270

335

410

500

●AQL’s

are

provided

as

indices

to

simplify

use

of

this

table,

but

have

no

other

meaning

relative

to

the

plans.


TABLE

3-A-9

Values

of

ifor

CSP-F

Plans

AQL*

-0.40%

AOQL

-0.53%

Samp

Freq

Code

Ltr

f

1-500

501-1,000

1,001-2,000

2,001-3,000

3,001-4,000

4,001-5,000

5,001-6,000

6,001-7,000

7,001-8,000

8,001-9,000

9,001-10,000

10,001-11,000

11,001-15,000

15,001

and

over

A“

Bc

DE

FG

1/2

1/3

/~

1/5

/7

1/10

715

+& —.—

47

69

82

91

100

108

113

118

50

78

96

108

125

138

149

159

52

83

104

121

144

165

185

203

52

84

108

125

151

111

202

227

53

85

109

128

156

184

213

243

53

86

110

129

158

188

220

254

53

86

111

130

160

191

225

262

53

86

111

131

162

194

229

269

53

87

112

132

163

195

231

273

53

87

112

132

163

197

234

277

53

87

112

133

164

198

236

281

53

87

113

133

165

199

237

283

53

B7

113

134

166

201

241

291

53

87

113

135

168

207

255

315

*AQL’s

are

provided

as

indices

to

simplify

use

of

this

table,

but

have

no

other

meaning

relative

to

the

plans.


TA

BL

,E3-

A-1

O

Val

ues

of

ifo

rC

SP

-FPlans

AQL*

-0.65%

hOQL

-0.79$

SarrmFrea

Cod;

Ltr’

c ..

1-500

501-1,000

1,001-2,000

2,001-3,000

3,001-4,000

4,001-5,000

5,00i-10,000

10,001

and

over

Gz g~ no+

~’i’

AB

cD

EF

GH

:K

1/2

1/3

-~

1/4

1/5

1/7

1/10

1/15

1/

-m

m

33

35

35

36

36

36

36

36

50

5457

5858

58

59

59

61

68

68

78

72

84

74

87

75

88

75

88

76

90

76

91

77

84

92

104

102

120

106

125

108

128

109

131

112

135

113

138

90

114

136

145

151

154

162

170

95

123

152

167

176

182

195

210

%’

w“

0AOL*

-1.0%

TABLE

3-A-11

A~QL

-1.22%

1-500

22

35

43

49

56

501-1,000

63

68

73

23

37

46

54

64

74

1,001-2,000

23

38

83

92

48

56

69

81

95

2,001-3,000

23

38

109

49

57

70

84

99

3,001-4,000

23

“38

117

49

58

71”

86

102

121

4,001-5,000

23

38

49

58

72

87

5,001-10,000

23

38

104

124

49

58

73

89

107

10,001

and

over

23

38

130

49

58

73

89

108

134

●AQL’s

are

provided

as

indices

to

simplify

use

of

this

tab

le,

but

have

no

Other

meening

relative

to

the

plans.


AQL*

-1.5%

AOQL

-1.90%

Sdmp

Fre

qCode

Ltr

~u

1-500

501-1,000

1,001-2,000

2,001-3,000

3,001-4,000

4,001-5,000

5,001-6,000

6,001-7,000

7,001-8,000

8,001-9,000

9,001-10,000

10,001

and

over

TABLE

3-A-12

Values

of

ifor

CSP-F

Plans

~--

+-

“..7

%!

c.,1/15-:’

15

23

15

24

15

25

15

25

15

25

15

25

15

25

15

25

15

25

15

25

293132

32

32

32

3232

3232

3436

37

38

38

38

38‘

38

3838

4043

46

46

47

47 47 47 47 47

4551

54

56

56

57

57

575757

5059

64

66

67

68

69

696969

15

25

32

38

47

57

70

15

25

32

38

4.7

57

70

_——

..

.

●AQL’s

are

provided

as

indices

to

simplify

use

of

this

table,

but

have

no

other

meaning

relative

to

the

plans.

I-72‘

55

6675

79

81

82

83

848485

85

85



SECTION 4

CSP-2

4.1 FEATURES OF CSP-2

CSP-2 is a type of single-level continuous sam-pling procedure which provides for alternating sequencesof 100% inspection and sampling inspection with no limitsas to the number of such sequences. CSP-2 requires areturn to 100% inspection whenever two defective unitsare found separated by fewer than i consecutive eanpledunits but does not require return to 100% inspection ifi or more consecutive defect-free sample units separatetwo defective units. CSP-2 shall not be used for inspec-tion for critical defects (see also 1.6.2). See Figure4-A for a summary of the operation of CSP-,2. Tables 4-Aand 4-B list parameters associated with the procedure.

4.2 DESCRIPTION OF PROCEDURE

4.2.1 Initiation of Production At the start of pro-duction, each unit of product shall be inspected by thescreening crew. Checking inspection shall be performedconcurrently at a frequency f or more often on the units ●passed by the screening crew (see 4.2.5).

4.2.2 Sampling Inspection Sampling inspection no&al-ly is initiated when the following requirements aresatisfied:

(a) All units of product are made according tothe same drawings and specifications under stable condi-tions of production. This requirement, which is termedhomogeneity, is usually satisfied when the productionprocess is not altered by innovation, significant changesin materials, strikes, retooling (other than that due toroutine changes to compensate for tool wear) or inter-ruptions other than those due to the end of the shift,day, or week.

(b) At least i consecutive units inspected bythe screening crew during 100% inspection are found freeof the defects concerned.

(c) None of the i consecutive units founddefect-free by the screening crew are found defectivebyisat

the checking inspector(s). When sampling inspectionbegun, screening is terminated and samples are takenthe frequency, f.

32

I


MIL-STD-1235B10 Decenber1981

4.2.3 Return to 100% Inspection Sampling inspectionshall be ternunated and 100% inspection shall be resumedupon the occurrence of one or both of the conditionsdescribed below:

(a) The production process is interrupted formore than three operating days, or the requirement of4.2.2(a) is otherwise not satisfied.

(b) Fewer than i consecutive defect-free sampleunits separate two defective sample units.

When 100% inspection is required, the flow of product iscurtailed until the screening crew can begin 100% inspec-tion. 100% inspection shall be continued until the re-quirements of 4.2.2 are met.

4.2.4 Change in Code Letter If it is necessary ordesirable to change Sampling Frequency Code Letters, thefollowing applies:

(a) If the change results in an increase inthe sampling frequency, f (and, of course, a decreasein tlw ciearance number, i), the change zay be zacieztthe next shift from a screening sequence to a samplingsequence or during a sampling sequence, whichever isthe earlier.

(b) If the change results in a decrease inthe sampling frequency, f (and, of course, an increasein the clearance number, i), the change may be made atthe next shift from a sampling sequence to a screeninqsequence or during a screening sequence, whichever isthe earlier. (At any time the change may be made byinitiating a screening sequence whose clearance number,i, will be that associated with the new code letter.)

4.2.5 Ineffective Screenin Whenever the checkinginsDector DrOdUCt found conform-ing-by the screening crew, ,the sbreening crew shallstart a new count of consecutive defect-free unita,and the actions described in 1.9.2 shall be carried out.

4.2.6 Long Periods of Screeninq If, during a periodof 100% inspection, a defect IS found before finding iconsecutive conforming units and the number of

.33



units screened is equal to or greater than the appro-priate value of S in Table 4-B, the supplier will notifythe consumer of this occurrence, and corrective actionshall be taken to improve the production process. Theconsumer may, at its option, suspend acceptance innnedi-ately or at any time thereafter during the period of 100%acceptance until the supplier corrects the cause(s) ofthe high rate of defective. After effective correctiveaction has been taken, 100% inspection shall be reiniti-ated.

34



,0

I

‘o

I

The screening crew inspects 100% of the units.

When i consecutive units are found free of thedefects concerned, the screeninq crew is releasedfrom 100% inspection, and

1The sampling, inspector inspects a fraction, f, ofthe units, where the sample units are selected in

1 a random manner.

When the sampling inspector finds one of the de-fects concerned,

w

The sampling inspector continues sampling butkeeps count of the number of sample-units in-spected after findinq the defect.

If the sampling inspec-tor finds i consecutivesample-units are free ofthe defects concerned,

4

If the sampling inspec-tor finds one of thedefects concerned, I

FIGURE 4-A. PROCEDURE FOR CSP-2 PLANS

35


w m

TABLE

4-A

Values

of

ifor

CSP-2

.Plans

Samp

Freq

AQL*

in

%Code

Ltr

f0.40

0.65

1.0

1.5

2.5

4.0

6.5

10.0

A1/2

80

54

35

23

15

97

4

B1/3

128

86

55

36

24

14

10

7

c1/4

162

109

70

45

30

18

12

8

D1/5

190

127

81

52

35

20

14

9

E1/7

230

155

99

64

42

25

17

11

F1/10

275

185

118

76

50

29

20

13

G1/15

330

220

140

90

59

35

24

15

H1/25

395

265

170

109

71

42

29

18

I,J,K

1/50

490

330

210

134

88

52

36

22

I0.53

0.79

1.22

1.90

2.90

4.94

7.12

11.46

IAOQL

in

%I I

•AQL~S

are

provided

as

indices

to

simplify

use

of

this

table,

bu

thave

no

oth

ermeaning

relative

to

the

plans.


.J 4 ,.

Samp

Freq

Code

Ltr

f

A1/2

B1/3

c1/4

D1/5

E1/7

F1/10

G1/15

H1/25

I,J,K

1/50

TABLE

4-B

Values

of

Sfor

CSP-2

Plans

—.

AQL*

in

%

0.40

0.65

1.0

1.5

2.5

4.0

6.5

10.0

145

105

68

45

32

20

19

11

322

235

151

100

70

42

33

27

473

352

288

138

106

63

46

34

746

461

296

181

141

76

62

42

902

687

431,

274

199

115

91

62

1380

987

608

386

292

154

132

91

1990

1480

946

566

440

243

200

127

3090

2265

1455

905

652

368

334

212

5400

3980

2540

1625

1165

642

601

352

0.53”

0.79

1.22

1.90

2.90

4.94

7.12

11.46

ADQL

in

%

*AQLVS

are

provided

as

indices

to

simplify

use

of

this

table,

but

have

no

other

meanino

relative

to

the

plans.

,0


●

!

MIL-STD-123SB10 December1981

inspection5.2.3 Return to 100% Inspection Samplingshall be ternunated and 100% inspection shall be-resumedif either or both of the conditions described belowoccur.

(a) The production process is interrupted formore than three operating days, or the requirement of5.2.2(a) is otherwise not satisfied.

(b) A unit having any of the defects concernedis found by the sampling inspector.

When 1008 inspection “is required, the’flow of product iscurtailed until the screening crew can begin 100% inspec-tion. 100% inspection shall be continued until the re-quirements of 5.2.2 are met.

5.2.4 Channe in Code Letter If it is necessary ordesirable to change Sampl>ng Frequency code Letters, thefollowing applies:

(a) If the change re6ults in an increase inthe sampling frequency, f (and, of course, a decreasein the clearance number, i), the change may be made atLhe next Shift 5T3Z a scree~inq sequence to a samplinqsequence or during a sampling sequence, whichever isthe earlier.

(b) If the chanue results in a decrease inthe sampling frequency, f (and, of course, an increasein the clearance number, i), the change may be made atthe next shift from a sampling sequence to a screeningsequence or during a screening sequence, whichever isthe earlier. (At any time the change may be made byinitiating a screening sequence whose clearance number,i, will be that associated with the new code letter.)

5.2.5 Ineffective Screening Whenever the checkinginspector finds a defect in the product found conform-ing by the screening crew, the screeninq crew shallstart a new count of consecutive defect-free units,and the actions described in 1.9.2 shall be carried out.

39


MI1-STD-1235B10 December1981

●

●

SECTION 5

CSP-T

5.1 FEATURES OF CSP-T

CSP-T is a multi-level continuous sampling pro-cedure which provides for alternating sequences of 100%inspection and sampling inspection. CSP-’Trequires areturn to 100% inspection whenever a nonconforming unitis discovered during sampling inspection, but providesfor a reduced sampling frequency upon demonstration ofsuperior product quality. CSP-T shall not be used forinspection for critical defects (see also 1.6.2). SeeFigure 5-A for a summary of the operation of CSP-T.Tables 5-A and 5-B list parameters associated with theprocedure.

5.2 DESCRIPTION OF PROCEDURE

5.2.1 Initiation of Production At the start of Pro-duction, each un~t of product shall be inspected by thescreening crew. Checking inspection shall be performed.concurrently at frequency f or more often on the unitspassed by the screeninq crew (see 5.2.5).

5.?.2 Sampling Inspection Sampling inspection nor-mally is ~nltlated when the followinq requirements aresatisfied:

[a) All units of product are made accordinqto the same drawings and specifications under stableconditions of production. This requirement, which istermed homogeneity, i’susually sat~sfied when the pro-duction process is not altered by innovation, signifi-cant changes in materials, strikes, retooling (otherthan that due to routine changes to compensate fortool wear) or interruptions other than those due tothe end of the shift,-day,, or week.

(b) At least i consecutive units inspected bythe screening crew during 100% inspection are found freeof the defects concerned.

(c) None of the i consecutive units founddefect-free by the screening crew are found defectiveby the checking inspector(s). When sampling inspec-tion is bequn, screening is terminated and samples aretaken at the frequency f. The sampling frequency maybe reduced subject to the conditions shown on Figure 5-A.

38


MIL-STD-l235B10 December19B1

5.2.6 Long Periods of Screenin~ If, during a periodof 100% inspection, a defect IS found before finding iconsecutive conforming units and the number ofunits screened is equal to or greater than the appropri-ate value of S in Table 5-B, the supplier shall notifythe consumer of this occurrence, and corrective actionshall be taken to improve the production process. Theconsumer may, at its option, suspend acceptance immedi-ately or at any time thereafter during the period of100% inspection until the supplier corrects the cause(s)of the high rate of defective. After effective correc-tive action has been taken, 100% inspection shall bereinitiated.

40


0’

HIL-STD-1235B10 December1991

START

+4

The screening crew inspects 100% of the units.

7

Nhen i consecutive units are found free of thedefects concerned,

1. .I

IThe screeninq crew is released from 100% inspec-tion and the sampling inspector inspects a frac-tion, f, of the units, where the units are select-ed in a random manner.

I The sampling inspector begir.sinspecting a frac-tion, f/2, of the units, which are selected in arandom manner. I

If the sampling inspec- If the sampling inspec-tor finds one of the deter finds i consecutivefects concerned, sample units are free of

the defects concerned,%

o 1A

J

I The sampling inspector begins inspecting a frac-tion, f/4, of the units, which are selected in arandom manner. I

I When the sampling inspector finds one of the de-fects concerned, I

FIGURE 5-A. PROCEDURE FOR CSP-T PLANS

41

—


Samp

Freq

Code

Ltr A B c D E F G

H

I

J,K

TABLE

5-A

Val

ues

of

ifor

CSP-T

Plans

f0.40

0.65

1.0

1.5

2.5

4.0

6.5

10.0

1/2

1/3

1/4

1/5

1/7

1/10

1/15

1/25

“1/50

1/100

87

116

139

158

189

.224 26

6

324

409

499

58

78

93

106

127

150

179

217

274

335

38

51

61

69

82

97

116

141

177

217

25

33

39

44

53

63

74

90

114

139

16

22

26

29

35

41

49

59

75

91

10

13

15

17

21

24

29

35

44

53

7 9

11

12

14

17

20

24

30

37

5 6 7 8 9

11

13

15

19

23

10.53.

.0.79

1.22

1.90

2.90

4.94

7.12

11.46

1’I

‘OQ

Lin%

I

●AQL’s

are

provided

as

indices

to

simplify

use

of

this

table,

but

have

no

other

meaning

relative

to

the

plans.


[

TABLE

5-B

Values

of

Sfor

CSP-T

Plans

;Smp

1

~req

AQL*

in

0:ode

itr

f0.40

0.65

1.0

1.5

2.5

4.0

6.5

10.0

A1/2

159

117

.77

52

34

22

13

12

B1/3

256

197

128

80

59

35

25

18

c1/4

379

253

167

103

78

43

38

24

D1/5

444

320

210

130

93

54

43

30

E1/7

725

460

289

168

137

81

59

34

F1/10

857

619

398

261’

189

104

88

58

G1/15

1254

900

.584

368

376

152

126

84

H1/25

1885

1396

923

545

421

235

198

122

I1/50

3283

2477

1604

1013

764

408

374

223

J,K

1/100

5753

4541

“2948

1754

1341

708

653.

391

0.53

0.79

1.22

1.90

2.90

4.94

7.12

11.46

AOQL

in

%

●AQLIS

are

provided

as

indices

to

simplify

use

of

this

table,

but

have

no

other

meaning

relative

to

the

plans.


MIL-STD-1235B10 December 1981

SECTIOX 6

CSP-V

6.1 FEATU.P.!?SOF CSP-V

CSP-V is a single-level continuous sampling pro-cedure which provides for alternating sequences of 100%inspection and sampling inspection. CSP-V requires a re-turn to 100% inspection whenever a nonconforming unit isdiscovered during sampling inspectim, but provides fora reduced clearance number upon ter,ozstration of superiorproduct quality. It can be beneficially applied in thosesituations where there is no at-$.mtage to reducing sam-pling frequencies in the good quality situation; forexample, when the inspector would merely kave more idletime if the samplinq frequency were reduced. CSP-V shallnot be used for inspection for critical defects (see also1.6.2). See Figure 6-A for a s,u?zsryof the operation ofCSP-V . Tables 6-A and 6B.list parameters associatedwith the procedure.

6.2 I?ESCRI?TION OF PROCEDURS

~-~.~ T-:&:a+:---..ALA ..Lul, C: ?roduct ion At the start of pro-duction, each unit of product shall be inspected by thescreening crew. Checking inspection shall be performedconcurrently at a frequency f or more often ~n the unitspassed by the screening crew (see 6.2.5).

6.2.2 Sampling Inspection Sampling inspection nor-mally is mltlated when the following requirements aresatisfied:

(a) All units of product are made according tothe same drawings and specifications under stable condi-tions of production. This requirement, which is termedhomogeneity, is usually satisfied when the pr~ductionprocess is not altered by innovation, significant changes ‘in materials, strikes, retooling (other than that due toroutine changes to compensate for tool wear) or inter-ruptions other than those due to tt,eend of the shift,~ay, Dr week.

(b) At least i (or x if appropriate) consecu-tive units inspected by the screening crew during 100%inspection are f~und free of the defects concerned.

44


!41L-STD-1235E10 December1981

(cl None of the i (or x if appropriate) con-secutive units found defect-free by the screening creware foun~ defective by the checking inspector(s). Whensamplinq inspection is begun, screeninq is terminatedantisamples are taken at the frequency, f.

6.2.3 Return to 100% Inspection Sampling inspectionshall be terminated and 10O% inspection shall be resumedif either or both of the conditions described belowoccur. The appropriate clearance number will be deter-mined according to the procedural rules shown inFigure 6-A.

(a) The production process is interrupted formore than three operating days, or the requirement of6.2.2(a) is otherwise not satisfiefl.

(b) A unit having any of the defects concernedis found by the sampling inspector.

When 100% inspection is required, the flow of product iscurtailed until the screening crew can beqin 100% in-spection. 100% inspection shall be continued until therequire!nents of 6.2.2 are met.

6.2.4 Chanqe in Co2e Letter If it is necessary ordesirable to chanqe Sampllnu Fre9ue~cY code Letters, thefollowing applies;

(a) If the change results in an increase inthe sampling frequency, f (and, of course, a decreasein the clearance number, i), the charge may be made atthe next shift from a screening sequence to a s~Plin9sequence or during a sampling sequence, whichever isthe earlier.

(b) If the change results in a decrease inthe samplinq frequency, f {and, of course, an increasein the clearance number, i), the change maY be made atthe next shift from a sampling sequence to a screeningsequence or during a screening sequence, whichever isthe earlier. (At ~y”time the chan~e may be made byLnitiatinq a screenlnq sequence whose cleaxance nurher,i, will be that associated with the new code letter.)

45


MIL-STD-123SBlIJDecember1981

6.2.5 Ineffective Screeninq Whenever the checkinginspector finds a defect m the product found conformingby the screening crew, the screening crew shall start anew count of consecutive defect-free units, and theactions described in 1.9.2 shall be carried out.

6.2.6 Long Periods of Screenin% If, during a periodof 100% inspection, a defect 1s found before finding iconsecutive conforming units and the numberofunits screened is equal to or greater than the appropri-ate value of S in Table 6-B, the supplier shall notifythe consumer of this occurrence, and corrective actionshall be taken to improve the production process. Theconsumer may, at its option, suspend acceptance immedi-ately or at any time thereafter durinq the period of100% inspection until the supplier corrects the cause(s)of the high rate of defective. After effective ‘cor-rective action has been taken, 100% inspection shall bereinitiated.

●

●

46

I


I- IL L->*” -A-J.U

10 December19P1

sTART#

I

I

tiThe screeninq crew inspects 100% of the units.

I

I\ihen i consecutive units are found free of thedefects concerned,

I

IThe screening crew IS released from 100% inspec-tion and the sampling inspector inspects a frac-tion, f, of the units, where the units are select-ed in a random manner.

I If the sampiinq ins5ec-

1

If i consecutive sampletor finds one of the de- units are free of thefects concerned defects concerned,

~ ::;n:~plinq inspector continues to inspect a frac--, of the randomly selected units.

I When the sampling inspector finds one of the de-fects concerned,

I The screening crew begins inspection 100%of theunits.

IIf a defect is found in

I

If x consecutive LInltsthe next x consecutive are free of tne defectsunits. concerned,

FIGURE 6-A. PROCEDURE FOR CSP-V PLANS

47

1


TABLE

6-A

Values

of

iand

xforCSP-V

Pla

ns

Samp

Freq

Code

AQI..* in

%

Ltr

f0.40

0.65

1.0

1.5

2.5

4.0

6.5

10.0

A1/2

60

39

27

18

12

96

20

3i

13

96

43

21

x

B1/3

96

63

42

27

18

12

96

32

i21

14

96

43

2x

c1/4

120

81

54

36

24

15

12

640

i27

18

12

85

42

x

D1/5

144

96

63

42

27

48

18

12

9i

32

21

14

96

43

x1:

L/7

177

120

78

51

33

21

15

959

i40

26

17

11

75.”3

x

F1./10

213

144

93

60

39

24

71

18

12

i48

31

20

13

86

4x

G‘,/15

258

174

.11.4

72

48

30

86

21

12

i58

38

24

16

10

74

x

![

1/25

318

213

138

90

60

36

24

15

i106

71

46

30

20’

12

85

x

I1/50

405

273

177

114

75

21

i135

91

59

38

25

;;

i:

7x

J1/100

498

333

216

138

90

54

39

24

i166

111

72

46

30

18

13

8x

K1/200

594

399

258

165

108

63

45

27

i198

133

86

55

36

21

15

9x

0.53

0.79

1.22

1.90

2.90

4.94

7.12

11.46

AOQL

in

%t ●AQL’s

are

provided

as

indices

t.;simplify

usc

of

this

table,

bu

thave

no

other

meaning

relative

to

the

plans.

●


a Ui

I

?ziii

p-Frcq

cnclc,

Ltr

———

.

A B c D E F G !( 1 !1 K

——

.—

F..=

——

—

.1/2

1/3

:./4

“,

1/5

1/1

:/10

1/15

:./25

:./50

3./?.00

1/200

T.N!3LF,6-B

Values

of

Sfor

CSP-V

Plans

—.

.——

AQL*

i~

?

0..40

0.65

1,0

1.s

2.5

4.0

6.5

10.0

_—

9R

65

<6

28

-. -1

c..

18

13

5

192

127

fi5

55

38

28

25

19

267

;~c;

i41

98

66

53

44

19

390

251

172

119

80

58

44

39

533

409

7.60

176

121

82

65

39

772

5.79

377

237

167

102

97

71

1165

857

563

357

249

158

139

71

1754

1327

848

537

427

254

198.

120

325S

2467

1~04

944

762

415

373

301

549?.

45(!8

2826

1741

1279

746

731

433

8931

7208

4670

2828

2516

1210

1192

659

0.53

0.79

1.22

1.90

2.90

4.94

7.12

11.46

AQQL

in

%—-.

.I%’&

n-+

mo 3A ::

●AQ

L9s

arc

provided

as

indices

to

simplify

usc

of

this

table,

but

have

no

other

meanin9

!-:

..-.

rela

tive

tcth

ep

lan

s:


MIL-STD-1Z35B10 December 19BI

7.1

7.2

7’.3

7.4

SECTION 7

DEFINITIONS

Acceptable Ouality Level [AQL) See 1.3.1

Average Outgoinq Dualitv [AOQ) See 1.4.1.1

Average Outaoina Quality Limit (AOOL) See 1.4.1.2

Checking Inspection Checking inspection is sam-plinq inspection performed bv the suPDlier on units ofprod~ct which hav& already b;en 100%”~nspected in orderto determine the effectiveness of the screening crew.This inspection is performed at the sampling rate f ormore often.

7.5 Clearance Number The clearance number, i, isthe number of consecutive conforming (i.e., defect-free)units in 100% inspection required prior to qualifyingfor inspection on a sampling basis.

7.6 Conforming Unit A conforming unit is one whichmeets the acceptance criteria established for the char-acteristic beino considered.

7.7 Continuous Samuling Inspection Continuous 5am-pling inspect~on IS the examination or testin? of unitsof product as thev move past an inspection station. &1 ythose units of product found by the inspector or screeninacrew to be nonconforming are rejected. The rest of theproduction, uninspected u~its as well as units found tobe conforming. is allowed to continue down the productionline as

7.8

7.9

7.10unit of

.Conforming material.

Critical Defect See 1.2.1.1

Critical Defective See 1,2.2.1

Defect A defect is any nonconformance of thep~ with specified requirements.

I 7.11 Defects Concerned The defects being inspected

I for while using the samplinq plan.

I

50



7.12 Defective A defective is any unit of ?roductwhich conta~ns one or nmre defects.

7.13 Inspection Inspection is the process of mea-suring, exanmnlng, testing, or othe~ise comparina theunit of product with the requirements.

7.14 Inspection by Attributes Inspection by attri-butes is inspection whereby certain characteristics ofunits of products are inspected and classified simPIYas conforming or not conforming to the specifiedrequirements.

7.15 Inspection by Defect Class When one samplingplan is assoc~ated with mspectlon for several kinds ofdefects collectively and each unit of product inspectedis inspected for each of the defects in the class.

7.16 Inspection’by Individual Defect When one Sam-pling plan is associated with inspection for a singledefect, or when a sampling plan is applied to each ofseveral defects independently.

7.17 Major Defect See 1.2.1.2

7.18 Major Defective See 1.2.2.2—.— _._—.

7.19 Minor Defect See 1.2.1.3

7.20 Minor Defective See 1.2.2.3

7.21 Moving Product The term “moving product” refersto product which 1s flowing past the inspection Station.In the typical case the product moves on a conveyor beltor line; however, it may be moved in tote boxes, buggiesor other conveyances which are operatetimanually or bymobile materials-handling equipment.

7.22 Multi-level A multi-level plan consists ofperiods 0? 10 O% ins~ection and of sampling inspectionat various rates which reflect past inspection results.

7.23 N The specified number of units to which CSP-Fis to be =pplied.

51


MIL-STD-123SB10 December19EI

7.24 One Hundred Percept Inspection One hundred per-cent inspect~or means the inspection of every unit 0!prcduct for the defects concerned listed for an inspec-tier. statio~. The two terms, screening and 100% inspec-tion., aze useciinterchangeably in this standard.

7.25 Process Average The process average (PA) isdefined as the percent defective of product submitted bythe supplier for original inspection. Original inspec-tion is the first inspection of a particular quantity ofproduct as distinguished fromwhich has been resubmitted.

7.26 Production Intervalnormally a shift; It can be acertzin-that shift changes doduct , but shall not be longer

the inspection of product

A production interval isday if it is reasonablynot affect quality of pro-than a day.

7.:7 Samp:irg Frequency (f) The sampiing frequency,f, is the desired ratio between the number of units ofproduct randomly selected and inspected at an inspectionstation’ and the number of units passing the inspectionstation during periods of sampling inspection. In thisStdndard, each f is expressed as a fraction of the form,1~~: 1~25: 1,,’50:etc. The procedure used in selectingthe sar,zlcur.~tsshould give each unit of product pre-sc.nte~~LIi]J~pcxiods of saiipling inspection an equalchance of bell:g selected and inspected.

7.2Z Sampling IIISDeCLIO1l Sampling inspection in thisStandarci means the inspection fcr the defects concernedwhere the units selected for inspection are selected bysampling.

7.29 Screeniny Screeninq is 100% inspection whereall defective wnlts are removed from.the production flow.The two terms, screening and 100% inspection, are usedinterchar.geably in this Standard.

●

7.3C Single-level P. sim.gle-level plan consists of

alternating periods of 10C% inspection and sampling in-~pec~io; v:~~rein the sampling rate is constant.



I 731 ‘nit ‘f ‘roduc’ The unit, of product is the thinS beinginspected in order to determine its classification as iefectiveor nondefective or to count the number of de fe~ts. ” It ma”,’be asingle article, a pair, a set, a length, an area, an oper; ti~o, avolume, a component of an end product, or the end pr~d~ct itself.The unit of product may or may not be the same as the unit ofp~lrchase, supply, production, or shipment.

“0

II

●

C,.lstodian:Army - Al?I!avy J OS

Review activities:Army - MT, EAlavv - AS, YD, SH, MCDs~ . Es

Llscr activities:Army - ME

Pr?paring Activity:Army - AR

(Project QCIC !3P19)

53


INSTRUCTIWS: III s emuinuing●ffort to nukt our stcndwdizatio. dorume.w ti:!cr, tbrDoDpmtidea U& form for w in

.ubmiming commenm and wggutimu for improvement. AI] use” of militiry .Ia.d.rdization docurnenu w inriwd to pmride

CUquliofu, 711u form KMY be debched, folded along the kinea indicsted, uped along kfw IMU + (00 NOT sTAPLE), md

nuiltd. 1. block 5, lx u specific u pmtible ●bout particular problem ucu such u wording which fel.imd inwpmmlion, wu

ma ri[id, rntricli?e. la.e, smbiruow, or vu incompatible, ●nd gi.e ptormccd word@ cbmxrs ti,cb -uld alletiw Ibe

woblem Enker in block 6 my rcmuh not related LO ● wrcific p~ph or tie dw=nt. If bl=k 7 u rued OuL. m

●ckho.ledgement will bt mailed 10 you tithin 30 days to let you kn.a. Eh.t your COU.IU?IIU wert rutised and uc bckg

cnrnidemd

NOTE: TM. [mm may not & used to request copia of doc.me”lt, nor LO mqueat .tivem, d~kior.i, or dm’ific.kion of

Spccifiution mquiremenuon current conlmcu. %mments .ubmitted on tiu form do nst cmmitute or imply .ukb.xiution

10 wmi- any portion of the referenced dc.cumenl(d or to amend contmctud requimmenti.

I

,Fold .1.”, ,hu 11”.,

OEpARTMENT OF THE ARMy

1111110FFU3AL WSIMESPENAL,, PO. .R, ”ATE “SE .,~ BUSINESS REPLY MAIL,!.51CLASS PE. MIT NO l>~? WA SHIN G1ON O C

POSTAGE WILL BE PAID BV THE DEPARTMENT OF THE ARMY

Commander

US Army Armemeni Research and Development Comnand

ATTs : DFUM.R-TST-S

Dover, XJ D78D1

NO ●OSTAGEwEcESAh FIVBPMAILED

ONTWEUNITED STATI?S


.STANDARDIZ4TION DOCUMENT IMPROVEMENT PROPOSAL(See Instrucfiom - RrvcrsrS;dt)

.DOCUMEN1 NUMBER 2, DOCUWEUT TITLE

F4.”.3., R.,,O ..,. ,., ..,. m-...,, o.

TVPEOF OnQtiN, zAT,owtMg, bw,,

a VENDOR

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I rc M. IL!NG .00 RESS 4S!-.,. C!,. . s,.,,. 7.,? cod, ! - 0.,,..., IQ OATk OC SUUMISSIO% ,YVMMDD,

1.,~

00J”R.1426 PREVIOUS EOIT80N IS OBSOLETE.


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