1、Designation: D 6674 01Standard Guide forProficiency Test Program for Fabrics1This standard is issued under the fixed designation D 6674; 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 parenth
2、eses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.INTRODUCTIONProficiency testing is the use of interlaboratory test comparisons to determine the performance ofindividual laboratories for specific tests and to mon
3、itor the consistency and comparability of alaboratorys test data.Participation in proficiency testing programs provides laboratories with an objective means ofassessing and demonstrating the reliability of the data they are producing. Although there are severaltypes of proficiency testing programs,
4、they all share the common feature of the comparison of testresults obtained by two or more laboratories.One of the main uses of proficiency testing programs is to assess laboratories ability to performtests competently. This will involve the preparation of the test specimens, calibrating or validati
5、ng thetesting equipment, performing the tests and reporting the data.Bodies assessing the technical competence of testing laboratories normally require or expectsatisfactory participation in proficiency testing as evidence of a laboratorys ability to produce reliabletest results.1. Scope1.1 This gui
6、de outlines the Proficiency Test Program forFabrics. Elements for planning the proficiency test program,selecting the sample fabrics to be used, the testing protocol,and the calculations for the data to be reported are included inthis practice.1.2 The planning of the proficiency test program require
7、s ageneral knowledge of testing of textile fabrics and statisticalprinciples included in the analysis of the data.1.3 This guide is designed to meet the quality systemsproficiency and competence requirements of participating labo-ratories. This program is not accredited to any internationalstandard.
8、1.4 The instructions in this guide follow the logic of fullscale laboratory tests as described in Practice D 2904 andGuide E 1301, except with this new guide placing its emphasison proficiency testing.1.5 Procedures given in this guide are applicable to methodsbased on the measurement of discrete me
9、asurement data andgrades or scores.2. Referenced Documents2.1 ASTM Standards:D 123 Terminology Relating to Textiles2D 737 Test Method for Air Permeability of Textile Fabrics2D 1230 Flammability of Apparel Fabrics, 16CFR 16102D 2261 Test Method for Tearing Strength of Fabrics by theTongue (Single Rip
10、) Procedure Constraint Rate of Exten-sion (CRE) Tensile Testing Machine2D 2904 Practice for Interlaboratory Testing of Textiles thatProduces Normally Distributed Data2D 2906 Statements on Precision and Bias for Textiles2D 3775 Test Method for Fabric Count of Woven Fabric2D 5034 Test Method for Break
11、ing Strength and Elongationof Textile Fabrics (Grab Test)3D 5035 Test Method for Breaking Force and Elongation ofTextile Fabrics (Strip Method)3D 6545 Flammability of Textiles Used in Childrens Sleep-wear3E 1301 Guide for Proficiency Testing by InterlaboratoryComparisons43. Terminology3.1 For defini
12、tions of textile and statistical terms used in thispractice, and discussions of their use, refer to TerminologyD 123 and appropriate textbooks on statistics.3.2 DefinitionsThe relevant definitions are from Termi-nology D 123, and are the most relevant and applicable beingquoted for the purposes of t
13、his practice.3.2.1 accuracy, nof a test method, the degree of agree-ment between the true value of the property being tested (or1This guide is under the jurisdiction of ASTM Committee D13 on Textiles andis the direct responsibility of Subcommittee D13.93 on Statistics.Current edition approved May 10
14、, 2001. Published August 2001.2Annual Book of ASTM Standards,Vol 07.01.3Annual Book of ASTM Standards,Vol 07.02.4Annual Book of ASTM Standards, Vol 14.02.1Copyright ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.accepted standard value) and the average of many observati
15、onsmade according to the test method, preferably by manyobservers. D 29063.2.2 batch sample, nthe material(s) used for the profi-ciency test study taken from a common roll or garment lot anddistributed to the participants.3.2.3 bias, nin statistics, a constant or systematic error intest results.3.2.
16、4 calibrate, nto determine and record the relationshipbetween a set of standard units of measure and the output of aninstrument or test procedure.3.2.5 precision, nthe degree of agreement within a set ofobservations or test results obtained as directed in a method.3.2.5.1 DiscussionThe term “precisi
17、on,” delimited invarious ways, is used to describe different aspects of precision.This usage was chosen in preference to the use of “repeatabil-ity” and “reproducibility.”3.2.6 precision, nunder conditions of between-laboratoryprecision, the multi-laboratory single sample, single operator-apparatus-
18、day (within laboratory) precision of a method; theprecision of a set of statistically independent test results all ofwhich are obtained by testing the same sample of material andeach of which is obtained in a different laboratory by oneoperator using one apparatus to obtain the same number ofobserva
19、tions by testing randomly drawn specimens over theshortest practical time interval. For a more detailed definition,refer to D 2906.3.2.7 proficiency testing, ndetermination of the laboratorytesting performance by means of interlaboratory comparisons.3.2.8 program coordinator, nthe person(s) responsi
20、ble formanagement of all logistical issues, data collection, and reportpreparation.3.2.9 repeatability, nin statistics, the distribution of sev-eral measurements on the same part by one operator with thesame gage.3.2.10 reproducibility, nin statistics, the distribution ofseveral measurements on the
21、same part by several operatorswith the same gage.3.2.11 sample, n(1) a portion of material which is takenfor testing or record purposes. (2) a group of specimens used,or of observations made, which provide information that can beused for making statistical inferences about the population(s)from whic
22、h the specimens are drawn.3.2.12 specimen, na specific portion of a material or alaboratory sample upon which a test is performed or which isselected for that purpose.3.2.13 test result, na value obtained by applying a giventest method, expressed as a single determination or a specifiedcombination o
23、f a number of determinations.3.2.14 testing laboratory, nlaboratory that performs tests(including calibration) (also referred to as “participating labo-ratory,” or just “laboratory”).4. Significance and Use4.1 Proficiency testing is a means of securing estimates ofthe variability of results obtained
24、 by different laboratoriestesting homogeneous materials taken from batch samples whenfollowing procedures prescribed in a specific test method.4.1.1 For the purpose of this guide, homogeneous materialsare considered to be laboratory samples cut from the samebatch sample (roll or garment lot) and sel
25、ected at random forthe participant laboratories.4.2 This proficiency test program is to be considered afull-scale interlaboratory test, in which a reasonably largenumber of laboratories participate by testing a series ofmaterials using one or more operators per laboratory and reportthe data for anal
26、ysis.4.2.1 For the purposes of this guide, Full Scale LaboratoryTest is defined in Practice D 2904. This is not to be confusedwith the full scale testing terminology and definitions whichappear in other test methods, such as flammability, thatdescribe the size of the specimens being tested.4.3 The s
27、tatistical data generated by this practice provideinformation needed to exhibit participation in a formal profi-ciency test study.4.4 All data are submitted to the program coordinator atASTM Headquarters for the preparation and distribution of theproficiency testing program reports. All laboratory d
28、ata areconfidential with no disclosure of lab identity except for eachparticipants own laboratory. Published reports contain alllaboratory test data (coded), statistical analysis of test data,charts plotting test results versus lab code, and other informa-tion.5. Materials to be Used in Study5.1 Mec
29、hanical Testing ProgramThree types of materialsare to be included in the study. The materials shall be describedas light, medium and heavy as defined by the breakingstrengths. The materials to be used for this study shall beselected by the Subcommittee D13.93 with assistance fromparticipant laborato
30、ries and pertinent subcommittees. An ac-credited laboratory selected by the Subcommittee D13.93 shallact as host and maintain these materials. The host laboratoryshall not be held responsible for the performance of the testmaterials at the participant laboratories.5.2 Flammability Test ProgramAt lea
31、st seven types offabrics are to be available for the study, not all of which will beused at the same time. The materials shall be described by fibertype, construction type (woven, knit, nonwoven), surfacecharacteristics and fabric weight as defined by the flammabilitycharacteristics. The fabrics to
32、be used for this study shall beselected by the Subcommittee D13.93. An accredited labora-tory selected by the Subcommittee D13.93 shall act as the hostand maintain these fabrics. The host laboratory shall not beheld responsible for the performance of the materials at theparticipant laboratories.6. D
33、istribution of Test Materials6.1 The proficiency test program is designed for the testmaterials to be distributed at a minimum two times eachcalendar yearFebruary and August. Each participating labo-ratory shall apply through ASTM Headquarters for inclusion inthe program.6.2 The materials will be di
34、stributed by having the hostlaboratory cut fabric samples from each batch roll or garmentlot. The samples will be identified, labeled and mailed to eachparticipating laboratory. ASTM Headquarters will provideD 66742detailed instruction sheets and mailing labels to the hostlaboratory.6.3 Instructions
35、 for testing, recording data and return; formsand fabric samples will be mailed together as instructed.7. Selection of Test Methods7.1 For Mechanical TestingThe test methods shall beselected and monitored by the Subcommittee D13.93. Theprotocol of this guide may not include the entire scope ofmethod
36、s used for testing fabric, but will include at least onemechanical test from the fields used to define woven fabricproperties such as construction, air permeability and strength.Other methods may be added or deleted as directed by D13.93with input from ASTM staff, participating laboratories, andpert
37、inent Sub-Committee.7.1.1 The methods to be used for this guide are as follows:D 737 Air Permeability of Textile FabricsD 2261 Tearing Strength By Tongue Method (CRE Type Instrument)D 3775 Fabric Count of Woven FabricD 5034 Breaking Strength and Elongation of Textile Fabrics (GrabTest)D 5035 Breakin
38、g Strength and Elongation of Textile Fabrics (StripTest)7.2 For Flammability TestingThe test methods shall beselected and monitored by the subcommittee D13.93. Theprotocol of this guide may not include the entire scope ofmethods used for testing fabrics, but will include at least oneflammability tes
39、t from the fields used to define characteristicsof the end use product.NOTE 1D13.52 is preparing two additional testing protocols to beused in conjunction with the flammability tests. The criteria are beingestablished for lab personnel to identify the types of product being testedand a comprehensive
40、 exam for the scope of testing.7.2.1 The methods to be used for this guide are as follows:D 1230 Flammability of Apparel FabricsD 6545 Flammability of Textiles Used in Childrens Sleepwear8. Sampling8.1 Sampling of MaterialsThe host laboratory shall allo-cate enough material to provide for all partic
41、ipating laborato-ries to perform the complete scope of testing for the program.8.2 Numbers of DeterminationsEach participating labshall prepare the test specimens and number of determinations(replicates) as directed by the proficiency testing program.9. Data Reporting9.1 All data shall be reported a
42、s instructed using the formssupplied with the material package.9.2 Outlying ObservationsAll data shall be reported.Exceptions to this general policy should be made only whenassignable causes for deletion of a test value are present. Incases where there is no assignable cause for a test value beingou
43、t of line, the test value shall be retained and reported.10. Report10.1 Table of Results pages provides a listing of laboratorieswith corresponding test results. Each laboratory is identified bya randomly selected code with the same laboratory codeapplying throughout the entire report. To maintain c
44、onfidenti-ality of test data, the identification of lab codes will not bereleased from ASTM. Therefore, program participants will beable to identify only their own test data. The laboratoryidentification code may change with subsequent reports. Eachtable page contains a heading identifying the metho
45、d and testfabric.10.2 Lab Average column contains the lab average asreported to ASTM by the participating laboratories.10.3 The Lab Range column represents the difference be-tween the labs lowest and highest of the raw data results.10.4 Description of Z-Score ColumnThe Z-Score column(comparable to t
46、he Students t statistic) reports each labsdeviation in units of standard deviations. The Z Score is thecalculated number of standard deviations a sample mean isabove or below the population mean. The criteria for the ZScores will be as follows:Z 3 = unsatisfactoryZ-Scores outside this range should o
47、ccur only about one timein twenty, if a laboratory has average capability running themethod. Laboratories should strive to obtain Z Score valuesclose to zero. The Z-Score is calculated as follows:Z Score 5lab average total average! / total standard deviation10.5 Identification of Outlier DataDuring
48、the analyticalreview of the data it was observed that when including all datain the calculation of the Overall Average and Std. Deviation, insome cases, the averages and standard deviations are adverselyaffected by outlier data. Therefore, through two iterations ofcalculations, labs who had a Z-Scor
49、e Value of 6 3 or greaterhave been asterisked in the table. These data, while stillincluded in the tables, have not been included in the statisticalanalysis. This step of excluding data is only performed throughtwo iterations. After the second iteration, all remaining datahave been included in the resulting statistical analysis.10.6 FlagsThis column contains reference to data outsideeither three standard deviations or the upper limit of the RangeChart. A “1” indicates that the labs average exceeds 3 standarddeviations, a “2” indicates that the lab