1、Designation: D4968 16D4968 17Standard Practice forAnnual Review of Test Methods and Specifications forPlastics1This standard is issued under the fixed designation D4968; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of l
2、ast revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This practice is intended to assist the subcommittees and sections of Committee D20 on Plastics with the process ofsta
3、ndards evaluation during the five-year review mandated by ASTM or when changes to test methods and specifications arerequired. It is intended to complement the Form and Style for ASTM Standards (“Blue Book”) not replace it.NOTE 1There is no known ISO equivalent to this standard.1.2 This internationa
4、l standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2
5、. Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to PlasticsD5740 Guide for Writing Material Standards in the Classification FormatE177 Practice for Use of the Terms Precision and Bias in ASTM Test MethodsE456 Terminology Relating to Quality and StatisticsE691 Practice for Conduct
6、ing an Interlaboratory Study to Determine the Precision of a Test MethodE2653 Practice for Conducting an Interlaboratory Study to Determine Precision Estimates for a Fire Test Method with FewerThan Six Participating LaboratoriesE2935 Practice for Conducting Equivalence Testing in Laboratory Applicat
7、ionsForm and Style for ASTM Standards (Blue Book)3. Terminology3.1 DefinitionsFor definitions of terms that appear in this practice relating to plastics, refer to Terminology D883.3.2 For definitions of terms that appear in this practice relating to quality and statistics, refer to Terminology E456.
8、3.2.1 Repeatabilityprecision under repeatability conditions.3.2.2 Reproducibilityprecision under reproducibility conditions.3.2.3 Repeatability Limitthe value below which the absolute difference between two individual test results obtained underrepeatability conditions may be expected to occur with
9、a probability of approximately 0.95 (95 %).3.2.4 Reproducibility Limitthe value below which the absolute difference between two individual test results obtained underreproducibility conditions may be expected to occur with a probability of approximately 0.95 (95 %).3.3 Guidelines for terminology in
10、standards that are referenced in model codes issued by either the The International CodeCouncil (ICC) or the National Fire ProtectionAssociation (NFPA) are based on guidance originally provided by one of the regionalmodel building codes (BOCA) and are given has issued guidelines for standards that a
11、re appropriate for reference in ICC codes,which include the requirement that they shall be written in Appendix X1.mandatory language.3.3.1 In practice, the key issue is to avoid using the terms “may” and “should,” except within definitions, appendixes andnon-mandatory notes.1 This guide is under the
12、 jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.90 on Executive.Current edition approved April 1, 2016Aug. 1, 2017. Published April 2016August 2017. Originally approved in 1989. Last previous edition approved in 20152016 asD4968 - 15.D4968 - 16. D
13、OI: 10.1520/D4968-16.10.1520/D4968-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an
14、 ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. I
15、n all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Sig
16、nificance and Use4.1 It is the intention of this practice, in addition to the Form and Style for ASTM Standards, to assist persons revising testmethods and specifications in Committee D20 to ensure that all required elements are included and that the revised document ispresented in the most user-fri
17、endly manner possible.4.2 This practice is intended for use by Committee D20 when test methods and specifications under its jurisdiction are revisedbecause of technical changes or upon five-year review.4.3 The flowchartsfigures in Annex A1 show contain three flowcharts. Fig. A1.1 is a flowchart that
18、 shows the review processand for standards that have been revised or reapproved recently. Fig.A1.2 is a flowchart for standards that have neither been revisednor reapproved within five years of a new review. Fig. A1.3 is a flowchart for the precision and bias process in outline form.4.4 Specific ins
19、tructions to be followed when revising Committee D20 documents are given in this practice.4.5 The model precision and bias (P and B) statements included in Annex A3 were developed to standardize the presentationof data.5. Evaluating the Need for Revisions5.1 Society regulations require that all D20
20、standards be reviewed in detail every five years. Ballots to revise individual sectionsof a document (which have the potential to change the date of issue) do not absolve the responsible D20 subcommittee from therequirement to conduct the detailed review every five years. Begin the review for revisi
21、on, reapproval, or withdrawal at least oneyear prior to the required revision year, that is, four years after the last full review. The date of the last complete document reviewmust be listed in the Summary of Changes section at the end of the document.5.2 The goal of the review process is to determ
22、ine if the document under review is to be balloted for:5.2.1 Reapproval without change,5.2.2 Reapproval with editorial changes,5.2.3 Revision with technical changes, or5.2.4 Withdrawal.5.3 A flowchart Two figures with flowcharts for review of plastics standard test methods or specifications isare fo
23、und in AnnexA1.5.3.1 The flowchart in Annex A1Fig. A1.1 applies only to reviews of standards that have either been revised or have beenreapproved less than five years before any new review.5.3.2 When a standard test method or a standard specification has neither been revised nor reapproved for at le
24、ast five years anew ballot is required required, in accordance with Fig. A1.2 and the flowchart in Annex A1Fig. A1.1 does not apply.5.3.3 The following sections describe the details for each step of the flowchart.flowcharts.5.3.4 With the permission of the Section or Subcommittee chairman, as approp
25、riate, a task group is formed with a task groupchairman to head it.The task group shall be composed of either one person or a small group.The subcommittee chairman generatesa project number to help track the progress. The task group chairman registers the project with ASTM through the website andan
26、ASTM Work Item number is generated. This WK number will appear on ballots.5.3.5 Is it Recommended that the Standard Be Withdrawn?If the examination of the standard indicates that it is obsolete orbasically flawed in light of more recent knowledge, ballot for withdrawal. Ballot for withdrawal is also
27、 in order if the standard hasbeen replaced by a more current standard.5.3.6 Are changes required?If the review of the standard using the instructions in this document and the current version ofthe ASTM Form and Style for ASTM Standards (Blue Book) indicate that no changes are needed, it is recommend
28、ed that thestandard be balloted for reapproval without change.5.3.7 Are Changes Editorial?If the subcommittee, section, or task group considers the intended changes to be editorial innature, the appropriate standards editor at ASTM Headquarters shall be consulted. If the changes meet the qualificati
29、ons foreditorial revision, within a five-year period since last publication, the standard can be editorially changed without balloting.balloting, as shown in Fig.A1.1. Such a revised standard will be published with an indication that it has been reissued with editorialchanges. However the document m
30、ust still be balloted for revision or reapproval at least every five years regardless of whetherit has been reissued with editorial changes.changes, and the process shown in Fig. A1.2 shall be followed.5.3.8 Is Technical Revision Necessary?If it is decided that the changes needed in the standard mod
31、ify the technical contentin any way, or if the review using this practice finds missing elements, technical changes shall be balloted. If major changes areneeded, a subcommittee ballot is recommended. Otherwise a concurrent subcommittee, Main Committee, and Society ballot isrecommended, providing th
32、is approach is approved by the main committee chairman and the subcommittee chairman or by asimple majority vote of the membership of the main committee and subcommittees.5.3.9 Model Precision and Bias (P and B) Statement:5.3.9.1 It is a requirement of ASTM that all test methods have a precision and
33、 bias section. For test methods that produce anumerical test result, an interlaboratory study (ILS, round robin) shall be conducted. Practice E691 describes the recommendedpractice for conducting an ILS to determine the precision of a test method, when six or more laboratories are involved.D4968 172
34、5.3.9.2 Practice E691 requires a minimum number of six laboratories generating usable data for a round robin for an acceptableround robin.As a result, Practice E691 is not applicable in all cases. Other statistical practices are appropriate for use if they yieldequivalent information. It is recommen
35、ded that the statistical practice used be reviewed by Subcommittee D20.13 on Statistics.5.3.9.3 If an ILS (round robin) cannot be accomplished prior to initial balloting of a test method, single-laboratory data mustbe used in the P and B statement. Use the model statement in Annex A3 as a model for
36、such statements and follow the guidancefrom the ASTM Form and Style for ASTM Standards. No test method shall remain a valid ASTM standard without at least asingle-laboratory P and B statement after a five year period from publication.5.3.9.4 ASTM International requires that an ILS study (round robin
37、) be performed, if possible, within five years of the testmethods initial publication. If an insufficient number of laboratories is available to complete a round robin by the five-year review,the model statement in Annex A3 is still acceptable, but a statement modeled after the “Type B” statement in
38、 Annex A3 shall beadded.5.3.9.5 When acceptable ILS (round-robin) data has been developed, it shall be written using a statement modeled after the“Type C” statement in Annex A3 and it shall be balloted for approval as a technical change. Documentation for the round robinshall be assembled in a techn
39、ical report and submitted to the staff manager. A footnote documenting the report number shall beincluded in the standard.6. Revising the Standard6.1 Keep the audience in mind.6.1.1 There are many different users ofASTM standards. When revising documents, write the standard to be of use to the prope
40、raudience. A standard can be used by such diverse users as design engineers, product specifiers, quality control persons, testinglaboratory managers, and technicians who will perform tests and all of their requirements need to be taken into account.6.1.2 Keep in mind, however, that certain sections
41、of the documents are directed at specific audiences. For example, theprocedures section of a test method will primarily be used by the technician who does the test. It is recommended that this sectionbe written in an imperative mood giving direct instructions on how to do the test, just as it would
42、be done if the standard werespeaking to the person. It is recommended not to add unnecessary explanations in the mandatory sections of the standard but togive clear and concise instructions. It is recommended that explanations that are not needed for conducting the test be, preferably,included in an
43、 appendix or in an explanatory note.6.1.3 Sections such as the scope are to give direction to the user on how and for what the standard is to be used. Setup andcalibration will be used by a test laboratory manager, and so forth. For each section, it is essential to consider the potential userand to
44、write that section to give the most direct and usable information to that potential user in the most concise and understandablemanner possible.6.2 Whenever a new standard is developed, or revisions to an existing standard are prepared for ballot, a Work Item must beregistered with ASTM at the ASTM w
45、eb-site (www.astm.org). When the Work Item is registered with ASTM an e-mail will besent to the technical contact with a link that permits the download of an electronic copy of the current standard. It is recommendedto use the “track changes” function in MS Word to show changes. Deleted text will be
46、 shown as struck out. New text will be shownas underlined. Be aware that it is possible that the paragraph numbers and their references will change as a result of these edits.6.3 Whenever a document is revised and circulated for ballot, it must be accompanied by a cover letter that explains the purp
47、oseof the ballot.6.4 When circulating a standard for ballot, the standard shall have the following working caveat in bold print on the front pageof the revision draft:THIS DOCUMENT IS NOT AN ASTM STANDARD; IT IS UNDER CONSIDERATION WITHIN AN ASTMTECHNICAL COMMITTEE BUT HAS NOT RECEIVED ALL APPROVALS
48、 REQUIRED TO BECOME AN ASTMSTANDARD. IT SHALL NOT BE REPRODUCED OR CIRCULATED OR QUOTED, IN WHOLE OR IN PART,OUTSIDE OF ASTM COMMITTEE ACTIVITIES EXCEPT WITH THE APPROVAL OF THE CHAIRMAN OF THECOMMITTEE HAVING JURISDICTION AND THE PRESIDENT OF THE SOCIETY. COPYRIGHT ASTM, 100 BarrHarbor Drive, WEST
49、CONSHOHOCKEN, PA, 19428-2959 ALL RIGHTS RESERVED.6.5 Reference the Form and Style for ASTM Standards for detailed information regarding the form and style for the document.6.6 The standard shall be reviewed to ensure that all procedures, directions, instructions, etc. are written as mandatoryrequirements. Explanatory material, intended either for emphasis or for offering informative suggestions not properly part of thestandard, shall be incorporated as notes or appendixes and is not required to be written in mandatory language.6.7 Documents that have been developed for, o
