ASTM_D_3992_-_94_2012e1.pdf

Designation:D399294(Reapproved 2012)1Standard Specifications forFineness of Wool Top or Mohair Top and Assignment ofGrade1This standard is issued under the fixed designation D3992;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 parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1NOTEThe terminology section was updated in July 2012.1.Scope1.1 These specifications are applicable in the classification,by fineness grade,of the fiber in wool top,mohair top,woolyarns,mohair yarns,wool fabrics,and mohair fabrics of theworsted type.NOTE1For fineness specifications for wool,mohair,and alpaca,referto Specifications D3991 and D2252.2.Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD2130 Test Method for Diameter of Wool and OtherAnimalFibers by MicroprojectionD2252 Specification for Fineness of Types of AlpacaD3991 Specifications for Fineness of Wool or Mohair andAssignment of GradeD4845 Terminology Relating to Wool2.2 Federal Standards:Official Standards of the United States for Grades of WoolTop,Section 31.1003Measurement Method for Determining Grade of Wool Top,Section 31.3013Official Standards of the United States for Grades of MohairTop,Section 32.1004Measurement Method for Determining Grade of MohairTop,Section 32.30243.Terminology3.1 For all terminology related to D13.13,refer to Termi-nology D3991.3.1.1 The following terms are relevant to this standard:average fiber diameter,fineness,grade,mohair,top,wool.3.2 For all other terminology related to textiles,refer toTerminology D123.4.Requirements4.1 The grade of wool top shall conform to Table 1.4.2 The grade of mohair top shall conform to Table 2.5.Significance and Use5.1 These specifications are considered satisfactory for clas-sifying wool top or mohair top by grade and provide a basis foracceptance of commercial shipments.6.Test Method6.1 Test the material as directed in Test Method D2130.Measure at least the minimum number of fibers needed toattain confidence limits of the mean within 60.4 m at aprobability level of 95%(see Annex A1 of Test MethodD2130).7.Assignment of Grade7.1 Compare the observed average fiber diameter and fiberdiameter distribution,determined as directed in Section 6,withthe specifications for the various grades for the material beingtested in Table 1 or Table 2.Assign the grade that correspondsto the average fiber diameter and fiber diameter distributionrequirements specified in Table 1 for wool top or Table 2 formohair top.If the observed average diameter and fiber diam-eter distribution correspond to a single grade,assign that grade.If the fiber diameter distribution does not meet the require-ments for the grade to which the average fiber diametercorresponds,assign a dual grade designation,the seconddesignation being one grade coarser than the grade to which theaverage fiber diameter corresponds.Assignment of grade isillustrated by the examples in 7.1.1 and 7.1.2.7.1.1 Wool Top:7.1.1.1 Example 1Average fiber diameter,28.10 m;fiberdiameter distribution;30.0 m and under,64%;30.1 m andover,36%;50.1 m and over,1%:grade designation,56s.1These specifications are under the jurisdiction of ASTM Committee D13 onTextiles and are the direct responsibility of Subcommittee D13.13 on Wool and Felt.Current edition approved July 1,2012.Published August 2012.Originallyapproved in 1981.Last previous edition approved in 2006 as D3992 94(2006).Replaces D472 and D1381.DOI:10.1520/D3992-94R12E01.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Federal Register,Vol 33,No.248,Dec.21,1968,pp.1907319076.4Federal Register,Vol 38,No.4,Jan.8,1976,pp.964967.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 7.1.1.2 Example 2Average fiber diameter,28.10 m;fiberdiameter distribution;30.0 m and under,61%;30.1 m andover,39%;50.1 m and over,2%:grade designation,56/54s.7.1.2 Mohair Top:7.1.2.1 Example 1Average fiber diameter,32.60 m;fiberdiameter distribution;40 m and under,83%;40.1 m andover,17%;50.1 m and over,3%:grade designation,28s.7.1.2.2 Example 2Average fiber diameter,32.60 m;fiberdiameter distribution;40 m and under,79%;40.1 m andover,21%;50.1 m and over,4%:grade designation,28/26s.7.2 Interpretation of ResultsThe true average fiber diam-eter of a lot of wool top or mohair top can be determined onlyby measurement of every fiber in the lot.Since this is notpracticable,reliance is placed on the result obtained throughthe measurement of a sample.The likelihood that the observedaverage fiber diameter correctly identifies the grade increasesas the average approaches the midpoint of the fineness range ofthe gr