Standard Practice for Sampling Manufactured Staple Fibers, Sliver, or Tow for Testing

SIGNIFICANCE AND USE
Assigning a value to any property of the material in a container or in a lot, consignment, or delivery involves a measurement process that includes both sampling and testing procedures. The correctness of the value assigned depends upon the variability due to testing. Even when the variability due to testing is minimized by carefully developed procedures, correct and consistent estimates of the true value of the property are possible only when the sampling procedure avoids systematic bias, minimizes variations due to sampling, and provides a laboratory sample of adequate size.
This practice may not give the most efficient sampling plan that might be devised in special situations but it does present a general procedure that gives satisfactory precision with an economical amount of sampling and one which does not require elaborate statistical computation based on previous knowledge of the amount of variation between lot samples, between laboratory samples, and between test specimens.
The smallest number of specimens required for a given variability in the average result will usually be obtained by (1) minimizing the number of shipping units in the lot sample, (2) taking one of the shipping units in the laboratory sample, and (3) taking the prescribed specimen(s) from the selected laboratory sample shipping unit. (See 7.3 and 7.4.)
To minimize the cost of sampling a lot of material, it is necessary to agree on the required variance for the reported average for a lot of material:
Estimate the variance due to lot samples, the variance due to laboratory samples, and the variance due to test specimens.
Calculate the total variance for the average test results for several combinations of the number of lot samples, the number of laboratory samples per lot sample, and the number of test specimens per laboratory sample.
Calculate the cost of performing each of the sampling schemes considered in 5.4.2.
Select the sampling scheme that (1) has the required precision...
SCOPE
1.1 This practice covers a procedure for the division of shipments of manufactured staple fiber, sliver (or top) or tow into lots and the sampling of such lots for testing.
Note 1—For sampling yarns, refer to Practice D2258.
Note 2—This practice differs from BISFA rules for staple fibers in the lot sampling, by the elimination of separate sampling of outer versus inner container areas, in the reduction of number of strata from 6 to 5, and by the elimination of compositing to obtain a single laboratory sample for the lot when testing properties which do not depend on as-received moisture content.  
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

Status
Historical
Publication Date
30-Jun-2012
Technical Committee
Drafting Committee
Current Stage
Ref Project

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ASTM D3333-07(2012) - Standard Practice for Sampling Manufactured Staple Fibers, Sliver, or Tow for Testing
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D3333 − 07 (Reapproved 2012)
Standard Practice for
Sampling Manufactured Staple Fibers, Sliver, or Tow for
Testing
This standard is issued under the fixed designation D3333; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3.2 For all other terminology related to textiles, refer to
Terminology D123.
1.1 This practice covers a procedure for the division of
shipments of manufactured staple fiber, sliver (or top) or tow
4. Summary of Practice
into lots and the sampling of such lots for testing.
4.1 Instructions are given for dividing containers into lots,
NOTE 1—For sampling yarns, refer to Practice D2258.
for determining the number of containers to be selected from
NOTE 2—This practice differs from BISFA rules for staple fibers in the
each lot as the lot sample, and for determining the number of
lot sampling, by the elimination of separate sampling of outer versus inner
container areas, in the reduction of number of strata from 6 to 5, and by containers taken from the lot sample as a laboratory sample.
the elimination of compositing to obtain a single laboratory sample for the
See Practice D4271.
lot when testing properties which do not depend on as-received moisture
4.2 Separate laboratory samples are taken for commercial
content.
weight measurement and for other testing, for example, physi-
1.2 This standard does not purport to address all of the
cal or chemical tests.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
4.3 The manner of preparing laboratory sampling units for
priate safety and health practices and determine the applica- commercial weight, and the manner of collecting laboratory
bility of regulatory limitations prior to use.
sampling units for other testing are based on the following:
4.3.1 Present knowledge of the systematic variation of
2. Referenced Documents
moisture within the container, and
4.3.2 The variability of the properties for which the practice
2.1 ASTM Standards:
is to be used.
D123 Terminology Relating to Textiles
D2258 Practice for Sampling Yarn for Testing
5. Significance and Use
D4271 Practice for Writing Statements on Sampling in Test
Methods for Textiles (Withdrawn 2009)
5.1 Assigning a value to any property of the material in a
D4849 Terminology Related to Yarns and Fibers
container or in a lot, consignment, or delivery involves a
measurement process that includes both sampling and testing
3. Terminology
procedures. The correctness of the value assigned depends
upon the variability due to testing. Even when the variability
3.1 For all terminology relating to D13.58, Yarns and
due to testing is minimized by carefully developed procedures,
Fibers, refer to Terminology D4849.
correct and consistent estimates of the true value of the
propertyarepossibleonlywhenthesamplingprocedureavoids
ThispracticeisunderthejurisdictionofASTMCommitteeD13onTextilesand
systematic bias, minimizes variations due to sampling, and
is the direct responsibility of Subcommittee D13.58 on Yarns and Fibers.
provides a laboratory sample of adequate size.
Current edition approved July 1, 2012. Published August 2012. Originally
approved in 1974. Last previous edition approved in 2007 as D3333 – 07. DOI:
5.2 This practice may not give the most efficient sampling
10.1520/D3333-07R12.
plan that might be devised in special situations but it does
BISFA Internationally Agreed Methods for Testing Polyamide Staple Fibers,
present a general procedure that gives satisfactory precision
1974 edition, BISFA Internationally Agreed Methods for Testing Polyester Staple
with an economical amount of sampling and one which does
Fibers, 1972 edition, and BISFA Rules for Testing Regenerated Cellulose and
Acetate Staple Fibers, 1970 edition, available from the Bureau International pour la
not require elaborate statistical computation based on previous
Standardisation de la Rayonne et des Fibres Synthetiques.
knowledge of the amount of variation between lot samples,
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
between laboratory samples, and between test specimens.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
5.3 The smallest number of specimens required for a given
the ASTM website.
variability in the average result will usually be obtained by (1)
The last approved version of this historical standard is referenced on
www.astm.org. minimizing the number of shipping units in the lot sample, (2)
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D3333 − 07 (2012)
taking one of the shipping units in the laboratory sample, and random numbers. As applicable, consider containers to be the
(3) taking the prescribed specimen(s) from the selected labo- primarysamplingunit.Takethenumberofcontainersspecified
ratory sample shipping unit. (See 7.3 and 7.4.) in Table 1.
5.4 To minimize the cost of sampling a lot of material, it is 7.3 Laboratory Samples for Moisture Related Properties—
For acceptance testing, unless otherwise agreed upon, as when
necessary to agree on the required variance for the reported
average for a lot of material: specified in an applicable material specification, proceed as
directed in 7.3.1, 7.3.2,or 7.3.3. Samples for measurement of
5.4.1 Estimate the variance due to lot samples, the variance
moisture related properties cannot be used for measurement of
due to laboratory samples, and the variance due to test
other properties.
specimens.
7.3.1 Staple Fiber—Immediately upon opening each con-
5.4.2 Calculate the total variance for the average test results
tainer in the lot sample, prepare two laboratory samples as
for several combinations of the number of lot samples, the
follows:
number of laboratory samples per lot sample, and the number
7.3.1.1 Quickly strip off fiber down to each of the layers
of test specimens per laboratory sample.
illustrated in Fig. 1. As each layer is exposed, quickly collect
5.4.3 Calculate the cost of performing each of the sampling
an approximately 50-g hand sample in each hand, by picking
schemes considered in 5.4.2.
up small groups of fibers at points randomly distributed over
5.4.4 Select the sampling scheme that (1) has the required
the entire surface of the layer. Immediately put one of the hand
precision, and (2) is most economical to perform.
samples in one of the two tared laboratory sample containers
for the bale and the other hand sample in the second container.
6. Apparatus (for Moisture Related Properties)
Promptly close the containers. After all the layers have been
6.1 Sample Containers, tared to the nearest 0.1 g, formed of
sampled, the laboratory sample in each container should
impermeable materials, such as glass, polyethylene, or metal,
consist of about 250 g of fiber. It is essential to minimize fiber
and capable of being rapidly closed and sealed air-tight. The
exposure to the ambient atmosphere during each step of the
sample containers shall be of a size to contain approximately
preparation
...

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