ASTM D5362-97a
(Test Method)Standard Test Method for Snagging Resistance of Fabrics (Bean Bag Test Method)
Standard Test Method for Snagging Resistance of Fabrics (Bean Bag Test Method)
SCOPE
1.1 This test method determines the snagging resistance of a fabric.
1.2 Studies of fabric snagging have shown that this test method is suitable for a range of woven and knitted fabrics made from textured or untextured yarns containing staple or continuous filaments. This test method is not suitable for (1) open construction fabrics (such as a net) because the pins in the test chamber will snag the bean bag rather than the specimen, (2) heavy or stiff fabrics that cannot be made into a cover for the bean bag, and (3) tufted or nonwoven fabrics because the apparatus is designed for woven and knitted fabrics.
1.3 The values stated in either acceptable metric units or in other units shall be regarded separately as standard. The values stated in each system may not be the exact equivalents; therefore, each system must be used independently of the other, without combining values in any way. In case of referee decisions the metric units will prevail.
1.4 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. Specific precautionary statements are given in section 7.
General Information
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Standards Content (Sample)
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
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Designation: D 5362 – 97a
Standard Test Method for
Snagging Resistance of Fabrics (Bean Bag)
This standard is issued under the fixed designation D 5362; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope and Leather Products Other Than Textile Floor Coverings
and Upholstery
1.1 This test method determines the snagging resistance of a
D 3939 Test Method for Snagging Resistance of Fabrics
fabric.
(Mace)
1.2 Studies of fabric snagging have shown that this test
D 4467 Practice for Interlaboratory Testing of a Textile Test
method is suitable for a range of woven and knitted fabrics
Method That Produces Non-Normally Distributed Data
made from textured or untextured filament yarns or spun yarns
2,3
2.2 AATCC Standards:
or combinations of these yarns. This test method is not
65 Test Method for Snag Resistance of Women’s Nylon
suitable for (1) open construction fabrics (such as a net)
Hosiery (see Note 1)
because the pins in the test chamber will snag the bean bag
135 Test Method for Dimensional Changes in Automatic
rather than the specimen, (2) heavy or stiff fabrics that cannot
Home Laundering of Woven and Knit Fabrics
be made into a cover for the bean bag, and (3) tufted or
nonwoven fabrics because the apparatus is designed for woven
NOTE 1—In 1988 the AATCC voted to withdraw this test method from
and knitted fabrics. their technical manual; however, the ASTM task group on fabric snagging
decided it should be listed as an alternative for testing open construction
1.3 The values stated in either acceptable metric units or in
fabrics.
other units shall be regarded separately as standard. The values
stated in each system may not be the exact equivalents;
3. Terminology
therefore, each system must be used independently of the other,
3.1 Definitions:
without combining values in any way. In case of referee
3.1.1 color contrast, n—in textiles, a general term for a
decisions the metric units will prevail.
visible color difference between two adjacent areas.
1.4 This standard does not purport to address all of the
3.1.1.1 Discussion—For the purpose of this test method, a
safety concerns, if any, associated with its use. It is the
color contrast is a visible color difference between a snag and
responsibility of the user of this standard to establish appro-
the immediate surrounding area of the fabric that has no
priate safety and health practices and determine the applica-
defects. Color contrasts often occur when printed fabrics are
bility of regulatory limitations prior to use. Specific precau-
snagged.
tionary statements are given in Section 7.
3.1.2 distortion, n—in fabrics, a general term for a visible
2. Referenced Documents defect in the texture of a fabric.
3.1.2.1 Discussion—For the purpose of this test method,
2.1 ASTM Standards:
snags are composed of different combinations of protrusions
D 123 Terminology Relating to Textiles
4 and distortions. A distortion is characterized by a group of
D 1335 Test Method for Tuft Bind of Pile Floor Coverings
fibers, a yarn, or a yarn segment that is displaced from its
D 1776 Practice for Conditioning Textiles for Testing
normal pattern so that there is a visible change in the texture of
D 2724 Test Methods for Bonded, Fused, and Laminated
the fabric; however, the displaced group of fibers, yarn, or yarn
Apparel Fabrics
segment does not extend above the fabric surface. Distortions
D 3136 Terminology Relating to Care Labels for Textile
include conditions where (1) tension on a snagged yarn has
changed the size of some of the loops within a knitted fabric
and the result is a pucker on the surface of the fabric, and (2)
This test method is under the jurisdiction of ASTM Committee D-13 on Textiles tension on a snagged yarn has caused the yarn to break off
and is the direct responsibility of Subcommittee D13.59 on Fabric Test Methods,
within a woven fabric and the result is a change in the texture
General.
where the yarn used to be.
Current edition approved Dec. 10, 1997. Published August 1998. Originally
3.1.3 protrusion, n—in fabrics, a general term for a visible
published as D 5362 – 93. Last previous edition D 5362 – 97.
Stuckey, W. C., and El Shiekh, A., “Snags in Snag Testing of Knits”, in Sense
and Nonsense in Knit Testing, American Association of Textile Chemists and
Colorists, 1975, pp. 45–53.
Cary, R. T., “Bean Bag Snag Tester: A System of Evaluation”, Textile Research
Annual Book of ASTM Standards, Vol 07.02.
Journal, Vol 51, No. 2, 1981, pp. 61–63.
Available from American Association of Textile Chemists and Colorists, P.O.
Annual Book of ASTM Standards, Vol 07.01.
Box 12215, Research Triangle Park, NC 27709.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 5362
group of fibers, a yarn, or a yarn segment that extends above slacks, and upholstery).
the fabric surface.
5.3.1 For a specific fabric, if the test results from this test
3.1.4 snag, n—in fabrics, a yarn or part of a yarn pulled or
method do not correspond with the test results from a wear test
plucked from the surface.
then (1) the procedure described in Section 12 or (2) the
3.1.4.1 Discussion—For the purpose of this test method, a
evaluation described in Section 13 can be modified. For
snag is created when an object pulls, plucks, scratches, or drags
example, the number of revolutions of the test chamber for
a group of fibers, a yarn, or a yarn segment from its normal
testing each specimen can be increased for a fabric that had a
pattern. Snags can be classified into three types: (1) snags that
higher degree of snagging in a wear test than the same fabric
have a protrusion and no distortion, (2) snags that have a
had using the procedure described in Section 12. The purchaser
distortion and no protrusion, and (3) snags that have both a
and the supplier must agree to all changes in the procedure for
protrusion and a distortion. Other changes in appearance, such
operating the apparatus or for evaluating the test results.
as color contrasts, should be reported because they affect the
5.3.2 Some fabrics which may not be suitable for this test
visibility of a protrusion or a distortion.
method are described in 1.2. Many open construction fabrics
3.1.5 snagging resistance, n—in textile fabrics, the property
can be tested for snagging resistance using AATCC Test
of a material whereby yarns or parts of yarns are prevented or
Method 65. Many heavy or stiff fabrics can be tested for
inhibited from being pulled or plucked from the surface.
snagging resistance using Test Method D 3939. The snagging
3.1.6 For definitions of other textile terms used in this test
resistance of many pile floor coverings can be tested by Test
method, refer to Terminology D 123.
Method D 1335.
5.3.3 When the purchaser and the supplier agree that the test
4. Summary of Test Method
results from the bean bag test method do not correspond with
4.1 A fabric specimen is made into a cover for a bean bag.
the test results from a wear test, Test Method D 3939 can be
Then the specimen and bean bag unit is tumbled for 100
used.
revolutions in a cylindrical test chamber fitted on its inner
5.4 Because fabric snagging can be affected by laundering
surface with rows of pins. The degree of fabric snagging is
or drycleaning, it may be advisable to test the snagging
evaluated by (1) comparison of the tested specimens with
resistance of a fabric before and after laundering or dryclean-
visual rating standards that may be either snagged fabrics or
ing.
photographs of snagged fabrics, or (2) using a point system.
5.5 The snagging resistance of a specific fabric varies with
The resistance to snagging is rated on a numerical scale
individual wearers and general conditions of use. Therefore, it
ranging from 5 (no or insignificant snagging) to 1 (very severe
can be expected that garments of the same fabric will show a
snagging).
fairly wide snagging resistance spectrum after wear and much
5. Significance and Use
greater variation in wear than in replicate fabric specimens
subjected to controlled laboratory tests. This factor should be
5.1 Acceptance Testing—This test method may be used for
considered when adopting levels of acceptability for any
acceptance testing of commercial shipments of fabrics because
specification that includes snagging resistance.
the precision is acceptable (see 15.1).
5.1.1 In case there are disputable differences between re- 5.6 Snags observed in worn garments vary appreciably in
ported test results for two laboratories (or more), comparative number and appearance. The appearance of a snag depends
tests should be performed to determine if there is a statistical particularly on (1) the degree of color contrast between the
bias between them, using competent statistical assistance. As a snag and the surrounding area of the fabric, or, (2) the
minimum, specimens should be used that are as homogeneous presence of long distortions or long protrusions. These condi-
as possible, that are drawn from the material from which tions are not evaluated when snagging is rated solely on the
disputable test results were obtained, and that are randomly number of snags. See Section 3 for a description of terminol-
assigned in equal numbers to each laboratory for testing. The ogy such as color contrast, distortion, and protrusion. See Figs.
test results from the two laboratories should be compared using 1-3 for pictures of fabric defects due to snagging. Because the
an appropriate statistical test for unpaired data, at a probability overall acceptability of a specific fabric is dependent on both
level chosen prior to the testing series. If a bias is found, either the characteristics of the snags and other factors affecting
its cause must be found and corrected, or future test results fabric appearance, it is recommended that fabrics tested in the
must be adjusted in consideration of the known bias. laboratory be evaluated with regard to the defects which may
5.2 This test method may be used for quality control testing be visually observed and not rated solely on the number of
of fabrics during manufacturing and product comparisons of snags developed. A series of visual rating standards (see 6.7)
may be set up to provide a basis for the ratings. The visual
different fabrics by manufacturers, retailers, and users. This test
method may also be used by researchers to examine the effect rating standards are most advantageous when the tested labo-
of new fibers, yarns, fabric constructions, and finishes on the ratory specimens correlate closely in appearance with fabrics
snagging resistance of fabrics. from a wear test; for example when tested laboratory speci-
5.3 This test method may be used to test the snagging mens and fabrics from a wear test show similar color contrasts.
resistance of most apparel and home furnishings fabrics. In the preceding example, a series of fabrics from the wear test
Modifications of this test method (see 5.3.1), or a different test would be a good choice for the fabric standards described in
method (see 5.3.2 and 5.3.3), may be needed for different types 6.7.2. Also a point rating system may be used that considers the
of fabrics and different end-uses (such as towels, swimwear, number of the snags and the appearance of the snags (see 13.3).
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 5362
FIG. 1 A Snagged Specimen With Many Protrusion But No
FIG. 3 A Snagged Specimen With Color Contrasts (Yarn Shifted
Distortions
from Dark Area to Light Area
FIG. 4 The Bean Bag Snag Tester With Two Test Chambers
FIG. 2 A Snag That Includes Both a Protrusion and a Distortion
6.1.1 Bean Bags , filled with shot and each weighing 450 6
10gor1.0 6 0.02 lb. A minimum of two bean bags is required,
6. Apparatus and Materials
but six bean bags are suggested for efficiency.
6.1 Bean Bag Snag Tester , as shown in Fig. 4. Each
6.2 Specimen Template, made of approximately 2 mm or 0.1
rotating cylinder (2.1 6 0.3 rad/s or 20 6 3 r/min) is fitted with
in. thick poster board, plastic or metal with dimensions of 215
a snagging basket which is a removable framework of eight
mm by 115 mm or 8.5 in. by 4.5 in.
baffle bars attached at each end to plastic disks. Each baffle bar
6.3 Sewing Machine, with a sewing needle that is appropri-
has a series of nine pins protruding from it. Each baffle bar is
ate for the fabric being tested for snagging resistance, or
locked in the plastic disks so that when a baffle bar is exactly
6.4 Sharps Hand Sewing Needle.
at the bottom of the cylinder, an angle of 0.5 6 0.1 rad or 30
6.5 Sewing Thread, cotton, Tex ticket 35 to 50, or equivalent
6 5° exists between the pins on that baffle bar and a theoretical
polyester and cotton.
horizontal line passing through the end of the baffle bar.
6.6 Standard Calibration Fabric, having an established
snagging resistance rating that has been agreed upon by the
purchaser and the supplier. (No standard calibration fabric has
The sole source of supply of the apparatus known to the committee at this time
been specified by Subcommittee D13.59.)
is (Atlas Electric Devices Co., 4114 N. Ravenswood Ave., Chicago, IL 60613). If
6.7 Visual Rating Standards (for Option A):
you are aware of alternative suppliers, please provide this information to ASTM
6.7.1 Photographic Standards, a series of photographs of
Headquarters. Your comments will receive careful consideration at a meeting of the
responsible technical committee. tested specimens that show the degrees of snagging, such as the
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 5362
Imperial Chemical Industries (ICI) photographs, or 6.8.1.2 Specimen Viewing Mask (White), made of approxi-
6.7.2 Fabric Standards, a series of tested specimens or mately 2 mm or 0.1 in. thick poster board, plastic or metal with
fabrics from a wear test that show the degrees of snagging (see outer dimensions of 100 mm by 100 mm or 4 in. by 4 in. and
5.6 and Note 2). a center cutout of 75 mm by 75 mm or 3 in. by 3 in.
6.8.1.3 Photogr
...
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