ASTM D689-17(2024)

Standard Test Method for Internal Tearing Resistance of Paper

SIGNIFICANCE AND USE
4.1 This test method is widely used within the paper industry, in conjunction with other tests of strength, as a predictor of end-use performance of a wide range of grades of papers.
SCOPE
1.1 This test method measures the force perpendicular to the plane of the paper required to tear multiple sheets of paper through a specified distance after the tear has been started, using an Elmendorf-type tearing tester. The measured results can be used to calculate the approximate tearing resistance of a single sheet. In the case of tearing a single sheet of paper, the tearing resistance is measured directly.
Note 1: Similar procedures for making Elmendorf-type tear measurements are found in ISO 1974 and TAPPI T414.  
1.2 This test method is not suitable for determining the cross-directional tearing resistance of highly directional boards and papers.  
1.3 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 29-Feb-2024
• ICS: 85.060 - Paper and board
• Technical Committee: D09 - Electrical and Electronic Insulating Materials
• Drafting Committee: D09.01 - Electrical Insulating Products

Relations

• Replaces: ASTM D689-17 - Standard Test Method for Internal Tearing Resistance of Paper
• Effective Date: 01-Mar-2024
• Referred By: ASTM D1922-23 - Standard Test Method for Propagation Tear Resistance of Plastic Film and Thin Sheeting by Pendulum Method
• Effective Date: 01-Mar-2024
• Referred By: ASTM D619-21 - Standard Test Methods for Vulcanized Fibre Used for Electrical Insulation
• Effective Date: 01-Mar-2024
• Referred By: ASTM D202-23 - Standard Test Methods for Sampling and Testing Untreated Paper Used for Electrical Insulation
• Effective Date: 01-Mar-2024

Overview

ASTM D689-17(2024) - Standard Test Method for Internal Tearing Resistance of Paper sets out procedures for measuring the force required to tear multiple sheets of paper through a specified distance, using an Elmendorf-type tearing tester. This standard is widely adopted in the paper industry as a predictor of end-use performance for various grades of paper. By assessing internal tearing resistance, manufacturers and quality control professionals can better ensure paper durability and suitability for key applications.

The method is suitable for most papers but may not be accurate for highly directional papers and boards, particularly for cross-directional resistance. This internationally recognized method follows principles outlined by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

Key Topics

• Purpose: Evaluates the force perpendicular to the plane of paper necessary to propagate a standardized tear, assessing the internal strength of paper products.
• Equipment: Uses an Elmendorf-type tearing tester, available in mechanical or automated digital models, with standardized specimen dimensions.
• Sample Preparation: Typically involves tearing multiple sheets together, with results adjusted to report resistance per single ply. Consistent specimen orientation and preparation are essential for reproducibility.
• Notable Exclusions: Not valid for highly directional boards and cross-directional tearing resistance.
• Calibration and Adjustment: The tester must be properly calibrated and maintained, with regular scale verification and adjustment using check weights and other manufacturer-specified procedures.
• Result Reporting: Results are expressed as the average force required to tear a single sheet of paper, in either grams-force or millinewtons. Additional indices, such as tear index (normalized by grammage) can also be reported if required.
• Significance: Often combined with other strength tests to predict product performance and ensure compliance with customer and regulatory standards.

Applications

The ASTM D689 test method provides valuable data for a range of practical uses in the paper and packaging industries:

• Quality Assurance: Ensures paper products meet strength specifications before they reach customers.
• Product Development: Assists R&D teams in selecting materials and optimizing formulations for enhanced tear resistance.
• Comparative Analysis: Facilitates comparison among different paper grades, production batches, or supplier materials to ensure consistency and performance.
• Regulatory Compliance: Supports compliance for domestic and international paper sales, as the method aligns with ISO and TAPPI standards and WTO requirements.
• End-Use Performance Prediction: Helps determine the suitability of paper products for applications such as printing, packaging, stationery, and publishing, where minimum tearing resistance is crucial.

Related Standards

Several internationally recognized standards reference or are similar to ASTM D689, ensuring harmonized testing protocols within the industry:

• ISO 1974: Paper - Determination of tearing resistance (Elmendorf method)
• TAPPI T414: Internal Tearing Resistance of Paper
• ASTM D685: Practice for Conditioning Paper and Paper Products for Testing
• ASTM D646: Test Method for Mass Per Unit Area of Paper and Paperboard

Conclusion

Following ASTM D689-17(2024) ensures reliable, reproducible measurement of paper’s internal tearing resistance across a broad range of paper grades. Its adoption enhances quality control, supports research and development, and facilitates compliance with both customer requirements and international regulations, making it an essential standard for anyone involved in paper manufacturing, converting, or testing.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D689 − 17 (Reapproved 2024)
Standard Test Method for
Internal Tearing Resistance of Paper
This standard is issued under the fixed designation D689; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope D685 Practice for Conditioning Paper and Paper Products
for Testing
1.1 This test method measures the force perpendicular to the
D1749 Practice for Interlaboratory Evaluation of Test Meth-
plane of the paper required to tear multiple sheets of paper
ods Used with Paper and Paper Products (Withdrawn
through a specified distance after the tear has been started,
2010)
using an Elmendorf-type tearing tester. The measured results
E178 Practice for Dealing With Outlying Observations
can be used to calculate the approximate tearing resistance of
2.2 ISO Standard:
a single sheet. In the case of tearing a single sheet of paper, the
ISO 1974 Paper—Determination of Tearing Resistance (El-
tearing resistance is measured directly.
mendorf method)
NOTE 1—Similar procedures for making Elmendorf-type tear measure- 5
2.3 TAPPI Standard:
ments are found in ISO 1974 and TAPPI T414.
TAPPI T414 Internal Tearing Resistance of Paper
1.2 This test method is not suitable for determining the
cross-directional tearing resistance of highly directional boards
3. Summary of Test Method
and papers.
3.1 One or more sheets of the sample material are torn
1.3 This standard does not purport to address all of the
together through a fixed distance by means of the pendulum of
safety concerns, if any, associated with its use. It is the
an Elmendorf-type tearing tester. The work done in tearing is
responsibility of the user of this standard to establish appro-
measured by the loss in potential energy of the pendulum. The
priate safety, health, and environmental practices and deter-
instrument scale is calibrated to indicate the average force
mine the applicability of regulatory limitations prior to use.
exerted when a certain number of plies are torn together (work
1.4 This international standard was developed in accor-
done divided by the total distance torn).
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
4. Significance and Use
Development of International Standards, Guides and Recom-
4.1 This test method is widely used within the paper
mendations issued by the World Trade Organization Technical
industry, in conjunction with other tests of strength, as a
Barriers to Trade (TBT) Committee.
predictor of end-use performance of a wide range of grades of
papers.
2. Referenced Documents
2.1 ASTM Standards:
5. Apparatus
D646 Test Method for Mass Per Unit Area of Paper and
5.1 Elmendorf-type Tearing Tester—Several types are avail-
Paperboard of Aramid Papers (Basis Weight) (Withdrawn
able and in use throughout the world, principally those of
2022)
Australian, British, German, Swedish, and United States manu-
facture. In addition, testing practices also vary.
This test method is under the jurisdiction of ASTM Committee D09 on
5.2 Instrumental and Procedural Variables—Instruments
Electrical and Electronic Insulating Materials and is the direct responsibility of
and practices in use vary in at least two major respects:
Subcommittee D09.01 on Electrical Insulating Products.
Current edition approved March 1, 2024. Published March 2024. Originally
5.2.1 The Design of the Specimen Clamps—Together with
created by ASTM Committee D06.92 Paper and Paper Products and approved in
the structural characteristics of the paper governing the nature
1942. Last previous edition approved in 2017 as D689 – 17. DOI: 10.1520/D0689-
of the tear with respect to its splitting tendencies during the
17R24.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on Available from American National Standards Institute, 25 W. 43rd St., 4th
the ASTM website. Floor, New York, NY 10036.
3 5
The last approved version of this historical standard is referenced on Available from the Technical Association of the Pulp and Paper Industrial, P.O.
www.astm.org. Box 105113, Atlanta, GA 30348.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D689 − 17 (2024)
test, this has an appreciable influence on the mode of tearing
and can result in significant differences (1) . The procedure
described in 5.3.7 reduces this effect. The clamp designs used
by some manufacturers can vary even for their own models.
Instruments are available with pneumatically activated grips as
well, which minimizes variations due to differences in clamp-
ing pressures exerted by manually tightened grips.
5.2.2 A Combined Variation in Testers and Testing
Practices—As measured tearing resistance increases or de-
creases for different types of paper, the measurement can
become so large or so small as to be outside the practical range
of the instrument. This problem can be overcome in one of two
ways; change the number of sample sheets tested at one time to
be changed, or the mass of the instrument pendulum can be
changed either by adding augmenting weights or by replacing
the entire pendulum with one of a different known mass. The
tearing length must never be varied in an effort to alter the
pendulum capacity.
5.2.3 These differences, together with other lesser differ-
ences in design details between instruments or testing
practices, preclude specifying a tearing instrument and method
that would give essentially the same test results when using
Elmendorf instruments of different design and manufacture.
Even for one specific model, some procedural variables such as
the number of plies torn can alter the test values calculated on
a single sheet basis substantially. By necessity, this reference
method must be arbitrary and is limited to the described
procedure used with instruments conforming to all of the
FIG. 1 Newer Testing Model with Deep Cutout
requirements specified under 5.3.
5.3 Required Instrument for this Test Method:
5.3.1 Elmendorf Tearing Tester (2, 3, 4), with a cutout as
plane parallel to the axis of the pendulum, the plane making an
shown in Fig. 1, which prevents the specimen from coming in
angle of 27.5 6 0.5° with the perpendicular line joining the
contact with the pendulum sector during the test, and having
axis and the horizontal line formed by the top edges of the
the following elements:
clamping jaws. The distance between the axis and the top edges
5.3.2 Stationary and Movable Clamp—The movable clamp
of the clamping jaws is 103.0 6 0.1 mm. The clamping surface
is carried on a pendulum formed by a sector of a circle free to
in each jaw is at least 25 mm wide and 15.9 6 0.1 mm deep.
swing on a ball bearing.
5.3.3 Knife, mounted on a stationary post for starting the
NOTE 2—In the past, it has been the practice for instruments commonly
tear. available in the United States to be equipped with 36 6 1 mm wide jaws.
It is possible for instruments currently available to be equipped with jaws
5.3.4 Means for Leveling the Instrument.
as narrow as 25 mm. Testing has shown that the effect of jaw width on test
5.3.5 Pendulum Holder—Means for holding the pendulum
results is statistically insignificant. It is recommended, however, that the
in a raised position and for releasing it instantaneously.
test specimen length be adjusted to match jaw width. See Note 3.
5.3.6 Means for Registering the Maximum Arc through
5.3.8 The instrument measures the energy (work done) used
which the pendulum swings when released. The registering
by the pendulum in tearing the test specimen. In order to
means can consist of a graduated scale mounted on the
convert to average tearing force, the energy must be divided by
pendulum, a pointer mounted on the same axis as the pendulum
the total distance through which the force is applied. This
with constant friction just sufficient to stop the pointer at the
division can be accomplished by the electronics in digital
highest point reached by the swing of the sector, and an
readout instruments so that the readout is directly in grams-
adjustable pointer stop for setting the zero of the instrument.
force or in millinewtons (SI unit of force). For pointer and
5.3.6.1 The pointer and scale can be replaced by a digital
scale instruments, the scale could be in millinewtons or in
readout unit which gives readings of equivalent accuracy and
grams-force for a specified number of plies; for example, when
precision (5).
the specified number of plies are torn together, the scale
5.3.7 With the pendulum in its initial position ready for a
reading gives the average tearing resistance (force) of a single
test, the clamps are separated by an interval of 2.8 6 0.3 mm
ply.
and are so aligned that the specimen clamped in them lies in a
5.3.9 Instruments of several capacities (2000, 4000, 8000,
16 000 32 000 mN (200, 400, 800, 1600, 3200 gf)) and perhaps
others are available, with the several capacities being achieved
The boldface numbers in parentheses refer to the list of references at the end of
this standard. by individual instruments, interchangeable pendulum sectors,
D689 − 17 (2024)
or augmenting weights. The instrument recognized as “stan- dimension through which the tear will be propagated is 63.0 6
dard” for this test method has a capacity of 1600 gf (15.7 N), 0.15 mm. Take all the plies to be torn together from a single
having a pendulum sector of such mass and mass distribution sheet. If sufficient material is not provided, take from adjacent
that its 0 to 100 scale is direct reading in grams-force per ply sheets of a unit.
when 16 plies are torn together. For a 16-ply test specimen, the
NOTE 4—The correct dimension for the side of the test specimen that
will be placed in the clamps is equal to the distance between the outermost
tearing distance K = 16 × 4.3 cm (tearing distance per ply) × 2
edges of each of the instrument’s jaws (62 mm). For the instrument
= 137.6 cm. The factor 2 is included since in tearing a given
described in 5.3, that distance is at least 2 × 25 mm (the minimum width
length the force is applied twice the distance. Likewise, for a
for each jaw face) plus 2.8 mm (the distance between the clamps) or at
16-ply test specimen, the tearing energy per ply for a scale
least 53 mm. In the United States, the majority of the instruments have
reading of 100 would then be 100 gf × 137.6 cm or 13 760
jaws 36 + 1 mm wide. A dimension of 76 6 2.0 mm for the side of the
gf·cm (1349.4 mJ). For some of the instruments of different sample to be held in the clamps is correct.
capacities where different numbers of plies are required, or
7. Calibration and Adjustment
when the number of plies tested using the “standard” instru-
ment differs from 16, different values of K or the tearing energy
7.1 As noted in Section 5, several Elmendorf-type testers
per ply, or both, can be calculated.
are available and in use at the present time. Minor differences
5.3.10 n the “standard” instrument, the zero reading on the
in calibration or adjustment procedures, or both, can apply to
scale is at about 70° from the center line (that is, the vertical
instruments obtained from different vendors that comply with
balance line when the pendulum hangs freely), the 100 reading
5.3, thus it is questionable that specific calibration procedures
is at about 21° from the center line, and a vertical force of
can be used for all instruments complying with 5.3. The
1057.3 6 2.0 gf (10.369 6 0.020 N) applied at 22.000 6
information contained in this section is to be used as a guide in
0.005 cm from the pendulum axis is required to hold the
placing an individual instrument into proper calibration for use
pendulum sector at 90° from its freely hanging position. Other
in performing the test.
tearing instruments will require vertical forces that are factors
of 2 greater or smaller than 1057.3 gf and, if calibrated in
7.2 Verification of Scale—Once the scale has been verified,
millinewtons, the zero reading would remain at 70° and the it is unnecessary to repeat this step, provided the tester is kept
1000 reading would be at about 19° (or the 981 reading at
in adjustment and no parts become changed or perceptibly
about 21°).
worn. The scale can be verified either by the potential energy
5.3.11 The cutting knife for the test specimen is centered
method or by the method which uses the check weights
between the clamps and adjusted in height so that the tearing
obtainable from the manufacturer. The potential energy method
distance is 43.0 6 0.2 mm; for example, the distance between
is relatively time-consuming and complicated. The check
the end of the slit made by the knife and the upper edge of the
weight method is relatively simple.
specimen is 43.0 6 0.2 mm when the lower edge of the
7.2.1 Potential Energy Method—The procedure (7) for veri-
63.0 mm wide specimen rests against the bottom of the clamp.
fication is as follows: Anchor and level the tester. Clamp a
known weight (in grams), W, to the radial edge of the sector
5.4 Instruments are available for automated testing that
beneath the jaws, the center of gravity of the weight (including
incorporates automatic sample insertion, automatic sample
means of attaching) having been previously marked by a
cutting, and so forth, in addition to electronic data readout as
punched dot on the face of the weight that is to be toward the
specified in 5.3.4. These automated instruments can be used,
front of the instrument. Close the jaw of the clamp in the sector.
provided the conditions specified in 5.3 are met.
Raise and set the sector as for tearing a sheet and, by means of
5.5 Specimen Cutter, to ensure parallel specimens 63 6
a surface gauge or cathetometer, measure in centimetres, to the
0.15 mm wide with sharp and clean edges. For this purpose, it
nearest 0.01 cm, the height, H, of the center of gravity of the
is desirable to use the type having two hardened and ground
weight above a fixed horizontal surface. Then release the
base shears, twin knives tensioned against the base shears, and
sector, allow it to swing and note the pointer reading. Without
a hold-down mechanism.
touching the pointer, raise the sector until the edge of the
6. Sampling and Test Specimens pointer just meets with its stop, in which position again
determines the height, h, of the center of gravity of the weight
6.1 Obtain the sample to be tested in accordance with
above the fixed surface.
Methods D585.
7.2.2 Use the following formula for the standard 1600-gf
6.2 From each test unit of the sample, prepare ten represen-
tester:
tative specimens in each principal direction of the paper, unless
W~h 2 H! in gf 2 cm (1)
a test in only one direction is required. For each specimen,
arbitrarily designate one side of the material in some way, such
where:
as “primary side”, “print side”, “wire side”, “side one”, and so
W(h-H)/K = the pointer reading, and
forth. For each specimen, keep the designated sides of all the
K = 137.6 cm.
plies facing the same way.
NOTE 3—It has been found (6) that there is usually no advantage in
For other instruments graduated for grams-force of greater or
testing more than ten specimens of a homogeneous test unit of the sample.
lesser capacity, the reading will be factors of 2 greater or
6.3 Cut each ply for a test specimen so that its dimension on smaller. If graduated for millinewtons, the additional factor
the side placed in the clamps is at least 53 mm and the 9.81 must be applied.
D689 − 17 (2024)
7.2.2.1 It is permissible for one or more weights to be table or instrument during the swing of the pendulum. It is
clamped on the edge of the sector for each calibration point. possible that any movement of the instrument base during the
The work done in raising each weight is c
...