ASTM D1042-22

• Abstract:

  SIGNIFICANCE AND USE; 4.1 This test method is intended only as a convenient test method for measurement of linear dimensional changes in plastics subjected to defined conditions of test as outlined in Sections 7 and 8.; SCOPE; 1.1 This test method is designed to provide a means for measuring the dimensional changes of plastic specimens such as shrinkage or expansion, developed under specific heat and water conditionings. ; 1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard. ; 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. ; Note 1: This standard and ISO 2796 address the same subject matter but differ in technical content. ; 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.

• Status: Published
• Publication Date: 30-Apr-2022
• ICS: 83.080.01 - Plastics in general
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.50 - Durability of Plastics

• Refers: ASTM D883-24 - Standard Terminology Relating to Plastics
• Effective Date: 01-Feb-2024
• Refers: ASTM D883-23 - Standard Terminology Relating to Plastics
• Effective Date: 01-Nov-2023
• Refers: ASTM E456-13a(2022)e1 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Apr-2022
• Refers: ASTM D883-20 - Standard Terminology Relating to Plastics
• Effective Date: 01-Jan-2020
• Refers: ASTM D883-19c - Standard Terminology Relating to Plastics
• Effective Date: 01-Aug-2019
• Refers: ASTM D883-19a - Standard Terminology Relating to Plastics
• Effective Date: 15-Apr-2019
• Refers: ASTM D883-19 - Standard Terminology Relating to Plastics
• Effective Date: 01-Feb-2019
• Refers: ASTM D883-18a - Standard Terminology Relating to Plastics
• Effective Date: 01-Dec-2018
• Refers: ASTM D883-18 - Standard Terminology Relating to Plastics
• Effective Date: 01-Nov-2018
• Refers: ASTM E456-13A(2017)e1 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Oct-2017
• Refers: ASTM E2935-17 - Standard Practice for Conducting Equivalence Testing in Laboratory Applications
• Effective Date: 01-Oct-2017
• Refers: ASTM E456-13A(2017)e3 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Oct-2017
• Refers: ASTM D883-17 - Standard Terminology Relating to Plastics
• Effective Date: 15-Aug-2017
• Refers: ASTM E2935-16 - Standard Practice for Conducting Equivalence Testing in Laboratory Applications
• Effective Date: 15-Nov-2016
• Refers: ASTM E2935-15 - Standard Practice for Conducting Equivalence Testing in Laboratory Applications
• Effective Date: 01-Oct-2015

Overview

ASTM D1042-22 is the internationally recognized standard test method for determining the linear dimensional changes in plastics when exposed to specified conditions of heat and moisture. Developed by ASTM International, this method offers a reliable framework for evaluating shrinkage or expansion in plastic specimens, supporting quality assurance and material development for industries using plastic materials.

This standard specifies procedures for preconditioning, conditioning, and testing plastic samples to provide quantitative data regarding dimensional stability-a critical performance attribute for plastics used in various applications. Values are stated in SI units as the recognized standard, with inch-pound conversions provided for reference.

Key Topics

• Dimensional Stability Assessment
  The method specifically measures linear shrinkage or expansion resulting from controlled exposure to moisture (via water immersion) and elevated temperatures (via oven conditioning).

• Specimen Preparation and Conditioning

  • Specimens are preconditioned at 23 ± 2°C and 50 ± 10% relative humidity.
  • Test methods include immersion in water at controlled temperature or oven exposure, simulating real-world service conditions.

• Measurement Procedure

  • Utilizes precise instrumentation such as a calibrated scriber, measuring microscope, and calipers to ensure accurate linear measurements to the nearest 0.01 mm.
  • Dimensional changes are reported as a percent change based on initial scribed length.

• Reporting Requirements

  • Detailed documentation including test conditions, equipment used, material identification, conditioning method, measurement approach, and calculated results is mandatory.

• Safety and Compliance

  • Users must establish appropriate safety, health, and environmental practices prior to use, ensuring regulatory compliance.

Applications

ASTM D1042-22 is widely applicable to manufacturers, material scientists, and quality assurance professionals seeking to characterize and verify the dimensional stability of plastic products. Key practical applications include:

• Material Selection and Design
  Assists engineers and designers in selecting appropriate plastics for products where dimensional precision is critical, such as automotive parts, electronic housings, and construction materials.

• Quality Control
  Enables manufacturers to maintain quality standards and assure customers of consistent product performance by identifying materials that meet stability requirements after exposure to heat and moisture.

• Research and Development
  Supports laboratories and R&D teams in benchmarking new plastic materials or formulations against industry standards, accelerating innovation cycles.

• Regulatory Documentation
  Provides validated testing methods for demonstrating compliance with technical specifications required by customers or regulatory bodies.

Related Standards

For comprehensive evaluation, users of ASTM D1042-22 may reference the following standards:

• ASTM D883 – Terminology Relating to Plastics: Defines terms used in plastic testing and characterization.
• ASTM D5947 – Test Methods for Physical Dimensions of Solid Plastics Specimens: Covers specimen measurement procedures.
• ASTM E456 – Terminology Relating to Quality and Statistics: Guides testing precision and bias analysis.
• ASTM E691 – Practice for Conducting Interlaboratory Studies: Provides methodology for assessing reproducibility and precision.
• ASTM E2935 – Practice for Evaluating Equivalence of Two Testing Processes.
• ISO 2796 – Cellular plastics, rigid-Test for dimensional stability: An international equivalent, though with different technical content.

Summary

ASTM D1042-22 establishes a consistent, precise approach for measuring the linear dimensional changes of plastics due to heat and moisture. By following this standard, organizations can ensure that their plastics maintain dimensional integrity under relevant service conditions, supporting high product quality and regulatory compliance. This standard is essential for anyone involved in the plastics supply chain, from raw material producers to end-product manufacturers.

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: D1042 − 22
Standard Test Method for
Linear Dimensional Changes of Plastics Caused by
Exposure to Heat and Moisture
This standard is issued under the fixed designation D1042; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* 2.2 ISO Standards:
ISO2796Cellular plastics, rigid—Test for dimensional sta-
1.1 This test method is designed to provide a means for
bility
measuring the dimensional changes of plastic specimens such
as shrinkage or expansion, developed under specific heat and
3. Terminology
water conditionings.
3.1 Definitions:
1.2 The values stated in SI units are to be regarded as
3.1.1 For definitions of terms that appear in this practice
standard. The values given in parentheses are mathematical
relating to plastics, refer to Terminology D883.
conversions to inch-pound units that are provided for informa-
3.1.2 For definitions of terms that appear in this practice
tion only and are not considered standard.
relating to quality and statistics (such as precision and bias),
1.3 This standard does not purport to address all of the
refer to Terminology E456.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
4. Significance and Use
priate safety, health, and environmental practices and deter-
4.1 This test method is intended only as a convenient test
mine the applicability of regulatory limitations prior to use.
method for measurement of linear dimensional changes in
NOTE 1—This standard and ISO 2796 address the same subject matter
plastics subjected to defined conditions of test as outlined in
but differ in technical content.
Sections 7 and 8.
1.4 This international standard was developed in accor-
dance with internationally recognized principles on standard-
5. Apparatus
ization established in the Decision on Principles for the
5.1 Scriber, so constructed that two sharp needle points are
Development of International Standards, Guides and Recom-
rigidly separated by 100 6 0.2 mm. The scriber, as shown in
mendations issued by the World Trade Organization Technical
Fig. 1, consists of two sharp steel needles, approximately 1.5
Barriers to Trade (TBT) Committee.
mm in diameter.The needles are to be inserted in drilled holes
2. Referenced Documents
with their axes parallel to each other and perpendicular to and
intersecting the long axis of a stainless steel rigid rod or bar
2.1 ASTM Standards:
stock, 125 6 5 mm in length. The needles’ points shall extend
D883Terminology Relating to Plastics
6 6 2 mm beyond the supporting rod and are held in position
D5947Test Methods for Physical Dimensions of Solid
by setscrews inserted through the ends of the rod. The scriber
Plastics Specimens
shall be calibrated by scribing an arc onto an unconditioned
E456Terminology Relating to Quality and Statistics
sample and measuring this initial scribed distance with a
E691Practice for Conducting an Interlaboratory Study to
calibrated caliper to the nearest 0.1 mm.Thickness of arc lines
Determine the Precision of a Test Method
shall not exceed 0.02 mm.
E2935Practice for Evaluating Equivalence of Two Testing
NOTE 2—Phonograph needles have been used as a satisfactory scriber.
Processes
5.2 Measuring Microscope, having a magnification of at
1 least 20× and graduated to have a resolution of 0.01 mm.
ThistestmethodisunderthejurisdictionofASTMCommitteeD20onPlastics
and is the direct responsibility of Subcommittee D20.50 on Durability of Plastics.
NOTE 3—For more precise measurements, a micrometer microscope is
Current edition approved May 1, 2022. Published May 2022. Originally
preferred.
approved in 1949. Last previous edition approved in 2017 as D1042–12(2017).
DOI: 10.1520/D1042-22.
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 fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
the ASTM website. 4th Floor, New York, NY 10036, http://www.ansi.org.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D1042 − 22
7.5 Conduct tests in a standard laboratory atmosphere of 23
6 2°C and 50 6 10 % relative humidity.
8. Procedure
8.1 Immediately following the preconditioning, scribe an
arcof100-mmradiusonthesurfaceofthetestspecimen.Press
one needle firmly into the specimen to form a center for this
FIG. 1 Scriber
andsubsequentmeasurements.Theotherneedlescribesthearc
thatisusedasareferenceforallsubsequentmeasurements(see
5.3 Caliper, 6-in., with a readability of 0.01 mm and an
Fig. 2). Draw the arcs smoothly, using a pressure consistent
illuminated desk magnifier, 1.75× to 2.0× to assist with the
with the surface hardness and test conditions to which the
placement of the caliper points onto the scribed lines
specimen is subjected. It is desirable to lightly scratch the
5.4 Beaker, having a suitable size for the number of speci-
surface with the needle so that a sharp, clear arc is defined.
mens to be evaluated and is constructed of a material that is
stable under the test conditions.
5.5 Room or Conditioning Chamber,capableofbeingmain-
tained at 23 6 2°C and 50 6 10 % RH.
5.6 Conditioning Oven, full draft air-circulating oven, ca-
pable of being maintained within 62°C of the set temperature.
5.7 Absorbent Material, cloth or paper suitable for drying.
6. Test Specimens
6.1 Specimensshallnotbelessthan110mminlengthinthe
direction of test. The preferred specimen size is 125 65mm
1—Original arc
in length by 13 6 0.5 mm wide by 3.0 (-0.0 + 0.2) mm thick.
2—After 37.7°C (100°F) and 100 % humidity
Refer to Test Method D5947 for guidance on measuring 3—After 60°C (140°F)
4—Final conditioning
physical dimensions of solid plastic specimens.
FIG. 2 Scribing a Test Specimen for Measurement (example)
6.2 Three specimens shall be tested for each conditioning.
6.3 Individual specimens shall be positioned vertically in
the specified environment.
NOTE 6—Acontrasting colored, permanent type marker on the surface
NOTE 4—A wire hook inserted in a hole drilled in one end of the of the specimen, in the area of the scribe has been found useful to aid in
specimen has been found acceptable. defining a sharp, clear arc.
8.2 After conditioning, reinsert one needle in the original
7. Conditioning and Exposure
centeranddrawashortarcwiththeother.Measurethedistance
7.1 Precondit
...

This document is not an 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. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D1042 − 12 (Reapproved 2017) D1042 − 22
Standard Test Method for
Linear Dimensional Changes of Plastics Caused by
Exposure to Heat and Moisture
This standard is issued under the fixed designation D1042; 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 Scope*
1.1 This test method is designed to provide a means for measuring in plastic specimens the dimensional changes of plastic
specimens such as shrinkage or expansion, developed under specific heat and water conditionings.
1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to
inch-pound units that are provided for information only and are not considered standard.
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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
NOTE 1—There is no known ISO equivalent to this standard.This standard and ISO 2796 address the same subject matter but differ in technical content.
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.
2. Referenced Documents
2.1 ASTM Standards:
D883 Terminology Relating to Plastics
D5947 Test Methods for Physical Dimensions of Solid Plastics Specimens
E456 Terminology Relating to Quality and Statistics
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
E2935 Practice for Evaluating Equivalence of Two Testing Processes
2.2 ISO Standards:
ISO 2796 Cellular plastics, rigid—Test for dimensional stability
3. Terminology
3.1 Definitions: Definitions of terms applying to this test method appear in Terminology D883.
This test method is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.50 on Durability of Plastics.
Current edition approved Aug. 1, 2017May 1, 2022. Published August 2017May 2022. Originally published asapproved in D1042 – 49T.1949. Last previous edition
approved in 2017 as D1042 – 12.D1042 – 12(2017). DOI: 10.1520/D1042-12R17.10.1520/D1042-22.
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 the ASTM website.
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D1042 − 22
3.1.1 For definitions of terms that appear in this practice relating to plastics, refer to Terminology D883.
3.1.2 For definitions of terms that appear in this practice relating to quality and statistics (such as precision and bias), refer to
Terminology E456.
4. Significance and Use
4.1 This test method is intended only as a convenient test method for measurement of linear dimensional changes in plastics
subjected to defined conditions of test as outlined in Sections 7 and 8.
5. Apparatus
5.1 Scriber, so constructed that two sharp needle points are rigidly separated by 100 6 0.2 mm. The scriber, as shown in Fig. 1,
consists of two sharp steel needles, approximately 1.5 mm in diameter. The needles are to be inserted in drilled holes with their
axes parallel to each other and perpendicular to and intersecting the long axis of a stainless steel rigid rod or bar stock, 125 6 5
mm in length. The needles’ points shall extend 6 6 2 mm beyond the supporting rod and are held in position by setscrews inserted
through the ends of the rod. The scriber shall be calibrated by scribing an arc onto an unconditioned sample and measuring this
initial scribed distance with a calibrated caliper to the nearest 0.1 mm. Thickness of arc lines shall not exceed 0.02 mm.
NOTE 2—Phonograph needles may behave been used as a satisfactory scriber.
5.2 Measuring Microscope, having a magnification of at least 20× and graduated to have a resolution of 0.01 mm.
NOTE 3—For more precise measurements, a micrometer microscope should be used. is preferred.
5.3 Caliper, 6-in., with a readability of 0.01 mm and an illuminated desk magnifier, 1.75× to 2.0× to assist with the placement
of the caliper points onto the scribed lines
5.4 Beaker, having a suitable size for the number of specimens to be evaluated and is constructed of a material that is stable under
the test conditions.
5.5 Room or Conditioning Chamber, capable of being maintained at 23 6 2°C and 50 6 10 % RH.
5.6 Conditioning Oven, full draft air-circulating oven, capable of being maintained within 62°C of the set temperature.
5.7 Absorbent Material, cloth or paper suitable for drying.
6. Test Specimens
6.1 Specimens shall not be less than 110 mm in length in the direction of test. The preferred specimen size is 125 6 5 mm in length
by 13 6 0.5 mm wide by 3.0 (-0.0 + 0.2) mm thick. Refer to Test Method D5947 for guidance on measuring physical dimensions
of solid plastic specimens.
6.2 Three specimens shall be tested for each conditioning.
6.3 Individual specimens shall be positioned vertically in the specified environment.
FIG. 1 Scriber
D1042 − 22
NOTE 4—A wire hook inserted in a hole drilled in one end of the specimen has been found acceptable.
7. Conditioning and Exposure
7.1 Preconditioning
7.1.1 Unless otherwise specified in the appropriate material specification, precondition specimens at 23 6 2°C and 50 6 10 %
relative humidity for a minimum of 40 h prior to initial scribing.
NOTE 5—If moisture equilibrium is required prior to preconditioning, refer to the specific material specifications.
7.1.2 After removal from the pre-conditioning environment, specimens shall be tested within 30 min.
7.2 Method A—Water Immersion
7.2.1 Specimens shall be immersed in water maintained at 23 6 2°C for 168 6 1 h.
7.2.2 The specimens shall be wiped dry with the absorbent cloth after removal from the water and tested within 3 min.
7.3 Method B—Oven Conditioning
7.3.1 Specimens shall be conditioned in an oven at 70 6 2°C for 25 6 1 h.
7.3.2 After removal from the oven, the specimens shall be tested within 3 min.
7.4 Other conditionings for specific service conditions can be used if agreed upon by all parties.
7.5 Conduct tests in a standard laboratory atmosphere of 23 6 2°C and 50 6 10 % relative humidity.
8. Procedure
8.1 Immediately following the preconditioning, scribe an arc of 100-mm radius on the surface of the test specimen. Press one
needle firmly into the specimen to form a center for this and subsequent measurements. The other needle scribes the arc that is
used as a reference for all subsequent measurements (see Fig. 2). Fig. 2). Draw the arcs smoothly, using a pressure consistent with
the surface hardness and test conditions to which the specimen is subjected. It is desirable to lightly scratch the surface with the
needle so that a sharp, clear arc is defined.
NOTE 6—A contrasting colored, permanent type marker may be
...