ASTM D7984-21

Standard Test Method for Measurement of Thermal Effusivity of Fabrics Using a Modified Transient Plane Source (MTPS) Instrument

SIGNIFICANCE AND USE
5.1 This test method measures the rate of thermal transport between a heating element and a fabric specimen. Some of the comfort properties of a garment relate to initial thermal sensations (that is, cold or warm feeling upon initial contact), where lower thermal effusivity values indicate sensations of warmth and higher values indicate sensations of coolness. The thermal effusivity of different fabrics and their initial perceived surface temperature are important to assist product developers with fabric selection.  
5.2 The sensor and the test specimen being measured shall be at the same temperature for measurements at standard conditions. This test method may be applied to any fabric with a thermal effusivity in the range of 35 to 1700 Ws1/2/m2·K.  
5.3 Air flow shall be kept at a minimum to ensure temperature fluctuations do not occur during the measurement.
SCOPE
1.1 This test method covers the quantitative measurement of thermal effusivity of woven, knitted, or non-woven fabrics using a guarded modified transient plane source (MTPS) instrument.4 This test method is applicable to a wide range of thicknesses; however, the thickness of the specimen must be greater than the penetration depth of the heat flux during the measurement time.  
1.2 This test method is comparative since specimens of known thermal effusivity are used to calibrate the apparatus at the factory level. Thermal effusivity of the calibration specimens are confirmed through calculations that use established properties of thermal conductivity, density, and specific heat.  
1.3 This test method is intended for measuring fabrics in a dry state at ambient conditions.  
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.5 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.  
1.6 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: 30-Jun-2021
• ICS: 59.080.30 - Textile fabrics
• Technical Committee: D13 - Textiles
• Drafting Committee: D13.51 - Conditioning, Chemical and Thermal Properties

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: D7984 −21
Standard Test Method for
Measurement of Thermal Effusivity of Fabrics Using a
1
Modified Transient Plane Source (MTPS) Instrument
This standard is issued under the fixed designation D7984; 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.
INTRODUCTION
This standard provides a test method for measuring the thermal effusivity of fabrics under still air
conditions. Other standards, Test Methods F1868 and D1518, measure the thermal insulation of
materials under steady-state conditions; however, this test method is used to measure transient heat
exchangebetweenafabricspecimenandaheatedsurface.Ithasbeenestablishedthatthereisastrong
positive correlation between the thermal effusivity and the initial perceived coldness between human
2,3
skin and different materials.
1. Scope 1.5 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
1.1 Thistestmethodcoversthequantitativemeasurementof
responsibility of the user of this standard to establish appro-
thermal effusivity of woven, knitted, or non-woven fabrics
priate safety, health, and environmental practices and deter-
using a guarded modified transient plane source (MTPS)
4 mine the applicability of regulatory limitations prior to use.
instrument. This test method is applicable to a wide range of
1.6 This international standard was developed in accor-
thicknesses; however, the thickness of the specimen must be
dance with internationally recognized principles on standard-
greater than the penetration depth of the heat flux during the
ization established in the Decision on Principles for the
measurement time.
Development of International Standards, Guides and Recom-
1.2 This test method is comparative since specimens of
mendations issued by the World Trade Organization Technical
known thermal effusivity are used to calibrate the apparatus at
Barriers to Trade (TBT) Committee.
the factory level. Thermal effusivity of the calibration speci-
mens are confirmed through calculations that use established 2. Referenced Documents
properties of thermal conductivity, density, and specific heat. 5
2.1 ASTM Standards:
1.3 This test method is intended for measuring fabrics in a D123Terminology Relating to Textiles
dry state at ambient conditions.
D1518Test Method for Thermal Resistance of Batting
Systems Using a Hot Plate
1.4 The values stated in SI units are to be regarded as
D1776Practice for Conditioning and Testing Textiles
standard. No other units of measurement are included in this
D4920Terminology Relating to Conditioning, Chemical,
standard.
and Thermal Properties
E691Practice for Conducting an Interlaboratory Study to
1
ThistestmethodisunderthejurisdictionofASTMCommitteeD13onTextiles
Determine the Precision of a Test Method
andisthedirectresponsibilityofSubcommitteeD13.51onConditioning,Chemical
and Thermal Properties.
E177Practice for Use of the Terms Precision and Bias in
Current edition approved July 1, 2021. Published August 2021. Originally
ASTM Test Methods
approved in 2016. Last previous edition approved in 2016 as D7984–16. DOI:
F1868Test Method forThermal and Evaporative Resistance
10.1520/D7984-21.
2
of Clothing Materials Using a Sweating Hot Plate
Marin, E., “Teaching Thermal Physics by Touching,” Latin-American Journal
of Physics Education, Vol 2, No. 1, January 2008, pp. 15-17.
3
Wongsriruska, S., Howes, P., Conreen, M., Miodownik, M., “The Use of
3. Terminology
PhysicalPropertyDatatoPredicttheTouchPerceptionofMaterials,” Materials and
3.1 Definitions of Terms Specific to This Standard:
Design, Vol 42, 2012, pp. 238-244.
4
ThesolesourceofsupplyoftheTCiinstrumentknowntothecommitteeatthis
time is C-Therm Technologies, Ltd., C/O RPC, 921 College Hill Rd., Fredericton,
5
NewBrunswick,Canada,E3B6Z9.Ifyouareawareofalternativesuppliers,please For referenced ASTM standards, visit the ASTM website, www.astm.org, or
provide this information toASTM International Headquarters.Your comments will contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
1
receive careful consideration at a meeting of the responsible technical committee, Standards volume information, refer to the standard’s Document Summary page on
which you may attend. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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D
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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: D7984 − 16 D7984 − 21
Standard Test Method for
Measurement of Thermal Effusivity of Fabrics Using a
1
Modified Transient Plane Source (MTPS) Instrument
This standard is issued under the fixed designation D7984; 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.
INTRODUCTION
This standard provides a test method for measuring the thermal effusivity of fabrics under still air
conditions. Other standards, Test Methods F1868 and D1518, measure the thermal insulation of
materials under steady-state conditions; however, this test method is used to measure transient heat
exchange between a fabric specimen and a heated surface. It has been established that there is a strong
positive correlation between the thermal effusivity and the initial perceived coldness between human
2,3
skin and different materials.
1. Scope
1.1 This test method covers the quantitative measurement of thermal effusivity of woven, knitted, or non-woven fabrics using a
4
guarded modified transient plane source (MTPS) instrument. This test method is applicable to a wide range of thicknesses;
however, the thickness of the specimen must be greater than the penetration depth of the heat flux during the measurement time.
1.2 This test method is comparative since specimens of known thermal effusivity are used to calibrate the apparatus at the factory
level. Thermal effusivity of the calibration specimens are confirmed through calculations that use established properties of thermal
conductivity, density, and specific heat.
1.3 This test method is intended for measuring fabrics in a dry state at ambient conditions.
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 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.
1.6 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.
1
This test method is under the jurisdiction of ASTM Committee D13 on Textiles and is the direct responsibility of Subcommittee D13.51 on Conditioning, Chemical and
Thermal Properties.
Current edition approved Feb. 15, 2016July 1, 2021. Published March 2016August 2021. Originally approved in 2016. Last previous edition approved in 2016 as
D7984–16. DOI: 10.1520/D7984-16.10.1520/D7984-21.
2
Marin, E., “Teaching Thermal Physics by Touching,” Latin-American Journal of Physics Education, Vol 2, No. 1, January 2008, pp. 15-17.
3
Wongsriruska, S., Howes, P., Conreen, M., Miodownik, M., “The Use of Physical Property Data to Predict the Touch Perception of Materials,” Materials and Design,
Vol 42, 2012, pp. 238-244.
4
The sole source of supply of the TCi instrument known to the committee at this time is C-Therm Technologies, Ltd., C/O RPC, 921 College Hill Rd., Fredericton, New
Brunswick, Canada, E3B 6Z9. If you are aware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive
1
careful consideration at a meeting of the responsible technical committee, which you may attend.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D7984 − 21
2. Referenced Documents
5
2.1 ASTM Standards:
D123 Terminology Relating to Textiles
D1518 Test Method for Thermal Resistance of Batting Systems Using a Hot Plate
D1776 Practice for Conditioning and Testing Textiles
D4920 Terminology Relating to Conditioning, Chemical, and Thermal Properties
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
F1868 Test Method for Thermal and Evaporative Resistance of Clothing Materials Using a Sweating Hot Plate
3. Terminology
3.1 Definitions of
...