ASTM F3672-23

• Abstract:

  SIGNIFICANCE AND USE; 4.1 This test method can be used to quantify and compare the evaporative resistance imposed by different clothing items or ensembles as long as each test is conducted using the same experimental procedures and test conditions. For example, variations in the design and material used in gloves can be evaluated. The effects of layering, closures, and fit can also be measured. ; 4.2 The measurement of the evaporative resistance imposed by clothing is complex and dependent upon the apparatus and techniques used. It is not practical in a test method of this scope to establish details sufficient to cover all contingencies. Departures from the instructions in this test method have the potential to lead to significantly different test results. Technical knowledge concerning the theory of heat transfer, moisture transfer, temperature, humidity and air motion measurement, and testing practices is needed to evaluate which departures from the instructions given in this test method are significant. Standardization of the method reduces, but does not eliminate, the need for such technical knowledge. Report any departures with the results.; SCOPE; 1.1 This test method covers the determination of the evaporative resistance of clothing items that cover only the head (Option 1), a hand (Option 2), or a foot (Option 3). It describes the measurement of the resistance to evaporative heat transfer from a heated sweating thermal manikin form to the testing environment. ; 1.1.1 This is a static test that provides a baseline clothing measurement on a stationary head manikin form (Option 1), hand manikin form (Option 2), or foot manikin form (Option 3). ; 1.1.2 The effects of body form position, movement, and contact with other surfaces are not addressed in this test method. ; 1.2 The evaporative resistance values obtained apply only to the particular clothing items evaluated and for the specified environmental conditions of each test. ; 1.3 Evaporative resistance values reported in SI units shall be regarded as standard. ; 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. ; 1.5 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: 31-Oct-2023
• Technical Committee: F23 - Personal Protective Clothing and Equipment
• Drafting Committee: F23.60 - Human Factors

Overview

ASTM F3672-23 is the internationally recognized standard test method for measuring the evaporative resistance of clothing items using heated manikin body forms. Developed by ASTM, this standard enables quantification and comparison of the evaporative resistance imposed by different clothing items or ensembles covering the head, hand, or foot. The test method describes a controlled, static assessment of how clothing products affect the body’s ability to lose heat through evaporation, which is a critical factor in thermoregulation and wearer comfort.

Proper evaluation of clothing evaporative resistance helps manufacturers, researchers, and safety professionals determine product performance under specified environmental conditions. The standard supports detailed analysis of clothing design, materials, layering, closures, and fit using precise, repeatable laboratory procedures.

Keywords included: evaporative resistance, heated manikin, clothing test, thermal comfort, protective clothing, performance testing.

Key Topics

• Evaporative Resistance Measurement: Quantifies resistance to evaporative heat transfer from a heated, sweating manikin body part (head, hand, or foot) to the environment.
• Test Apparatus: Utilizes anatomically accurate, heated manikin forms with independently controlled temperature zones and active sweating systems to simulate realistic physiological conditions.
• Test Scope: Focuses on static measurements; does not account for movement or contact with surfaces. Applicable only to items evaluated under defined, uniform test environments.
• Layering and Fit: Evaluates the influence of garment design, layering schemes, closures, and fit on evaporative resistance outcomes.
• Reporting and Replicability: Emphasizes consistent documentation, including specimen preparation, environmental conditions, and any deviations from procedures to ensure reliable, comparable results.

Applications

ASTM F3672-23 is vital in a range of contexts where managing evaporative resistance is essential for comfort and safety:

• Personal Protective Equipment (PPE): Used by PPE manufacturers to test gloves, headgear, and footwear performance, ensuring optimal heat and moisture management.
• Thermal Comfort Research: Supports ergonomic and physiological studies on the influence of clothing on human thermal comfort and thermoregulation.
• Product Development: Assists textile and apparel designers in evaluating the performance of materials, assessing the impact of layering, and optimizing product features for intended use.
• Quality Assurance: Ensures that clothing marketed for high-activity, protective, or extreme-weather applications meets rigorous performance criteria.
• Certification and Compliance: Provides objective, standardized assessment for certifying compliance with industry and regulatory requirements.

Related Standards

For holistic assessment of clothing performance, ASTM F3672-23 recommends familiarity with these related standards and guidelines:

• ASTM F1291: Standard Test Method for Measuring the Thermal Insulation of Clothing Using a Heated Manikin.
• ASTM F2370: Standard Test Method for Measuring the Evaporative Resistance of Clothing Using a Sweating Manikin.
• ASTM F3426: Standard Test Method for Measuring the Thermal Insulation of Clothing Items Using Heated Manikin Body Forms.
• ASHRAE 55: Thermal Environmental Conditions for Human Occupancy - widely cited for establishing environmental variables.
• ISO 9920: Ergonomics of the Thermal Environment-Estimation of the Thermal Insulation and Evaporation Resistance of a Clothing Ensemble.

By standardizing the evaluation of evaporative resistance using heated manikin forms, ASTM F3672-23 advances safety, performance, and comfort in personal clothing and equipment, supporting informed decisions in design, manufacturing, and research.

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: F3672 − 23
Standard Test Method for
Measuring the Evaporative Resistance of Clothing Items
Using Heated Manikin Body Forms
This standard is issued under the fixed designation F3672; 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
The type of clothing worn by people directly affects the heat exchange between the human body and
the environment. The heat transfer is both sensible (conduction, convection, and radiation) and latent
(evaporation). The thermal resistance (insulation) and evaporative resistance provided by a clothing
ensemble are measured on full-body, life-size manikins according to Test Methods F1291 and F2370,
respectively. These standards also discuss measuring the local total resistance values of garments by
using only a few body parts (zones) covered by the clothing. However, more detailed data can be
obtained from a dedicated body part manikin with several zones than from a full-body manikin where
only one or two zones are used to take measurements. This detailed information about extremities is
important, as they impact human thermal comfort and are often vulnerable to thermal injury. Test
Method F3426 offers a means by which to measure detailed thermal resistance values of clothing items
intended to be worn on the extremities, but detailed evaporative resistance values for these clothing
items provide additional indicators of product performance. This is particularly true in end-use
scenarios where latent heat transfer is the dominant mechanism for thermoregulation. The resistance
values measured using body part manikins are dependent upon the designs and materials used in the
component garments, the amount of body surface area covered by clothing, distribution of the fabric
layers over the body, looseness or tightness of fit, and the increased surface area for heat loss.
Evaporative resistance measurements made on fabrics alone do not take these factors into account.
1. Scope 1.3 Evaporative resistance values reported in SI units shall
be regarded as standard.
1.1 This test method covers the determination of the evapo-
1.4 This standard does not purport to address all of the
rative resistance of clothing items that cover only the head
safety concerns, if any, associated with its use. It is the
(Option 1), a hand (Option 2), or a foot (Option 3). It describes
responsibility of the user of this standard to establish appro-
the measurement of the resistance to evaporative heat transfer
priate safety, health, and environmental practices and deter-
from a heated sweating thermal manikin form to the testing
mine the applicability of regulatory limitations prior to use.
environment.
1.5 This international standard was developed in accor-
1.1.1 This is a static test that provides a baseline clothing
dance with internationally recognized principles on standard-
measurement on a stationary head manikin form (Option 1),
ization established in the Decision on Principles for the
hand manikin form (Option 2), or foot manikin form (Option
Development of International Standards, Guides and Recom-
3).
mendations issued by the World Trade Organization Technical
1.1.2 The effects of body form position, movement, and
Barriers to Trade (TBT) Committee.
contact with other surfaces are not addressed in this test
method.
2. Referenced Documents
1.2 The evaporative resistance values obtained apply only to
2.1 ASTM Standards:
the particular clothing items evaluated and for the specified
F1291 Test Method for Measuring the Thermal Insulation of
environmental conditions of each test.
Clothing Using a Heated Manikin
This test method is under the jurisdiction of ASTM Committee F23 on Personal
Protective Clothing and Equipment and is the direct responsibility of Subcommittee For referenced ASTM standards, visit the ASTM website, www.astm.org, or
F23.60 on Human Factors. contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Current edition approved Nov. 1, 2023. Published November 2023. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/F3672-23. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F3672 − 23
F2370 Test Method for Measuring the Evaporative Resis- experimental procedures and test conditions. For example,
tance of Clothing Using a Sweating Manikin variations in the design and material used in gloves can be
F3426 Test Method for Measuring the Thermal Insulation of evaluated. The effects of layering, closures, and fit can also be
Clothing Items Using Heated Manikin Body Forms measured.
2.2 ASHRAE Standard:
4.2 The measurement of the evaporative resistance imposed
ASHRAE 55 Thermal Environmental Conditions for Human
by clothing is complex and dependent upon the apparatus and
Occupancy
techniques used. It is not practical in a test method of this scope
2.3 ISO Standard:
to establish details sufficient to cover all contingencies. Depar-
ISO 9920 Ergonomics of the Thermal Environment—
tures from the instructions in this test method have the potential
Estimation of the Thermal Insulation and Evaporation
to lead to significantly different test results. Technical knowl-
Resistance of a Clothing Ensemble
edge concerning the theory of heat transfer, moisture transfer,
temperature, humidity and air motion measurement, and testing
3. Terminology
practices is needed to evaluate which departures from the
3.1 Definitions:
instructions given in this test method are significant. Standard-
3.1.1 clothing ensemble, n—a group of garments worn
ization of the method reduces, but does not eliminate, the need
together on the body at the same time (for example, sock and
for such technical knowledge. Report any departures with the
boot).
results.
3.1.2 clothing item, n—a garment or product worn as part of
5. Apparatus
the clothing ensemble or separately.
3.1.2.1 Discussion—This standard only addresses clothing
5.1 Manikin Body Forms:
items or ensembles worn on the head, a hand, or a foot.
5.1.1 Option 1 – Head Manikin:
Clothing ensembles may be comprised of a single clothing item
5.1.1.1 Manikin—Use a manikin head form that is the size
or a system of multiple clothing items. For example, some
and shape of a representative human and heated to a constant,
handwear systems consist of multiple gloves (for example,
average surface temperature.
liner and shell), mittens, or both. Clothing ensembles com-
5.1.1.2 Size and Shape—The manikin head shall be con-
prised of multiple distinct items may be evaluated using this
structed to simulate the head of a human being; that is, it shall
test method.
consist of a head, chin, and nose. Ear protrusions are not
3.1.3 clothing area factor (f ), n—the ratio of the surface
required. Total surface area shall be 0.134 m 615 %.
cl
area of the clothed body form to the surface area of the nude
5.1.1.3 Manikin Zones—Construct the manikin head form
body form.
with no less than four independent temperature-controlled
zones. At a minimum the top of the head, the back of the head,
3.1.4 evaporative resistance, n—the resistance to the evapo-
the eye/forehead area, and the mouth area shall be independent
rative heat transfer from the body to the environment.
zones.
3.1.4.1 Discussion—The evaporative resistance in units of
kPa·m /W can be calculated for several different cases: 5.1.1.4 Guard Zone—Construct the manikin head form with
a guard zone butting up against the terminus of the head/neck
R = evaporative resistance of the air layer on the surface
ea
(where the head form would connect to the rest of a body if it
of the sweating nude manikin body form,
were a full-body manikin). Heat this zone to the same constant
R = total evaporative resistance of the clothing and surface
et
temperature as all other zones to prevent unwanted heat loss
air layer around the manikin body form, and
from the manikin head form into the apparatus or environment.
R = intrinsic evaporative resistance of the clothing.
ecl
This zone shall not be included as one of the four required
manikin zones.
3.1.4.2 Discussion—Total evaporative resistance values are
5.1.2 Option 2 – Hand Manikin:
measured directly with a manikin. Intrinsic clothing evapora-
tive resistance values are determined by subtracting the air 5.1.2.1 Manikin—Use a hand manikin form that is the size
layer resistance around the clothed manikin from the total and shape of a representative human’s left or right hand and
evaporative resistance value for the clothing item (or en- heated to a constant, average surface temperature.
semble).
5.1.2.2 Size and Shape—The hand manikin shall be con-
structed to simulate the hand and wrist/forearm of an adult
4. Significance and Use
human being; that is, it shall consist of a wrist/forearm, palm
and back of hand, four finger digits, and a thumb digit with
4.1 This test method can be used to quantify and compare
fingers extended to allow gloves to be worn. Total surface area
the evaporative resistance imposed by different clothing items
of form shall be 0.069 m 615 %.
or ensembles as long as each test is conducted using the same
NOTE 1—Based on the specified manikin dimensions, use appropriately
sized glove specimens approximately size 8 to 10 (medium to large).
Available from American Society of Heating, Refrigerating, and Air-
Conditioning Engineers, Inc. (ASHRAE), 180 Technology Pkwy., NW, Peachtree
5.1.2.3 Manikin Zones—Construct the manikin hand form
Corners, GA 30092, http://www.ashrae.org.
with no less than four independent temperature-controlled
Available from International Organization for Standardization (ISO), ISO
zones. At a minimum the palm, the fingers, the back of the
Central Secretariat, Chemin de Blandonnet 8, CP 401, 1214 Vernier, Geneva,
Switzerland, https://www.iso.org. hand, and the wrist shall be independent zones.
F3672 − 23
5.1.2.4 Guard Zone—Construct the manikin hand form with 5.4 Power Measuring Instruments—Power to the manikin
a guard zone butting up against the terminus of the wrist/ form shall be measured so as to give an average over the period
forearm (where the hand form would connect to the rest of a of a test. If time proportioning or phase proportioning is used
body if it were a full-body manikin). Heat this zone to the same for power control, then devices that are capable of averaging
constant temperature as all other zones to prevent unwanted over the control cycle are required. Integrating devices (watt-
heat loss from the manikin hand form into the apparatus or hour meters) are preferred over instantaneous devices (watt
environment. This zone shall not be included as one of the four meters). Overall accuracy of the power monitoring equipment
required manikin zones. must be within 62 % of the reading for the average power for
the test period. Since there are a variety of devices and
5.1.3 Option 3 – Foot Manikin:
techniques used for power measurement, no specified calibra-
5.1.3.1 Manikin—Use a foot manikin form that is the size
tion procedures shall be given. However, an appropriate power
and shape of a representative human’s left or right foot and
calibration procedure is to be developed and documented.
heated to a constant, average surface temperature.
5.1.3.2 Size and Shape—The foot manikin shall be con-
5.5 Equipment for Measuring the Manikin’s Surface (Skin)
structed to simulate the foot and ankle/lower leg of an adult
Temperature—The mean surface temperature shall be mea-
human being; that is, it shall consist of an ankle/lower leg and
sured with point sensors or distributed temperature sensors.
an approximate foot form. The foot must have an overall shape
5.5.1 Point Sensors—Point sensors shall be thermocouples,
that is representative of a human foot; however, it is not
resistance temperature devices (RTDs), thermistors, or equiva-
necessary for the manikin to have individual toe digits. Total
lent sensors. They shall be no more than 2 mm thick and shall
surface area of the foot form shall be 0.096 m 615 %.
be well bonded, both mechanically and thermally, to the
manikin’s body form surface. Lead wires shall be bonded to the
NOTE 2—Based on the specified manikin dimensions, use appropriately
surface or pass through the interior of the manikin, or both.
sized shoe specimens approximately size US 9M to 10.5M (EU 43 to 44).
Each sensor temperature shall be area-weighted when calcu-
5.1.3.3 Manikin Zones—Construct the manikin foot form
lating the mean surface temperature for the body form. If point
with no less than four independent temperature-controlled
sensors are used, apply at least one point sensor in each zone
zones. At a minimum the bottom of the foot, the toes, the top
of the manikin body form.
of the foot, and the ankle/leg area shall be independent zones.
5.5.2 Distributed Sensors—If distributed sensors are used
5.1.3.4 Guard Zone—Construct the manikin foot form with
(for example, resistance wire), then the sensors must be
a guard zone butting up against the terminus of the lower leg
distributed over the surface so that all areas are equally
(where the foot form would connect to the rest of a body if it
weighted. If several such sensors are used to measure the
were a full-body manikin). Heat this zone to the same constant
temperature of different zones of the manikin, then their
temperature as all other zones to prevent unwanted heat loss
respective temperatures shall be area-weighted when calculat-
from the manikin hand form into the apparatus or environment.
ing the mean surface temperature. Distributed sensors shall be
This zone shall not be included as one of the four required
less than 1 mm in diameter and firmly attached to the manikin
manikin zones.
surface at all points.
5.2 Sweat Generation—The manikin must have the ability
5.6 Controlled Environmental Chamber—The manikin shall
to evaporate water from its entire surface. The sweating system
be placed in a chamber that can provide uniform conditions,
can be a tight-fitting, continuously water fed capillary body suit
both spatially and temporally.
worn over the thermal manikin. Sweating can also be simulated
5.6.1 Spatial Variations—Spatial variations shall not exceed
by supplying water and maintaining it at the inner surface of a
the following: air temperature 61.0 °C, relative humidity
waterproof but vapor-permeable fabric skin.
65 %, and air velocity 650 % of the mean value. In addition,
5.2.1 Sweating Surface Area—The entire surface of the
the mean radiant temperature shall not be more than 1.0 °C
manikin shall be heated and covered by the active sweating
different from the mean air temperature. The spatial uniformity
system, except for the thermal guard zone which shall not
shall be verified at least annually or after any significant
sweat.
modifications are made to the chamber. Spatial uniformity shall
5.2.2 Water—The water used within the sweating system
be verified by recording values for the conditions stated above
shall be distilled, deionized, or reverse-osmosis treated.
at two distinct heights. Take the measurements at two locations
with the manikin form in place at a position 0.2 m 6 0.05 m in
5.3 Surface Temperature—The manikin body form shall be
constructed so as to maintain a uniform temperature distribu- front of the manikin’s closest undressed point. Sensors shall be
aligned with the center of the manikin form and located 50 mm
tion over the nude body surface, with no local hot or cold spots.
The mean surface (skin) temperature of the manikin body form 6 10 mm below the top of the manikin form and 50 mm 6
10 mm above the bottom of the manikin form.
shall be 35 °C. Local deviations from the mean skin tempera-
ture shall not exceed 60.3 °C. Temperature uniformity of the 5.6.2 Temporal Variations—Temporal variations shall not
exceed the following: air temperature 60.5 °C, mean radiant
nude manikin body form shall be evaluated at least once
annually or after repairs or alterations are completed that could temperature 60.5 °C, relative humidity 65 %, air velocity
625 % of the mean value for data averaged over 5 min (see
affect temperature uniformity, for example, replacement of a
heating element. Due to variation in manikin body part forms, 5.6.5).
consulting with the manikin manufacturer for an appropriate 5.6.3 Relative Humidity Measuring Equipment—Any hu-
method is recommended. midity sensing device with an accuracy of 65 % relative
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