Standard Test Method for Measuring the Heat Removal Rate of Personal Cooling Systems Using a Sweating Heated Manikin

SIGNIFICANCE AND USE
This test method can be used to quantify and compare the cooling provided by different Personal Cooling Systems (PCS’s) worn with a standard outer garment or with any other specified one.
4.1.1 The test method is intended to allow garments based on various cooling technologies to be evaluated fairly and objectively, by taking into account convective and evaporative heat transfer.
4.1.2 A sweating thermal manikin accurately accounts for evaporative cooling, which represents the only active means of heat transfer occurring in humans. Utilizing a sweating thermal manikin will also permit the heat removal rate to be measured for all types of PCS.
The measurements of heat removal rates and duration of cooling provided by the PCS’s depend on the apparatus and techniques used.
4.2.1 It is not practical in a test method of this scope to establish details sufficient to cover all contingencies.
4.2.2 Departures from the instructions in this test method will potentially lead to significantly different test results.
4.2.3 Technical knowledge concerning the theory of heat transfer, temperature, air motion measurement, evaporative cooling, and testing practices is needed to evaluate which departures from the instructions given in this test method are significant. Report any departures with the results.
SCOPE
1.1 This test method covers the measurement of heat removal rate from a sweating heated manikin as well as the duration of cooling provided by a cooling garment, in order to assess the effectiveness of PCS.
1.1.1 This test method requires the use of a sweating heated manikin. The sweating capability is essential, to take into account the potentially large fraction of heat dissipation associated with evaporative cooling.
1.2 The experimental values obtained for the cooling rates and cooling duration apply only to the particular PCS and additional clothing ensemble (standard outer garment, outer garment integrated to the PCS, or any other outer garment, as appropriate) as tested, and for the specified environmental conditions.
1.3 The values stated in this standard shall be SI units.
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.

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information.
Designation:F2371–05
Standard Test Method for
Measuring the Heat Removal Rate of Personal Cooling
Systems Using a Sweating Heated Manikin
This standard is issued under the fixed designation F2371; 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
Personal Cooling Systems (PCS) are used when wearers could be exposed to conditions that render
thebody’sthermoregulatorysysteminadequatetomaintainbodycoretemperaturewithinasaferange.
The use of PCS can reduce the possibility of heat stress related physiological disorders and can also
provide increased comfort, which in turn could also result in higher productivity. Cooling needs vary
greatly depending on the level of activity, the external temperature and humidity, as well as the
personal protective equipment worn. The PCS should be selected that is best suited for the specific
application. Sweating heated manikins provide a convenient tool to assess the effectiveness of PCS as
they can provide objective and repeatable results. These instruments can be used to quantify, in a
reproducible manner, the cooling rate and cooling duration provided by the PCS while eliminating the
variables associated with human physiology. Sweating heated manikins can be used for direct
comparisons of PCS.
1. Scope priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
1.1 This test method covers the measurement of heat re-
moval rate from a sweating heated manikin as well as the
2. Referenced Documents
duration of cooling provided by a cooling garment, in order to
2 2.1 ASTM Standards:
assess the effectiveness of PCS.
F1291 Test Method for Measuring the Thermal Insulation
1.1.1 This test method requires the use of a sweating heated
of Clothing Using a Heated Manikin
manikin. The sweating capability is essential, to take into
F1494 Terminology Relating to Protective Clothing
account the potentially large fraction of heat dissipation asso-
F2370 Test Method for Measuring the Evaporative Resis-
ciated with evaporative cooling.
tance of Clothing Using a Sweating Manikin
1.2 The experimental values obtained for the cooling rates
and cooling duration apply only to the particular PCS and
3. Terminology
additional clothing ensemble (standard outer garment, outer
3.1 Definitions:
garment integrated to the PCS, or any other outer garment, as
3.2 clo, n—unit of thermal resistance defined as the insula-
appropriate) as tested, and for the specified environmental
tion required to keep a resting man (producing heat at the rate
conditions.
of 58 W/m ) comfortable in an environment at 21°C, air
1.3 The values stated in this standard shall be SI units.
velocity 0.1 m/s, or roughly the insulation value of typical
1.4 This standard does not purport to address all of the
indoor clothing.
safety concerns, if any, associated with its use. It is the
3.2.1 Discussion—Numerically, the clo is equal to 0.155
responsibility of the user of this standard to establish appro-
K·m /W.
3.3 clothing ensemble, n—a group of garments worn to-
1 gether on the body at the same time.
This test method is under the jurisdiction of ASTM Committee F23 on
3.4 garment, n—a single item of clothing (for example,
Protective Clothing and is the direct responsibility of Subcommittee F23.60 on
Human Factors.
shirt).
Current edition approved March 1, 2005. Published November 2005. DOI:
10.1520/F2371-05.
2 3
The present standard does not attempt to determine the thermal insulation and For referenced ASTM standards, visit the ASTM website, www.astm.org, or
evaporative resistance of garments worn with the PCS, or these same properties for contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
the PCS’s themselves. Test Methods F1291 and F2370 are available for these Standards volume information, refer to the standard’s Document Summary page on
measurements. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
F2371–05
3.5 thermal insulation, n—the resistance to dry heat transfer 5.1.3 Surface Temperature—The manikin shall be con-
by way of conduction, convection, and radiation. structed so as to maintain a constant uniform temperature over
3.6 total heat loss, n—the amount of heat transferred the nude body surface, with no local hot or cold spots.The skin
throughaclothingsystembythecombineddryandevaporative temperature of the manikin shall be 35°C. Local deviations
heat exchanges under specified conditions expressed in watts from the mean skin temperature shall not exceed 60.3°C.
per square metre. Temperature uniformity of the nude manikin shall be evaluated
3.7 For definitions of terms related to protective clothing at least once annually using an infrared thermal imaging
used in this test method, refer to Terminology F1494. system or equivalent method. Repeat this procedure after
repairs or alterations are completed that could affect tempera-
4. Significance and Use
ture uniformity (for example, replacement of a heating ele-
4.1 This test method can be used to quantify and compare
ment).
the cooling provided by different Personal Cooling Systems
5.2 Power-Measuring Instruments—Record the time his-
(PCS’s) worn with a standard outer garment or with any other
tory of the power input to the manikin over the entire test
specified one.
period. Overall accuracy of the power monitoring equipment
4.1.1 The test method is intended to allow garments based
must be within 62 % of the reading for the average power for
on various cooling technologies to be evaluated fairly and
the test period. Since there are a variety of devices and
objectively, by taking into account convective and evaporative
techniques used for power measurement, no specified calibra-
heat transfer.
tion procedures shall be given. However, an appropriate power
4.1.2 A sweating thermal manikin accurately accounts for
calibration procedure is to be developed and documented.
evaporative cooling, which represents the only active means of
5.3 Equipment for Measuring the Manikin’s Skin
heat transfer occurring in humans. Utilizing a sweating thermal
Temperature—Measure the mean skin temperature with point
manikin will also permit the heat removal rate to be measured
sensors or distributed temperature sensors.
for all types of PCS.
5.3.1 Point Sensors—Point sensors may be thermocouples,
4.2 The measurements of heat removal rates and duration of
resistancetemperaturedevices(RTD’s),thermistors,orequiva-
cooling provided by the PCS’s depend on the apparatus and
lentsensors.Theyshallbenomorethan2.0mmthickandshall
techniques used.
be well bonded, both mechanically and thermally, to the
4.2.1 It is not practical in a test method of this scope to
manikin’s surface. Lead wires shall be bonded to the surface or
establish details sufficient to cover all contingencies.
pass through the interior of the manikin, or both. The sensors
4.2.2 Departures from the instructions in this test method
shallbedistributedsothateachonerepresentsthesamesurface
will potentially lead to significantly different test results.
area or are area-weighted when calculating the mean skin
4.2.3 Technical knowledge concerning the theory of heat
temperature for the body. A minimum of 15 point sensors are
transfer, temperature, air motion measurement, evaporative
required.At least one sensor shall be placed on the head, chest,
cooling, and testing practices is needed to evaluate which
back,abdomen,buttocks,andboththerightandleftupperarm,
departures from the instructions given in this test method are
lower arm, hand, thigh, calf, and foot. These sensors must be
significant. Report any departures with the results.
placed in the same position for each test and the placement of
the sensors shall be given in the report.
5. Apparatus
5.3.2 Distributed Sensors—If distributed sensors are used
5.1 Manikin—A standing sweating manikin having the
(for example, resistance wire), then the sensors must be
form, shape, and size of an adult male or female shall be used.
distributed over the surface so that all areas are equally
The manikin shall be heated to a uniform, constant, skin
weighted. If several such sensors are used to measure the
temperature.
temperature of different parts of the body, then their respective
5.1.1 Size and Shape—The manikin shall be constructed to
temperatures should be area-weighted when calculating the
simulate the body of a human being; that is, it shall consist of
mean skin temperature. Distributed sensors must be small in
ahead,chest/back,abdomen,buttocks,arms,hands(preferably
diameter (that is, less than 1.0 mm) and firmly bonded to the
with fingers extended to allow gloves to be worn), legs, and
manikin surface at all points.
feet. Total surface area shall be 1.8 6 0.3 m , and height shall
5.4 Controlled Environmental Chamber—The manikin
be170 610cm.Themanikin’sdimensionsshallcorrespondto
shallbeplacedinachamberatleast2by2by2mindimension
those required for standard sizes of garments because devia-
that can provide uniform conditions, both spatially and tempo-
tions in fit will significantly affect the results.
rally.
5.1.2 Sweat Generation—Themanikinmusthavetheability
to evaporate water from its surface. Some examples of a 5.4.1 Spatial Variations—Spatialvariationsshallnotexceed
sweating system include a cotton body suit saturated with the following: air temperature 61.0°C, relative humidity
water or water fed capillary body suit worn over a thermal 65 %, and air velocity 650 % of the mean value. In addition,
manikin. Other technologies exist that deliver water to the the mean radiant temperature shall not be more than 1.0°C
manikin’s surface with a valve delivery system. different from the mean air temperature.The spatial uniformity
5.1.2.1 Sweating Surface Area—The surface area from shall be verified at least annually or after any significant
which water is evaporated must include the chest, back, modificationsaremadetothechamber.Spatialuniformityshall
abdomen, buttocks, arms and legs. Ideally, the manikin’s head, be verified by recording values for the conditions stated above
hands, and feet should be sweating also. at heights of 0.1, 0.6, 1.1, 1.4, and 1.7 m above the floor at the
F2371–05
location occupied by the manikin. Sensing devices specified for all tests. The mean skin temperature shall not be allowed to
below shall be used when measuring the environmental con- drift more than 60.1°C during a 2-hour test.
ditions.
7.3 Sweating—The manikin surface must have water avail-
5.4.2 Temporal Variations—Temporal variations shall not
able for evaporation throughout the test period. The amount of
exceed the following: air temperature 60.5°C, mean radiant
water on the surface should be the supplied or added to the
temperature 60.5°C, relative humidity 65 %, air velocity
surface of the manikin in the same manner as was used to
620 % of the mean value for data averaged over 5 minutes.
generate the evaporative resistance value during calibration
(See 5.4.5).
(see 5.5).
5.4.3 Relative Humidity Measuring Equipment—Any
7.3.1 Manikins without sweating heads, hands or feet can-
humidity-sensing device with an accuracy of 65 % relative
notbeusedtoevaluatePCSthatprovidecoolingtotheseareas.
humidity and a repeatability of 63 % is acceptable (for
These manikins can only evaluate PCS that provide cooling to
example, wet bulb/dry bulb, dew point hygrometer). Only one
the arms, legs, torso chest and back.
location needs to be monitored during a test to ensure that the
7.3.2 Areas that do not have a sweating surface must be
temporal uniformity requirements are met.
heated to properly simulate heat production in a human body.
5.4.4 Air Temperature Sensors—Shielded air temperature
7.4 Saturate the manikin’s sweating surface with water.
sensors shall be used. Any sensor with an overall accuracy of
Water added to the manikin’s sweating surface must be heated
60.15°C is acceptable (for example, RTD, thermocouple,
to 35 6 0.5°C before being delivered to the manikin.
thermistor). The sensor shall have a time constant not exceed-
ing 1 minute. The sensor(s) shall be 0.5 m in front of the 7.4.1 Discussion—Saturation can usually be detected visu-
manikin. If a single sensor is used it shall be 1.0 m above the ally however, if needed an IR camera can insure that the
floor. If multiple sensors are used, they shall be spaced at equal surface is completely saturated.
height intervals and their readings averaged.
7.5 Baseline Test—First, carry out a baseline test without
5.4.5 Air Velocity Indicator—Anomni-directionalanemom-
cooling. Perform this test with the PCS ensemble placed on the
eter with 60.05 m/s accuracy shall be used.Average measure-
manikin, but turned off, if possible, so that no cooling is
ments for a minimum of at least 1 min at each location. If it is
provided. In the case where the PCS cannot be turned off (for
demonstrated that velocity does not vary temporally by more
example, ice vest, or phase change material), carry out the
than 60.05 m/s, then it is not necessary to monitor air velocity
baseline test with the PCS in equilibrium with the atmosphere
during a test. The value of the mean air velocity must be
in the test chamber by previously conditioning it in the
reported, however. If air velocity is monitored, then measure-
chamber for at least 12 hours.
ment location requirements are the same as for temperature.
7.5.1 Dress the standing manikin in the garment(s) to be
5.5 Calibration—Calibrate the sweating heated manikin in
tested, together with light shorts and a t-shirt (shorts and t-shirt
accordance with Test Method F2370.
directly on the skin), and the outer garment (either coveralls
having a clo value of 1, or any other specified outer garment).
6. Sampling, Test Specimens, and Test Units
Record a description of the garment(s) and the dressing
6.1 Personal Cooling System—It is sufficient to test only
procedures. Position the manikin so that it is standing with its
one sample personal cooling system, with replicate measure-
arms hanging straight at its sides. Follow the manufacturer’s
ments made on that single sample.
instructions as to the sequence of clothing (for example, PCS
6.1.1 Size and Fit—Select the size of the PCS garment that
or t-shirt closer to the skin).
best fits the manikin. Base fit on the manufacturer’s designed
7.5.2 The baseline test involves determining the power
specifications for fitting the garment to an actual human body.
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