ASTM F2703-08
(Test Method)Standard Test Method for Unsteady-State Heat Transfer Evaluation of Flame Resistant Materials for Clothing with Burn Injury Prediction
Standard Test Method for Unsteady-State Heat Transfer Evaluation of Flame Resistant Materials for Clothing with Burn Injury Prediction
SIGNIFICANCE AND USE
This test method is intended for the determination of a thermal performance estimate value of a material, a combination of materials, or a comparison of different materials used in flame resistant clothing for workers exposed to combined convective and radiant thermal hazards.
This test method evaluates a material’s heat transfer properties when exposed to a heat exposure at a constant value and specific duration. Air movement at the face of the specimen and around the calorimeter can affect the measured heat transferred due to forced convective heat losses. Minimizing air movement around the specimen and test apparatus will aid in the repeatability of the results.
This test method accounts for the thermal energy stored in the exposed test specimen after the heat exposure has ceased. Higher values of Thermal Performance Estimate ratings determined in this test associate to higher values of thermal (convective and radiative) energy protection against a predicted skin burn injury.
This test method maintains the specimen in a static, horizontal position and does not involve movement except that resulting from the exposure.
This test method specifies a standardized 84 ± 2 kW/m2 (2 ± 0.05 cal/cm2s) exposure condition. Different exposure conditions have the potential to produce different results. Other exposure conditions representative of the expected hazard are allowed but shall be reported with the results along with a determination of the exposure energy level stability.
This test method contains optional provisions for conducting certification testing against a prescribed Thermal Performance Estimate value.
SCOPE
1.1 This test method measures the non-steady state heat transfer through flame resistant materials for clothing subjected to a combined convective and radiant heat exposure.
1.1.1 This test method is not applicable to materials that are not flame resistant.
Note 1—The determination of a material’s flame resistance shall be made prior to testing and done in accordance with the applicable performance and/or specification standard for the material’s end-use.
1.1.2 This test method accounts for the thermal energy contained in an exposed test specimen after the standardized combined convective and radiant heat exposure has ceased and is used to estimate performance to a predicted second-degree skin burn injury.
1.2 This test method is used to measure and describe the response of materials, products, or assemblies to heat under controlled conditions, but does not by itself incorporate all factors required for fire hazard or fire risk assessment of the materials, products, or assemblies under actual fire conditions.
1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound or other units that are commonly used for thermal testing.
1.4 This standard does not purport to address 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.
General Information
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: F2703 − 08
StandardTest Method for
Unsteady-State Heat Transfer Evaluation of Flame Resistant
Materials for Clothing with Burn Injury Prediction
This standard is issued under the fixed designation F2703; 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 D1776Practice for Conditioning and Testing Textiles
D1777Test Method for Thickness of Textile Materials
1.1 This test method measures the non-steady state heat
D3776Test Methods for Mass Per Unit Area (Weight) of
transferthroughflameresistantmaterialsforclothingsubjected
Fabric
to a combined convective and radiant heat exposure.
E457Test Method for Measuring Heat-Transfer Rate Using
1.1.1 This test method is not applicable to materials that are
a Thermal Capacitance (Slug) Calorimeter
not flame resistant.
F1494Terminology Relating to Protective Clothing
NOTE 1—The determination of a material’s flame resistance shall be
made prior to testing and done in accordance with the applicable
3. Terminology
performance and/or specification standard for the material’s end-use.
3.1 Definitions:
1.1.2 This test method accounts for the thermal energy
3.1.1 breakopen, n—in testing thermal protective materials,
contained in an exposed test specimen after the standardized
amaterialresponseevidencedbytheformationofaholeinthe
combinedconvectiveandradiantheatexposurehasceasedand
test specimen during the thermal exposure that may result in
is used to estimate performance to a predicted second-degree
the exposure energy in direct contact with the heat sensor.
skin burn injury.
3.1.1.1 Discussion—The specimen is considered to exhibit
1.2 This test method is used to measure and describe the
breakopen when a hole is produced as a result of the thermal
response of materials, products, or assemblies to heat under
2 2
exposure that is at least 3.2 cm (0.5 in. ) in area or at least 2.5
controlled conditions, but does not by itself incorporate all
cm (1.0 in.) in any dimension. Single threads across the
factors required for fire hazard or fire risk assessment of the
opening or hole do not reduce the size of the hole for the
materials, products, or assemblies under actual fire conditions.
purposes of this test method.
1.3 The values stated in SI units are to be regarded as
3.1.2 charring, n—the formation of a carbonaceous residue
standard. The values given in parentheses are mathematical
as the result of pyrolysis or incomplete combustion.
conversions to inch-pound or other units that are commonly
3.1.3 dripping,n—amaterialresponseevidencedbyflowing
used for thermal testing.
of the polymer.
1.4 This standard does not purport to address the safety
3.1.4 embrittlement, n—the formation of a brittle residue as
concerns, if any, associated with its use. It is the responsibility
a result of pyrolysis or incomplete combustion.
of the user of this standard to establish appropriate safety and
health practices and determine the applicability of regulatory
3.1.5 heat flux, n—the thermal intensity indicated by the
limitations prior to use. amountofenergytransmitteddividedbyareaandtime;kW/m
(cal/cm ·s).
2. Referenced Documents
3.1.6 ignition, n—the initiation of combustion.
2.1 ASTM Standards:
3.1.7 melting, n—a material response evidenced by soften-
D123Terminology Relating to Textiles
ing of the polymer.
3.1.8 unsteady state heat transfer value, n—in testing of
ThistestmethodisunderthejurisdictionofASTMCommitteeF23onPersonal thermal protective materials, a quantity expressed as the
ProtectiveClothingandEquipmentandisthedirectresponsibilityofSubcommittee
time-dependent difference between the incident and exiting
F23.80 on Flame and Thermal.
thermal energy values normal to and across two defined
Current edition approved July 1, 2008. Published August 2008. DOI: 10.1520/
parallel surfaces of an exposed thermal insulative material.
F2703-08.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
3.1.9 thermal performance estimate (TPE), n—in testing of
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
thermal protective materials, the cumulative amount of energy
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. identified by the intersection of a measured time-dependent
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F2703 − 08
heat transfer response through a subject material to a time- 5. Significance and Use
dependent, empirical predicted second-degree skin burn injury
5.1 This test method is intended for the determination of a
3 2
performance curve , expressed as a rating or value; J/cm
thermal performance estimate value of a material, a combina-
(cal/cm ).
tionofmaterials,oracomparisonofdifferentmaterialsusedin
3.1.10 response to heat exposure, n—in testing the resis-
flame resistant clothing for workers exposed to combined
tance to heat transfer of thermal protective materials, the
convective and radiant thermal hazards.
observable response of the material to the energy exposure as
5.2 This test method evaluates a material’s heat transfer
indicated by break-open, melting, dripping, charring,
properties when exposed to a heat exposure at a constant value
embrittlement, shrinkage, sticking, and ignition.
and specific duration. Air movement at the face of the
3.1.11 second-degree burn injury, n—in testing of thermal
specimen and around the calorimeter can affect the measured
protective materials, reversible burn damage at the epidermis/
heattransferredduetoforcedconvectiveheatlosses.Minimiz-
dermis interface in human tissue.
ing air movement around the specimen and test apparatus will
3.1.12 shrinkage, n—a decrease in one or more dimensions
aid in the repeatability of the results.
of an object or material.
5.3 This test method accounts for the thermal energy stored
3.1.13 sticking, n—a material response evidenced by soft-
in the exposed test specimen after the heat exposure has
ening and adherence of the material to the surface of itself or
ceased. Higher values of Thermal Performance Estimate rat-
another material.
ings determined in this test associate to higher values of
3.1.14 sample test suite, n—any number of test specimens
thermal (convective and radiative) energy protection against a
used to derive a single thermal performance estimate value.
predicted skin burn injury.
3.1.14.1 Discussion—the determination of a single thermal
5.4 This test method maintains the specimen in a static,
performance estimate value requires exposing a number of
specimens under varying exposure conditions so that the horizontalpositionanddoesnotinvolvemovementexceptthat
resulting from the exposure.
thermal energy stored in the sample after the heat source is
removed is considered and accounted for when determining
5.5 Thistestmethodspecifiesastandardized84 62kW/m
performance against a burn injury prediction.
(2 6 0.05 cal/cm s) exposure condition. Different exposure
3.1.15 For the definitions of protective clothing terms used
conditionshavethepotentialtoproducedifferentresults.Other
in this method, refer to Terminology F1494, and for other
exposure conditions representative of the expected hazard are
textile terms used in this method, refer to Terminology D123.
allowed but shall be reported with the results along with a
determination of the exposure energy level stability.
4. Summary of Test Method
5.6 This test method contains optional provisions for con-
4.1 Ahorizontally positioned test specimen is exposed to a
ducting certification testing against a prescribed Thermal
combined convective and radiant heat source with an exposure
2 2 Performance Estimate value.
heat flux of 84 62kW/m (2 6 0.05 cal/cm s).
NOTE 2—Other exposure heat flux values are allowed, however
6. Apparatus and Materials
different exposure conditions have the potential to produce different
results. The test facility shall verify the stability of other exposure levels
6.1 General Arrangement—The measurement apparatus
over the material’s exposure time interval (used to determine the thermal
configuration consists of a combined convective and radiant
performance estimate value) and include this in the test results report.
energyheatsource,awatercooledshutterforexposurecontrol,
4.2 The unsteady-state transfer of heat through the test
a specimen and sensor support structure, a specimen holder
specimen is measured using a copper slug calorimeter. The
assembly, a copper calorimeter sensor assembly, and a data
change in temperature versus time is used, along with the
acquisition/analysis system. Automation of the apparatus for
known thermo-physical properties of copper, to determine the
execution of the measurement procedure is allowed. The
respective thermal energy passed through the test specimen.
general arrangement of the test apparatus configuration is
4.3 A Thermal Performance Estimate value of the test shown in Fig. 1.
specimen is determined iteratively as the intersection of the
6.2 Gas Supply—Propane (commercial grade or better) or
time-dependent cumulative heat response as measured by the
Methane (technical grade or better).
calorimeter to a time-dependent, empirical predicted second-
degree skin burn injury performance curve identified in
6.3 Gas Flowmeter—Any gas flowmeter or rotometer with
10.4.1.5, Eq 1). rangetogiveaflowequivalentofatleast6L(0.21ft )/minair
at standard conditions.
4.4 Observations of the thermal response of the specimen
resulting from the exposure are optionally reported.
6.4 Thermal Energy Source
6.4.1 Two each, Meker or Fisher burners jetted for the
Derived from: Stoll,A.M. and Chianta, M.A., “Method and Rating System for
selected fuel gas (propane or methane) with a 38 mm (1.5 in.)
Evaluations of Thermal Protection”, Aerospace Medicine, Vol 40, 1969, pp.
diameter top arranged so that the bodies (top section) do not
1232-1238 and Stoll, A.M. and Chianta, M.A., “Heat Transfer through Fabrics as
obstruct the quartz lamps and their flame profiles overlap.
Related toThermal Injury”,Transactions – NewYorkAcademy of Sciences,Vol 33
(7), Nov. 1971, pp. 649-670. Dimension tolerances are 65%.
F2703 − 08
NOTE 1—Note the exposure heat source incorporates two Meker burners and nine quartz infrared lamps
FIG. 1 Apparatus used to Measure Heat Transfer Performance of Textile Materials
6.4.2 Nine 500W T3 translucent quartz infrared lamps , completelydriveoffanyremainingorganiccarriersinafreshly
connected to a variable electrical power controller, arranged as painted surface before use.
a linear array with 13 6 0.5 mm center-to-center spacing set
NOTE 3—Emissivity of painted calorimeters is discussed in theASTM
125 6 10 mm from the specimen surface.
Report, “ASTM Research Program on Electric Arc Test Method Devel-
6.4.2.1 Use of a water-cooled housing for the quartz infra-
opment to Evaluate Protective Clothing Fabric;ASTM F18.65.01 Testing
Group Report on Arc Testing Analysis of the F1959 Standard Test
red lamp bank is recommended. This helps to avoid heating
Method—Phase 1”
adjacent mechanical components and to shield the operator
from the radiant energy. 6.5.2 The thermocouple wire bead is installed in the calo-
rimeter as shown in Fig. 2.
6.5 Thermal Sensor
6.5.2.1 The thermocouple wire bead shall be bonded to the
6.5.1 Thetransmittedheatsensorisa4 60.05cmdiameter
5 copperdiskeithermechanicallyorbyusinghighmeltingpoint
circular copper slug calorimeter constructed from electrical
(HMP) solder.
gradecopperwithamassof18 60.05g(priortodrilling)with
(1)Amechanical bond shall be produced by mechanically
asingleANSItypeJ(Fe/Cu-Ni)orANSItypeK(Ni-Cr/Ni-Al)
deforming the copper disk material (utilizing a copper filling
thermocouple wire bead (0.254 mm wire diameter or finer—
slug as shown in Fig. 2) around the thermocouple bead.
equivalent to 30 AWG) installed as identified in 6.5.2 and
(2)A solder bond shall be produced by using a suitable
shown in Fig. 2. The sensor holder shall be constructed from
HMP solder with a melting temperature >280°C.
non-conductive heat resistant material with a thermal conduc-
tivity value of ≤ 0.15 W/m•K, high temperature stability, and
NOTE 4—HMP solders consisting of 5%Sb-95%Pb (~307°C melting
point) and 5%Sb-93.5%Pb-1.5%Ag (;300°C melting point) have been
resistance to thermal shock. The board shall be nominally 1.3
found to be suitable. The 280 °C temperature minimum identified above
cm (0.5 in.) or greater in thickness. The sensor is held into the
corresponds to the point where melting of the solder bond would be
recess of the board using three straight pins, trimmed to a
experienced with an ~17 second exposure of an 84 kW/m heat flux to a
nominal length of 5 mm, by placing them equidistant around
prepared copper calorimeter with a surface area of 12.57 cm and a mass
the edge of the sensor so that the heads of the pins hold the
of 18.0 g.Acareful soldering technique is required to avoid “cold” solder
joints (where the solder has not formed a suitable bond of the thermo-
sensor flush to the surface.
couple to the copper disk).
6.5.1.1 Paint the exposed surface of the copper slug calo-
6.5.3 Weight the sensor board assembly so that the total
rimeter with a thin coating of a flat black high temperature
massis1.0 60.01kgandthedownwardforceexhibitedbythe
spray paint with an absorptivity of 0.9 or greater .The painted
sensor must be dried and cured, in accordance with the copper slug sensor surface is uniform.
manufacturers instructions, before use and present a uniformly
NOTE 5—Any system of weighting that provides a uniformly weighted
applied coating (no visual thick spots or surface irregularities).
sensor is allowed. An auxiliary stainless steel plate affixed to and/or
In the absence of manufacturers instructions, an external heat individual weights placed at the top of the sensor assembly have been
found to be effective.
source, for example, an external heat lamp, shall be used to
6.6 Data Acquisition/Analysis System—A data acquisition/
analysis system is required that is capable of recording the
A500 Watt T3 120VAC quartz infrared heat lamp, product number 21651-1
from Philips Lighting Company has been used successfully in this application.
See Test Method E457 for information regarding slug calorimeters.
6 7
Zynolyte #635 from Aervoe Industries has been found suitable. Zynolyte is a Supporting data have been filed atASTM International Headquarters and may
registered trademark of the Glidden Company. be obtained
...
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