Standard Practice for Conducting Tests on Sealants Using Artificial Weathering Apparatus

SIGNIFICANCE AND USE
5.1 This practice determines the effects of actinic radiation, elevated temperature, and moisture on sealants and their constituents under controlled laboratory artificial weather test conditions.  
5.2 When conducting exposures in devices which use laboratory light sources, it is important to consider (1) how well the artificial test conditions will reproduce property changes and failure modes caused by end-use environments on the sealant being tested and (2) the stability ranking of sealants. Refer to Practice G151 for full cautionary guidance regarding laboratory weathering.  
5.3 Because of differences in the spectral power distributions of the exposure sources (xenon arc, fluorescent UV lamps, and open flame carbon arc), as well as other conditions used in the three types of laboratory weathering tests, including temperature, type and amount of moisture, and test cycles, these three procedures may not result in the same performance ranking or types of failure modes of sealants. Further, different exposure durations may be required for testing the weathering performance of sealants by the three types of exposures. Comparisons should not be made of the relative stability of sealants exposed in the different types of apparatus.  
5.4 Variations in results may be expected when operating conditions are varied within the accepted limits of this practice. Therefore, all test results using this practice must be accompanied by a report of the specific operating conditions as required in Section 10. Refer to Practice G151 for detailed information on the caveats applicable to use of results obtained according to this practice.  
5.5 No laboratory exposure test can be specified as a total simulation of actual use conditions in outdoor environments. The relative durability of materials in actual use conditions can vary in different locations because of differences in UV radiation, time of wetness, relative humidity, temperature, pollutants, and other factors. Results ob...
SCOPE
1.1 This practice covers three types of laboratory weathering exposure procedures for evaluating the effect of actinic radiation, heat, and moisture on sealants.  
1.2 The exposure sources used in the three types of artificial weathering devices are the filtered xenon arc, fluorescent ultraviolet lamps, and open flame carbon arc based on Practices G155, G154, and G152, respectively.  
1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.  
1.4 The ISO standard related to this Practice is ISO 11431. Significant differences exist between the procedures. The ISO specimens are exposed through glass and are elongated prior to examination for loss of adhesion or cohesion, or both, following exposure.  
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.

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Publication Date
30-Apr-2021
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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: C1442 −14 (Reapproved 2021)
Standard Practice for
Conducting Tests on Sealants Using Artificial Weathering
Apparatus
This standard is issued under the fixed designation C1442; 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 G113 Terminology Relating to Natural andArtificial Weath-
ering Tests of Nonmetallic Materials
1.1 This practice covers three types of laboratory weather-
G141 Guide for Addressing Variability in Exposure Testing
ing exposure procedures for evaluating the effect of actinic
of Nonmetallic Materials
radiation, heat, and moisture on sealants.
G147 Practice for Conditioning and Handling of Nonmetal-
1.2 The exposure sources used in the three types of artificial
lic Materials for Natural and Artificial Weathering Tests
weathering devices are the filtered xenon arc, fluorescent
G151 Practice for Exposing Nonmetallic Materials inAccel-
ultravioletlamps,andopenflamecarbonarcbasedonPractices
erated Test Devices that Use Laboratory Light Sources
G155, G154, and G152, respectively.
G152 Practice for Operating Open Flame Carbon Arc Light
Apparatus for Exposure of Nonmetallic Materials
1.3 The values stated in SI units are to be regarded as
standard. The values given in parentheses after SI units are G154 Practice for Operating Fluorescent Ultraviolet (UV)
Lamp Apparatus for Exposure of Nonmetallic Materials
provided for information only and are not considered standard.
G155 Practice for Operating XenonArc LightApparatus for
1.4 The ISO standard related to this Practice is ISO 11431.
Exposure of Non-Metallic Materials
Significant differences exist between the procedures. The ISO
2.2 ISO Standard:
specimensareexposedthroughglassandareelongatedpriorto
ISO 11431 Building Construction—Sealants: Determination
examination for loss of adhesion or cohesion, or both, follow-
of Adhesion/Cohesion Properties After Exposure to Heat
ing exposure.
and Artificial Light Through Glass and to Moisture
1.5 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
3. Terminology
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter- 3.1 Definitions—Definitions of the following terms are
mine the applicability of regulatory limitations prior to use. found in Terminology C717: standard conditions, compound,
1.6 This international standard was developed in accor- cure, sealant, substrate. Definitions of the following terms are
dance with internationally recognized principles on standard- found in Terminology G113: actinic radiation, control
material, file specimen, fluorescent ultraviolet lamps,
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom- irradiance, open flame carbon arc, radiant exposure, sample,
solar radiation-ultraviolet, solar radiation-visible, spectral
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee. power distribution, xenon arc.
2. Referenced Documents
4. Summary of Practice
2.1 ASTM Standards: 4.1 The test sealant may be applied to a variety of types of
C717 Terminology of Building Seals and Sealants
substratesortestedasafreefilm.Theconfigurationdependson
the properties to be evaluated following exposure.At least four
replicates of each sealant being tested are required. After
This practice is under the jurisdiction of ASTM Committee C24 on Building
curing, one replicate of each sealant being tested is retained as
Seals and Sealants and is the direct responsibility of Subcommittee C24.40 on
an unexposed file specimen and three replicates are exposed to
Weathering.
actinicradiation,heat,andmoisture.Attheendoftheexposure
Current edition approved May 1, 2021. Published May 2021. Originally
period, the test sealant is examined for property change in
approved in 1999. Last previous edition approved in 2014 as C1442 – 14. DOI:
10.1520/C1442-14R21.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. 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.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1442 − 14 (2021)
comparison with the unexposed file specimen and the perfor- 5.6 The acceleration factor relating the exposure time in a
mance is compared with that of an exposed control material, if laboratory accelerated test to exposure time outdoors required
used. to produce equivalent degradation is material dependent and
can be significantly different for each material and for different
4.2 It is recommended that a similar material of known
formulations of the same material. Therefore, the acceleration
performance under use conditions (a control) be exposed
factor determined for one material cannot be assumed to be
simultaneously with the test specimen for evaluation of the
applicable to other materials.
performance of the test materials relative to that of the control
5.7 Results of this procedure will depend on the care that is
under the same laboratory exposure conditions. It is preferable
taken to operate the equipment according to Practices G152,
tousetwocontrolmaterials,onewithrelativelypoordurability
G154, and G155. Significant factors include regulation of the
and the other with good durability.
line voltage, freedom from salt or other deposits from water,
temperature control, humidity control, where applicable, con-
5. Significance and Use
dition and age of the burners and filters in xenon arc
5.1 This practice determines the effects of actinic radiation,
equipment, and age of lamps in fluorescent UV equipment.
elevated temperature, and moisture on sealants and their
NOTE 1—Additional information on sources of variability and on
constituents under controlled laboratory artificial weather test
strategies for addressing variability in the design, execution and data
analysis of laboratory accelerated exposure tests is found in Guide G141.
conditions.
5.2 When conducting exposures in devices which use labo-
6. Test Specimens
ratorylightsources,itisimportanttoconsider (1)howwellthe
6.1 The size and configuration of the specimens are deter-
artificial test conditions will reproduce property changes and
mined by the specifications of the test method used to evaluate
failure modes caused by end-use environments on the sealant
the effect of exposure on the specimens. Where practical, it is
being tested and (2) the stability ranking of sealants. Refer to
recommended that specimens be sized to fit the sample holders
Practice G151 for full cautionary guidance regarding labora-
supplied with the apparatus.
tory weathering.
6.2 Some common specimen configurations may include
5.3 Because of differences in the spectral power distribu-
slab, tensile bar, H-block aymar samples, patties, sheets,
tions of the exposure sources (xenon arc, fluorescent UV
drawdowns, preformed joint sealants, prevulcanized elasto-
lamps, and open flame carbon arc), as well as other conditions
meric joint materials, beads, channels, and so forth.
usedinthethreetypesoflaboratoryweatheringtests,including
6.3 Specimens configured for movement during exposure to
temperature, type and amount of moisture, and test cycles,
artificial weathering conditions also may be used.
these three procedures may not result in the same performance
ranking or types of failure modes of sealants. Further, different
6.4 Follow the procedures described in Practice G147 for
exposure durations may be required for testing the weathering
identification and handling of specimens prior to, during and
performance of sealants by the three types of exposures.
after exposure.
Comparisons should not be made of the relative stability of
6.5 When destructive tests are used to evaluate weathering
sealants exposed in the different types of apparatus.
stability, ensure that sufficient unexposed file specimens are
5.4 Variations in results may be expected when operating
retained so that the property of interest can be determined on
conditionsarevariedwithintheacceptedlimitsofthispractice.
unexposed file specimens each time exposed materials are
Therefore, all test results using this practice must be accom-
evaluated.
panied by a report of the specific operating conditions as
required in Section 10. Refer to Practice G151 for detailed
7. Apparatus
information on the caveats applicable to use of results obtained
7.1 Test Chamber—Choice of apparatus and exposure con-
according to this practice.
ditions selected shall be by mutual agreement among the
5.5 No laboratory exposure test can be specified as a total interestedparties.Becausethedifferenttypesofexposuresmay
simulation of actual use conditions in outdoor environments. produce different test results, they cannot be used interchange-
The relative durability of materials in actual use conditions can ably without supporting data that demonstrates equivalency of
vary in different locations because of differences in UV the procedures for the materials tested.The procedures shall be
radiation, time of wetness, relative humidity, temperature, as described in 7.2, 7.3, and 7.4, which are based on test
pollutants, and other factors. Results obtained from these procedures in ASTM and ISO standards and on parameters
laboratory accelerated exposures can be considered as repre- used in round robin tests on sealants.
sentative of actual use exposures only when the degree of rank 7.1.1 The operational fluctuations are allowable deviations
correlationhasbeenestablishedforthespecificmaterialsbeing from the specified set points for irradiance, temperature and
tested and when the failure mode is the same. Exposure of a relative humidity during equilibrium operation. They do not
similar material of known outdoor performance, a control, imply that the user is allowed to program a set point higher or
along with the test specimens provides for evaluation in terms lower than that specified. If the operational fluctuations are
of relative durability under the test conditions, which also greater than the maximum allowable after the equipment has
greatly improves the agreement in test results among different stabilized, discontinue the test and correct the cause of the
laboratories. problem before continuing.
C1442 − 14 (2021)
7.2 ProcedureforExposureinXenonArcLightApparatus— 7.3 Procedure for Exposure in Fluorescent UVApparatus—
Unless otherwise specified, use the following operating condi- Unless otherwise specified, use the following operating condi-
tions and see Practices G151 and G155 for requirements that tions and see Practices G151 and G154 for requirements that
are not given below: are not given below:
7.2.1 The xenon arc shall be used with daylight type filters
7.3.1 Use fluorescent UVA-340 lamps that comply with the
to simulate direct exposure to solar radiation and conform with
spectral power distribution specifications in Practice G154.
the spectral power distribution in Practice G155.
7.3.2 In apparatus with irradiance control, irradiance shall
7.2.2 The irradiance shall be set at a level not less than 0.35
be set at 0.89 W/(m · nm) at 340 nm.
nor greater than 0.51 W/(m · nm) at 340 nm. The maximum
NOTE 4—The irradiance setting is an attempt to provide irradiance
allowable operational fluctuation is 60.02 W/(m · nm). For
similar to that measured in the fluorescent UV apparatus without irradi-
equivalent broadband irradiance levels and maximum allow-
ance control, when operated at a temperature of 60 °C. In previous
able operational fluctuations at 300–400 nm and 300–800 nm,
editions of C1442, the irradiance set point was 0.77 W/(m · nm) at 340
consult the manufacturer of the apparatus.
nm. Due to an error in calibration by one manufacturer, the actual
2 2
irradiance was 0.89 W/(m · nm) when the specific manufacturer’s
7.2.2.1 The irradiance level of 0.51 W/(m · nm) at 340 nm
equipment was set at 0.77 W/(m · nm). Therefore, the correct setting for
is preferred for reasons given in Appendix X1.1. However, to
the recalibrated equipment is 0.89 W/(m · nm). However, for users of
accommodate users who are required to operate the machine at
equipment made by other manufacturers that had been correctly
0.35 W/(m · nm) at 340 nm for other tests carried out
calibrated,runningatthenewsetpointwillresultinachangeintheactual
simultaneously, the lower irradiance level is an option.The test
irradiance of the test. If in doubt, users should consult the manufacturer of
their device for clarification. There can be differences in test results when
duration is specified in terms of radiant exposure and the time
using different irradiance levels. Refer to Appendix X2 for information
is adjusted according to the formula in Annex A1.2 to obtain
regarding the effect of irradiance.
the same radiant exposure at different irradiance levels. See
Appendix X2 for discussion on effect of variation in irradiance 7.3.3 Seal any holes larger than 2 mm in specimens and any
opening larger than 1 mm around irregularly shaped specimens
level.
7.2.3 The default exposure cycle shall be 102 min light only to prevent loss of water vapor. Attach porous specimens to a
solid backing, such as aluminum, that can act as a vapor
followed by a wet period of 18 min light with wetting either by
barrier.
water spray on the front surface or immersion in water. The
water spray temperature is uncontrolled, but is typically 21 6 7.3.4 For specimens that are less than 20 mm thick, includ-
5 °C. It may be lower if ambient water temperature is low and
ing support dimensions, the exposure cycle shall be8hUVat
a holding tank is not used to store purified water. The an uninsulated black panel temperature set at 60 °C followed
recirculated immersion water temperature is typically 40 6 5
by 4 h wetting by condensation at an uninsulated black panel
°C during the test. temperature set at 50 °C. The maximum allowable operational
temperature fluctuation is 62.5 °C.
NOTE 2—For sealants in which moisture has a significant effect on
weathering,thetwotypesofwettingmayproducedifferenttestresultsdue 7.3.5 For spe
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