ASTM G152-13(2021)
(Practice)Standard Practice for Operating Open Flame Carbon Arc Light Apparatus for Exposure of Nonmetallic Materials
Standard Practice for Operating Open Flame Carbon Arc Light Apparatus for Exposure of Nonmetallic Materials
SIGNIFICANCE AND USE
5.1 The use of this apparatus is intended to induce property changes associated with the end use conditions, including the effects of sunlight, moisture, and heat. These exposures may include a means to introduce moisture to the test specimen. Exposures are not intended to simulate the deterioration caused by localized weather phenomena, such as atmospheric pollution, biological attack, and saltwater exposure. Alternatively, the exposure may simulate the effects of sunlight through window glass. Typically, these exposures would include moisture in the form of humidity.
Note 2: Caution: Refer to Practice G151 for full cautionary guidance applicable to all laboratory weathering devices.
5.2 Variation in results may be expected when operating conditions are varied within the accepted limits of this practice. No reference, therefore, shall be made to results from the use of this practice unless accompanied by a report detailing the specific operating conditions in conformance with Section 10.
5.2.1 It is recommended that a similar material of known performance, a control, be exposed simultaneously with the test specimen to provide a standard for comparative purposes. It is best practice to use control materials known to have relatively poor and good durability. It is recommended that at least three replicates of each material evaluated be exposed in each test to allow for statistical evaluation of results.
SCOPE
1.1 This practice covers the basic principles and operating procedures for using open flame carbon-arc light and water apparatus intended to reproduce the weathering effects that occur when materials are exposed to sunlight (either direct or through window glass) and moisture as rain or dew in actual use. This practice is limited to the procedures for obtaining, measuring, and controlling conditions of exposure. A number of exposure procedures are listed in an appendix; however, this practice does not specify the exposure conditions best suited for the material to be tested.
Note 1: Practice G151 describes performance criteria for all exposure devices that use laboratory light sources. This practice replaces Practice G23, which describes very specific designs for devices used for carbon-arc exposures. The apparatus described in Practice G23 is covered by this practice.
1.2 Test specimens are exposed to filtered open flame carbon arc light under controlled environmental conditions. Different filters are described.
1.3 Specimen preparation and evaluation of the results are covered in methods or specifications for specific materials. General guidance is given in Practice G151 and ISO 4892-1. More specific information about methods for determining the change in properties after exposure and reporting these results is described in Practice D5870.
1.4 The values stated in SI units are to be regarded as the 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.
1.5.1 Should any ozone be generated from the operation of the light source, it shall be carried away from the test specimens and operating personnel by an exhaust system.
1.6 This practice is technically similar to ISO 4892-4.
1.7 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
Relations
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: G152 − 13 (Reapproved 2021)
Standard Practice for
Operating Open Flame Carbon Arc Light Apparatus for
Exposure of Nonmetallic Materials
This standard is issued under the fixed designation G152; 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* 1.7 This practice is technically similar to ISO 4892-4.
1.1 This practice covers the basic principles and operating
1.8 This international standard was developed in accor-
procedures for using open flame carbon-arc light and water
dance with internationally recognized principles on standard-
apparatus intended to reproduce the weathering effects that
ization established in the Decision on Principles for the
occur when materials are exposed to sunlight (either direct or
Development of International Standards, Guides and Recom-
through window glass) and moisture as rain or dew in actual
mendations issued by the World Trade Organization Technical
use. This practice is limited to the procedures for obtaining,
Barriers to Trade (TBT) Committee.
measuring, and controlling conditions of exposure. A number
of exposure procedures are listed in an appendix; however, this
2. Referenced Documents
practice does not specify the exposure conditions best suited
2.1 ASTM Standards:
for the material to be tested.
D3980 Practice for Interlaboratory Testing of Paint and
NOTE 1—Practice G151 describes performance criteria for all exposure 3
Related Materials (Withdrawn 1998)
devices that use laboratory light sources. This practice replaces Practice
D5870 Practice for Calculating Property Retention Index of
G23, which describes very specific designs for devices used for carbon-arc
Plastics
exposures. The apparatus described in Practice G23 is covered by this
practice.
E691 Practice for Conducting an Interlaboratory Study to
Determine the Precision of a Test Method
1.2 Test specimens are exposed to filtered open flame
G23 Practice for Operating Light-Exposure Apparatus
carbon arc light under controlled environmental conditions.
(Carbon-Arc Type) With and Without Water for Exposure
Different filters are described.
of Nonmetallic Materials (Withdrawn 2000)
1.3 Specimen preparation and evaluation of the results are
G113 Terminology Relating to Natural and Artificial Weath-
covered in methods or specifications for specific materials.
ering Tests of Nonmetallic Materials
General guidance is given in Practice G151 and ISO 4892-1.
G151 Practice for Exposing Nonmetallic Materials in Accel-
More specific information about methods for determining the
erated Test Devices that Use Laboratory Light Sources
change in properties after exposure and reporting these results
is described in Practice D5870. 2.2 CIE Standard:
CIE-Publ. No. 85: Recommendations for the Integrated
1.4 The values stated in SI units are to be regarded as the
Irradiance and the Spectral Distribution of Simulated
standard.
Solar Radiation for Testing Purposes
1.5 This standard does not purport to address all of the
2.3 ISO Standards:
safety concerns, if any, associated with its use. It is the
ISO 4892-1 Plastics—Methods of Exposure to Laboratory
responsibility of the user of this standard to establish appro-
Light Sources, Part 1, General Guidance
priate safety, health, and environmental practices and deter-
ISO 4892-4 Plastics—Methods of Exposure to Laboratory
mine the applicability of regulatory limitations prior to use.
Light Sources, Part 4, Open-Flame Carbon Arc Lamp
1.6 Should any ozone be generated from the operation of the
light source, it shall be carried away from the test specimens
and operating personnel by an exhaust system.
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
This practice is under the jurisdiction of ASTM Committee G03 on Weathering Standards volume information, refer to the standard’s Document Summary page on
and Durability and is the direct responsibility of Subcommittee G03.03 on the ASTM website.
Simulated and Controlled Exposure Tests. The last approved version of this historical standard is referenced on
Current edition approved June 1, 2021. Published July 2021. Originally approved www.astm.org.
in 1997. Last previous edition approved in 2013 as G152 – 13. DOI: 10.1520/ Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
G0152-13R21. 4th Floor, New York, NY 10036, http://www.ansi.org.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
G152 − 13 (2021)
TABLE 1 Typical Relative Ultraviolet Spectral Power Distribution
3. Terminology
A,B
of Open-Flame Carbon-Arc with Daylight Filters
3.1 Definitions—The definitions given in Terminology G113
Spectral Bandpass Typical Benchmark Solar
C D,E,F
are applicable to this practice.
Wavelength λ in nm Percent Radiation Percent
3.1.1 As used in this practice, the term sunlight is identical
λ < 290
290 # λ # 320 2.9 5.8
to the terms daylight and solar irradiance, global as they are
320 < λ # 360 20.4 40.0
defined in Terminology G113.
360 < λ # 400 76.7 54.2
A
Data in Table 1 are the irradiance in the given bandpass expressed as a
4. Summary of Practice
percentage of the total irradiance from 290 to 400 nm. Annex A1 states how to
determine relative spectral irradiance.
4.1 Specimens are exposed to repetitive cycles of light and
B
The data in Table 1 is representative and is based on the rectangular integration
moisture under controlled environmental conditions.
of the spectral power distributions of open flame carbon arcs with daylight filters.
4.1.1 Moisture usually is produced by spraying the test There is not enough data available to establish a meaningful specification.
C
For any individual spectral power distribution, the calculated percentage for the
specimen with demineralized/deionized water or by condensa-
bandpasses in Table 1 will sum to 100 %. Test results can be expected to differ
tion of water vapor onto the specimen.
between exposures using open flame carbon arc devices in which the spectral
power distributions differ by as much as that allowed by the tolerances typical for
4.2 The exposure condition may be varied by selection of:
daylight filters. Contact the manufacturer of the carbon-arc devices for specific
4.2.1 Light source filter,
spectral power distribution data for the open flame carbon-arc and filters used.
D
The benchmark solar radiation data is defined in ASTM G177 and is for
4.2.2 The type of moisture exposure,
atmospheric conditions and altitude chosen to maximize the fraction of short
4.2.3 The timing of the light and moisture exposure,
wavelength solar UV. While this data is provided for comparison purposes only, a
4.2.4 The temperature of light exposure, and laboratory accelerated light source with daylight filters to provide a spectrum that
is a close match to this the benchmark solar spectrum.
4.2.5 The timing of a light/dark cycle.
E
Previous versions of this standard used solar radiation data from Table 4 of CIE
Publication number 85. See Appendix X2 for more information comparing the solar
4.3 Comparison of results obtained from specimens exposed
radiation data used in this standard with that for CIE 85, Table 4.
in same model of apparatus should not be made unless
F
For the benchmark solar spectrum, the UV irradiance (290-400 nm) is 9.8 % and
reproducibility has been established among devices for the
the visible irradiance (400-800 nm) is 90.2 % expressed as a percentage of the
total irradiance from 290 to 800 nm. The percentages of UV and visible irradiances
material to be tested.
on samples exposed in open flame carbon-arc devices may vary due to the
4.4 Comparison of results obtained from specimens exposed number and reflectance properties of specimens being exposed. This is based on
measurements in xenon-arc devices but similar measurements have not been
in different models of apparatus should not be made unless
made in open flame carbon-arc devices.
correlation has been established among devices for the material
to be tested.
5. Significance and Use
5.1 The use of this apparatus is intended to induce property
contain a mixture of rare-earth metal salts and have a metal
changes associated with the end use conditions, including the
coating such as copper on the surface. An electric current is
effects of sunlight, moisture, and heat. These exposures may
passed between the carbon rods which burn and give off
include a means to introduce moisture to the test specimen.
ultraviolet, visible, and infrared radiation. The carbon rod pairs
Exposures are not intended to simulate the deterioration caused
are burned in sequence, with one pair burning at any one time.
by localized weather phenomena, such as atmospheric
Use carbon rods recommended by the device manufacturer.
pollution, biological attack, and saltwater exposure.
6.1.1 Filter Types—Radiation emitted by the open flame
Alternatively, the exposure may simulate the effects of sunlight
carbon arc contains significant levels of very short wavelength
through window glass. Typically, these exposures would in-
UV (less than 260 nm) and must be filtered. Two types of glass
clude moisture in the form of humidity.
filters are commonly used. Other filters may be used by mutual
NOTE 2—Caution: Refer to Practice G151 for full cautionary guidance
agreement by the interested parties as long as the filter type is
applicable to all laboratory weathering devices.
reported in conformance with the report section in Practice
5.2 Variation in results may be expected when operating
G151.
conditions are varied within the accepted limits of this practice.
6.1.2 None of these filters changes the spectral power
No reference, therefore, shall be made to results from the use
distribution of the open flame carbon arc to make it match
of this practice unless accompanied by a report detailing the
daylight in the long wavelength UV or the visible light regions
specific operating conditions in conformance with Section 10.
of the spectrum.
5.2.1 It is recommended that a similar material of known
6.1.3 The following factors can affect the spectral power
performance, a control, be exposed simultaneously with the
distribution of open flame carbon arc light sources:
test specimen to provide a standard for comparative purposes.
6.1.3.1 Differences in the composition and thickness of
It is best practice to use control materials known to have
filters can have large effects on the amount of short wavelength
relatively poor and good durability. It is recommended that at
UV radiation transmitted.
least three replicates of each material evaluated be exposed in
6.1.3.2 Aging of filters can result in changes in filter
each test to allow for statistical evaluation of results.
transmission. The aging properties of filters can be influenced
by the composition. Aging of filters can result in a significant
6. Apparatus
reduction in the short wavelength UV emission of a burner.
6.1 Laboratory Light Source—Open flame carbon arc light 6.1.3.3 Accumulation of dirt or other residue on filters can
sources typically use three or four pairs of carbon rods, which affect filter transmission.
G152 − 13 (2021)
TABLE 2 Typical Relative Spectral Power Distribution for Open
data in Table 2 is representative of the spectral irradiance
Flame Carbon Arc With Window Glass Filters (Representative
received by a test specimen mounted in the specimen plane of
Data)
an open flame carbon arc equipped with window glass filters.
Ultraviolet Wavelength Region
6.1.4.3 Spectral Irradiance of Open Flame Carbon arc With
Irradiance as a Percentage of Total Irradiance from 300 to 400 nm
Extended UV filters—Filters that transmit more short wave-
Open Flame Carbon Arc Estimated Window Glass
A B
Bandpass (nm) with Window Glass Filters Filtered Sunlight
length UV are sometimes used to accelerate test results.
250–270 0 % 0 %
Although this type of filter has been specified in many tests
271–290 0 % 0 %
because of historical precedent, they transmit significant radi-
291–300 0 % 0 %
301–320 2.1 % 0.1–1.5 %
ant energy below 300 nm (the typical cut-on wavelength for
321–340 8.1 % 9.4–14.8 %
terrestrial sunlight) and may result in aging processes not
341–360 13.2 % 23.2–23.5 %
occurring outdoors. The spectral irradiance for an open flame
361–380 27.3 % 29.6–32.5 %
381–400 49.3 % 30.9–34.5 %
carbon arc with extended UV filters shall comply with the
requirements of Table 3.
Ultraviolet and Visible Wavelength Region Irradiance as a Percentage of Total
C
Irradiance from 300 to 800 nm
NOTE 4—The most commonly used type of extended UV filters are
C
Irradiance as a Percentage of Total Irradiance from 300 to 800 nm
made from Potash-Lithia glass and are commonly known as Corex D
filters.
Open Flame Carbon Arc Estimated Window Glass
E D
Bandpass (nm) with Window Glass Filters Filtered Sunlight
6.2 Test Chamber—The design of the test chamber may
300–400 22.7–34.1 % 9.0–11.1 %
vary, but it should be constructed from corrosion resistant
401–700 51.1–67.3 % 71.3–73.1 %
*Data from 701 to 800 nm is not shown
material, and in addition to the radiation source, may provide
for means of controlling temperature and relative humidity.
A
Carbon Arc Data—This data are for a typical spectral power distribution for an
When required, provision shall be made for the spraying of
open flame carbons arc with window glass filters. Not enough spectral data is
water on the test specimen or for the formation of condensate
available for meaningful analysis to develop a specification. Subcommittee G03.03
is working to collect sufficient data in order to develop a specification. on the exposed face of the specimen.
B
Sunlight Data—The sunlight data is for global irradiance on a horizontal surface
6.2.1 The radiant source(s) shall be located with respect to
with an air mass of 1.2, column ozone 0.294 atm cm, 30 % relative humidity,
the specimens such that the irradiance at the specimen face
altitude 2100 m (atmospheric pressure of 787.8 mb), and an aerosol represented
by an optical thickness of 0.081 at 300 nm and 0.62 at 400 nm. The range is complies with the requirements in Practice G151.
determined by multiplying solar irradiance by the upper and lower limits for
6.3 Instrument Calibration—To ensure
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