G03.02 - Natural and Environmental Exposure Tests

SIGNIFICANCE AND USE
5.1 As with any accelerated test, the increase in rate of weathering compared to in-service exposure is material dependent. Results from exposures conducted to this practice may provide good rank correlation to results from actual use conditions for one type of material or product. It should not be assumed that this will be true for other materials or products. It is always best to verify the ability of an accelerated exposure test to properly rank the durability of materials with actual use conditions. Guide G141 provides information about using rank correlation.  
5.2 Variation in results may be expected when operating conditions are varied within the accepted limits of this practice. Therefore, no reference shall be made to results from the use of this practice unless accompanied by a report detailing the specific operating conditions in conformance with Report Section 8.  
5.3 The durability of materials in outdoor use can be very different depending on the location of the exposure because of differences in solar radiation, moisture, heat, pollutants, and other factors. Therefore, it cannot be assumed that results from exposure in a single location will be useful for determining durability ranking of materials in a different location.  
5.4 It is recommended that at least one control material be exposed with each test. The control material should be of similar composition and construction and be chosen so that its failure modes are the same as that of the material being tested. It is preferable to use two control materials, one with relatively good durability, and one with relatively poor durability. If control materials are included as part of the test, they shall be used for the purpose of comparing the performance of the test materials relative to the controls.
SCOPE
1.1 This practice covers the basic principles and operating procedures for using outdoor glass-covered exposure apparatus with air circulation. This practice is limited to the procedures for obtaining, measuring and controlling conditions of exposure. A number of exposure procedures are listed in Appendix X1; however, this practice does not specify the exposure conditions best suited for the material to be tested.  
1.2 For direct weathering exposures, refer to Practice G7. For exposures behind glass without air circulation, refer to Practice G24.  
1.3 Test specimens are exposed to solar radiation filtered through glass under partially controlled environmental test conditions. Different glass types and operating parameters are described.  
1.4 Specimen preparation and evaluation of the results are covered in ASTM methods or specifications for specific materials. More specific information for determining the change in properties after exposure and reporting these results is described in Practices D5870, D2244 and Test Method D523.  
1.5 The values stated in SI units are to be regarded as standard.  
1.6 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.  
1.7 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.

SIGNIFICANCE AND USE
4.1 Results obtained from this practice can be used to compare the relative durability of materials subjected to the specific test cycle used. No accelerated test can be specified as a perfect simulation of natural or field exposures. Results obtained from this practice can be considered as representative of natural weathering only when a sufficient magnitude of mathematical correlation exists between exposures.  
4.2 The acceleration factor relating the rate of degradation in this accelerated exposure to the rate of degradation in a natural weathering exposure varies with the type and formulation of the material. Each material and formulation may respond differently to the increased level of irradiance and differences in temperature and humidity. Thus an acceleration factor determined for one material may not be applicable to other materials. For this reason, the use of a single acceleration factor is not recommended. Also, a different acceleration factor may be obtained by using different mirror types and configurations. Because of variability in test results for both accelerated and natural weathering exposures, results from a sufficient number of tests must be obtained to determine an acceleration factor for a material. Further, the acceleration factor is applicable to only one exposure location because results from natural weathering will vary due to seasonal or annual differences in climatic factors.  
4.3 The relative durability of materials determined by this practice can be used to determine the relative durability of the materials exposed under natural weathering conditions provided the materials have similar acceleration factors. However, even if results from a specific accelerated test condition are found to be useful for comparing the durability of materials exposed in a particular exterior location, it cannot be assumed that they will be useful for determining the relative durability for a different location. The relative durability of materials in n...
SCOPE
1.1 Linear Fresnel reflector concentrators using the sun as source are utilized in the accelerated outdoor exposure testing of materials.  
1.2 This practice covers a procedure for performing accelerated outdoor exposure testing of materials using a linear Fresnel reflector, accelerated outdoor weathering, test machine. The apparatus (see Fig. 1 and Fig. 2) and guidelines are described herein to minimize the variables encountered during outdoor accelerated exposure testing.    
1.3 This practice does not specify the exposure conditions best suited for the materials to be tested but is limited to the method of obtaining, measuring, and controlling the procedures and certain conditions of the exposure. Sample preparation, test conditions, and evaluation of results are covered in existing methods or specifications for specific materials.  
1.4 The linear Fresnel reflector accelerated outdoor exposure test apparatus described may be suitable for the determination of the relative durability of materials when these materials are exposed to concentrated sunlight, heat, and moisture.  
1.5 This practice establishes uniform sample mounting and in-test maintenance procedures. Also included in the practice are standard provisions for maintenance of the machine and linear Fresnel reflector mirrors to ensure cleanliness and durability.  
1.6 This practice shall apply to specimens whose size meets the dimensions of the target board as described in 8.2.  
1.7 For test machines currently in use, this practice is not recommended for specimens exceeding 13 mm (1/2 in.) in thickness because of specimen cooling.  
1.8 Values stated in SI units are to be regarded as the standard. The inch-pound units in parentheses are provided for information only.  
1.9 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...

SIGNIFICANCE AND USE
4.1 Since solar radiation, air temperature, relative humidity, and the amount and kind of atmospheric contaminants vary continuously, results from exposures based on elapsed time will sometimes differ. The variations in the results will usually be reduced by timing the exposures in terms of:  
4.1.1 One or more environmental parameters such as solar radiant exposure, or  
4.1.2 A predefined property change of a weathering reference specimen with known performance.  
4.2 Variations in temperature, moisture, and atmospheric contaminants can have a significant effect on the degradation caused by solar radiation. In addition, exposures conducted at different times of the year can cause large differences in the rate of degradation. Different materials generally have different sensitivities to heat, moisture, and atmospheric contaminants, and this could explain differences in rankings of specimens exposed to equivalent solar radiant exposure when other environmental conditions vary.  
4.3 Since the method of mounting has an influence on the temperature and other parameters during exposure of the specimen, there shall be agreement between contractual parties as to the method of mounting the specimen for the particular exposure test under consideration.  
4.4 There are differences among various single strength window glasses in their transmittance in the 300 to 350 nm region. For example, at 320 nm, the percent transmittance for seven different lots of single strength window glass ranged from 8.4 to 26.8 %. At 380 nm, the percent transmittance ranged from 84.9 % to 88.1 %.5  
4.5 Differences in UV transmittance between different lots of glass generally continue even after solarization. The largest differences among window glasses in UV transmittance are in the spectral range of 300 to 320 nm.  
4.6 This practice is best used to compare the relative performance of materials tested at the same time behind the same lot of glass. Because of variability between lots of g...
SCOPE
1.1 This practice describes procedures for conducting exposures of various materials to daylight filtered through glass in passively ventilated and non-vented enclosures. For exposures in under glass enclosures with forced air circulation, refer to Practice G201.  
1.1.1 This practice is not intended for corrosion testing of bare metals.  
1.2 For direct exposures, refer to Practice G7.  
1.3 This practice is limited to the method of conducting the exposures. The preparation of test specimens and evaluation of results are covered in various standards for the specific materials.  
1.4 Exposure conducted according to this practice can use two types of exposure cabinets.  
1.4.1 Type A—A cabinet that allows passive ventilation of specimens being exposed behind glass.  
1.4.2 Type B—Enclosed cabinet with exterior painted black that does not provide for ventilation of specimens exposed behind glass. Exposures conducted using a Type B cabinet are typically referred to as “black box under glass exposures.”  
1.5 Type A exposures of this practice are technically similar to Method B of ISO 877-2.  
1.6 Units—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.  
1.7 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.  
1.8 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.

SIGNIFICANCE AND USE
4.1 The relative durability of materials in natural exposures can be very different depending on the location of the exposure because of differences in ultraviolet (UV) radiation, relative humidity, time of wetness, temperature, wet-dry cycling, freeze-thaw cycling, pollutants, and other factors. Therefore, it cannot be assumed that results from one exposure in a single location will be useful for determining relative durability in a different location. Exposures in several locations with different climates which represent a broad range of anticipated service conditions are recommended.  
4.2 Because of year-to-year climatological variations, results from a single exposure test cannot be used to predict the absolute rate at which a material degrades. Several exposures, repeated over several years are needed to get a representative test result for a given location.  
4.3 Solar UV radiation varies considerably as a function of time of year. This can cause large differences in the apparent rate of degradation in many materials. Comparing results for materials exposed for short periods (less than one year) is not recommended unless materials are exposed at the same time in the same location.  
4.4 The duration of natural weathering tests is often based on time (24 months for example). The variability between different exposures can be reduced by using a duration based on total solar or solar UV radiant exposure. Solar UV measurements are typically made using instruments which record broadband UV (for example, 295 to 385 nm), as described in 7.2.4. An inherent limitation in timing a weathering test based solely on solar-radiation measurements is that temperature and moisture may also influence the rate or type of degradation.  
4.5 The design of the exposure rack, the location of the specimen on the exposure rack, and the type, color, and emissivity of adjacent specimens can affect specimen temperature and time of wetness. In order to minimize variability caused by t...
SCOPE
1.1 This practice covers procedures to be followed for direct exposure of materials to the environment. Typically, this testing is performed on exposure racks tilted at a commonly-used tilt angle from the horizontal (such as 5 or 45 degrees) and facing the equator. Other exposure orientations can be used.  
1.2 This practice is not intended for the corrosion testing of bare metals, or for testing behind glass.  
1.2.1 For corrosion testing, refer to Practice G50  
1.2.2 For exposures behind glass, refer to Practice G24  
1.3 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.  
1.4 This practice is technically equivalent to the parts of ISO 877-1 and -2 that describe direct exposures of specimens to the environment.  
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.

SCOPE
1.1 This specification provides specific information for the manufacturing and use of metal black and white panel temperature devices to measure temperatures that estimate highest maximum (black) and lowest maximum (white) temperatures of coated metal specimens during natural weathering tests.  
1.1.1 The construction of a black or white panel has a significant effect on the indicated temperature. This standard describes a robust construction from the panels investigated, which has been shown to provide the highest, most consistent temperatures when compared side-by-side with other black panel constructions.  
1.2 This specification includes details on design requirements and quantitative measurement techniques, which will lead to the proper selection of materials and use for black and white panel temperature sensors.  
1.3 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 requirements prior to use.
Note 1: There is no equivalent ISO standard describing the selection and use of black panel sensors for natural weathering tests.  
1.4 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.

SIGNIFICANCE AND USE
4.1 Results obtained from this practice can be used to compare the relative durability of materials subjected to the specific test cycle used. Results obtained from this practice can be considered as representative of natural weathering only when the degree of comparative performance has been established for the specific materials being tested.  
4.2 The acceleration factor relating the rate of degradation in this accelerated exposure to the rate of degradation in a natural weathering exposure varies with the type and formulation of the material. Each material and formulation may respond differently to the increased level of irradiance and differences in temperature and humidity. Thus an acceleration factor determined for one material may not be applicable to other materials. For this reason, the use of a single acceleration factor is not recommended. Also, a different acceleration factor may be obtained by using different mirror types and configurations. Because of variability in test results for both accelerated and natural weathering exposures, results from a sufficient number of tests must be obtained to determine an acceleration factor for a material. Further, the acceleration factor is applicable to only one exposure location because results from natural weathering will vary due to seasonal or annual differences in climatic factors.  
4.3 The relative durability of materials determined by this practice can be used to determine the relative durability of the materials exposed under natural weathering conditions provided the materials have similar acceleration factors. However, even if results from a specific accelerated test condition are found to be useful for comparing the durability of materials exposed in a particular exterior location, it cannot be assumed that they will be useful for determining the relative durability for a different location. The relative durability of materials in natural weathering exposure can be very different depending on the loc...
SCOPE
1.1 Fresnel-reflecting concentrators using the sun as source are utilized in the accelerated outdoor exposure testing of materials.  
1.2 This practice covers a procedure for performing accelerated outdoor exposure testing of materials using a Fresnel-reflector accelerated outdoor weathering test machine. The apparatus (see Fig. 1 and Fig. 2) and guidelines are described herein to minimize the variables encountered during outdoor accelerated exposure testing.    
1.3 This practice does not specify the exposure conditions best suited for the materials to be tested but is limited to the method of obtaining, measuring, and controlling the procedures and certain conditions of the exposure. Sample preparation, test conditions, and evaluation of results are covered in existing methods or specifications for specific materials.  
1.4 The Fresnel-reflector accelerated outdoor exposure test machines described may be suitable for the determination of the relative durability of materials exposed to sunlight, heat, and moisture, provided the mechanisms of chemical or physical change, or both, which control the acceleration factors for the materials do not differ significantly.  
1.5 This practice establishes uniform sample mounting and in-test maintenance procedures. Also included in the practice are standard provisions for maintenance of the machine and Fresnel-reflector mirrors to ensure cleanliness and durability.  
1.6 This practice shall apply to specimens whose size meets the dimensions of the target board as described in 8.2.  
1.7 For test machines currently in use, this practice may not apply to specimens exceeding 13 mm (1/2 in.) in thickness because cooling may be questionable.  
1.8 Values stated in SI units are to be regarded as the standard. The inch-pound units in parentheses are provided for information only.  
1.9 This standard does not purport to address all of the safety concerns, if any, associated with it...

SIGNIFICANCE AND USE
5.1 As with any accelerated test, the increase in rate of weathering compared to in-service exposure is material dependent. Results from exposures conducted to this practice may provide good rank correlation to results from actual use conditions for one type of material or product. It should not be assumed that this will be true for other materials or products. It is always best to verify the ability of an accelerated exposure test to properly rank the durability of materials with actual use conditions. Guide G141 provides information about using rank correlation.  
5.2 Variation in results may be expected when operating conditions are varied within the accepted limits of this practice. Therefore, no reference shall be made to results from the use of this practice unless accompanied by a report detailing the specific operating conditions in conformance with Report Section 8.  
5.3 The durability of materials in outdoor use can be very different depending on the location of the exposure because of differences in solar radiation, moisture, heat, pollutants, and other factors. Therefore, it cannot be assumed that results from exposure in a single location will be useful for determining durability ranking of materials in a different location.  
5.4 It is strongly recommended that at least one control material be exposed with each test. The control material should be of similar composition and construction and be chosen so that its failure modes are the same as that of the material being tested. It is preferable to use two control materials, one with relatively good durability, and one with relatively poor durability. If control materials are included as part of the test, they shall be used for the purpose of comparing the performance of the test materials relative to the controls.
SCOPE
1.1 This practice covers the basic principles and operating procedures for using outdoor glass-covered exposure apparatus with air circulation. This practice is limited to the procedures for obtaining, measuring and controlling conditions of exposure. A number of exposure procedures are listed in Appendix X1; however, this practice does not specify the exposure conditions best suited for the material to be tested.  
1.2 For direct weathering exposures, refer to Practice G7. For exposures behind glass without air circulation, refer to Practice G24.  
1.3 Test specimens are exposed to solar radiation filtered through glass under partially controlled environmental test conditions. Different glass types and operating parameters are described.  
1.4 Specimen preparation and evaluation of the results are covered in ASTM methods or specifications for specific materials. More specific information for determining the change in properties after exposure and reporting these results is described in Practices D5870, D2244 and Test Method D523.  
1.5 The values stated in SI units are to be regarded as standard.  
1.6 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.

SIGNIFICANCE AND USE
4.1 The relative durability of materials in natural exposures can be very different depending on the location of the exposure because of differences in ultraviolet (UV) radiation, time of wetness, temperature, pollutants, and other factors. Therefore, it cannot be assumed that results from one exposure in a single location will be useful for determining relative durability in a different location. Exposures in several locations with different climates which represent a broad range of anticipated service conditions are recommended.  
4.2 Because of year-to-year climatological variations, results from a single exposure test cannot be used to predict the absolute rate at which a material degrades. Several years of repeat exposures are needed to get an “average” test result for a given location.  
4.3 Solar ultraviolet radiation varies considerably as a function of time of year. This can cause large differences in the apparent rate of degradation in many polymers. Comparing results for materials exposed for short periods (less than one year) is not recommended unless materials are exposed at the same time in the same location.  
4.4 Defining exposure periods in terms of total solar or solar-ultraviolet radiant energy can reduce variability in results from separate exposures. Solar ultraviolet measurements are typically made using instruments which record broadband UV (for example, 295 to 385 nm) or narrow band UV, as described in 7.2.4 and 7.2.5. An inherent limitation in solar-radiation measurements is that they do not reflect the effects of temperature and moisture, which may also influence the rate or type of degradation.  
4.5 The design of the exposure rack, the location of the specimen on the exposure rack, and the type or color of adjacent specimens can affect specimen temperature and time of wetness. In order to minimize variability caused by these factors, it is recommended that test specimens, control specimens, and any applicable weathering reference mat...
SCOPE
1.1 This practice covers procedures to be followed for direct exposure of nonmetallic materials to the environment. When originators of a weathering test have the actual exposure conducted by a separate agency, the specific conditions for the exposure of test and control specimens must be clearly defined and mutually agreed upon between all parties.  
1.2 For exposures behind glass, refer to Practice G24.  
1.3 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.  
1.4 This practice is technically equivalent to the parts of ISO 877 that describe direct exposures of specimens to the environment.  
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 and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 Since solar radiation, air temperature, relative humidity, and the amount and kind of atmospheric contaminants vary continuously, results from exposures based on elapsed time may differ. The variations in the results may be minimized by timing the exposures in terms of:  
4.1.1 One or more environmental parameters such as solar radiant exposure, or  
4.1.2 A predefined property change of a weathering reference specimen with known performance.  
4.2 Variations in temperature, moisture and atmospheric contaminants can have a significant effect on the degradation caused by solar radiation. In addition, exposures conducted at different times of the year can cause large differences in rate of degradation. Different materials may have different sensitivities to heat, moisture, and atmospheric contaminants, which may explain differences in rankings of specimens exposed to equivalent solar radiant exposure when other environmental conditions vary.  
4.3 Since the method of mounting may influence the temperature and other parameters during exposure of the specimen, there should be a mutual understanding as to the method of mounting the specimen for the particular exposure test under consideration.  
4.4 There can be large differences among various single strength window glasses in their transmittance in the 300 to 350 nm region. For example, at 320 nm, the percent transmittance for seven different lots of single strength window glass ranged from 8.4 to 26.8 %. At 380 nm, the percent transmittance ranged from 84.9 % to 88.1 %.6  
4.5 Differences in UV transmittance between different lots of glass persist after solarization. The largest differences among window glasses in UV transmittance are in the spectral range of 300 to 320 nm.  
4.6 This practice is best used to compare the relative performance of materials tested at the same time behind the same lot of glass. Because of variability between lots of glass and between exposures conducted at different times of th...
SCOPE
1.1 This practice evaluates the resistance of nonmetallic materials to solar radiation filtered through glass in passively ventilated and non-vented enclosures. For exposures in under glass enclosures with forced air circulation, refer to Practice G201.  
1.2 For direct exposures, refer to Practice G7.  
1.3 This practice is limited to the method of conducting the exposures. The preparation of test specimens and evaluation of results are covered in various standards for the specific materials.  
1.4 Exposure conducted according to this practice can use two types of exposure cabinets.  
1.4.1 Type A—A cabinet that allows passive ventilation of specimens being exposed behind glass.  
1.4.2 Type B—Enclosed cabinet with exterior painted black that does not provide for ventilation of specimens exposed behind glass. Exposures conducted using a Type B cabinet are typically referred to as “black box under glass exposures.”  
1.5 Type A exposures of this practice are technically similar to Method B of ISO 877-2.  
1.6 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.  
1.7 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.

SCOPE
1.1 This specification provides specific information for the manufacturing and use of metal black and white panel temperature devices to measure temperatures that estimate highest maximum (black) and lowest maximum (white) temperatures of coated metal specimens during natural weathering tests.
1.1.1 The construction of a black or white panel has a significant effect on the indicated temperature. This standard describes a robust construction from the panels investigated, which has been shown to provide the highest, most consistent temperatures when compared side-by-side with other black panel constructions.
1.2 This specification includes details on design requirements and quantitative measurement techniques, which will lead to the proper selection of materials and use for black and white panel temperature sensors.
1.3 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 requirements prior to use.
Note 1—There is no equivalent ISO standard describing the selection and use of black panel sensors for natural weathering tests.

SIGNIFICANCE AND USE
The relative durability of materials in natural exposures can be very different depending on the location of the exposure because of differences in ultraviolet (UV) radiation, time of wetness, temperature, pollutants, and other factors. Therefore, it cannot be assumed that results from one exposure in a single location will be useful for determining relative durability in a different location. Exposures in several locations with different climates which represent a broad range of anticipated service conditions are recommended.
Because of year-to-year climatological variations, results from a single exposure test cannot be used to predict the absolute rate at which a material degrades. Several years of repeat exposures are needed to get an “average” test result for a given location.
Solar ultraviolet radiation varies considerably as a function of time of year. This can cause large differences in the apparent rate of degradation in many polymers. Comparing results for materials exposed for short periods (less than one year) is not recommended unless materials are exposed at the same time in the same location.
Defining exposure periods in terms of total solar or solar-ultraviolet radiant energy can reduce variability in results from separate exposures. Solar ultraviolet measurements are typically made using instruments which record broadband UV (for example, 295 to 385 nm) or narrow band UV, as described in 7.2.4 and 7.2.5. An inherent limitation in solar-radiation measurements is that they do not reflect the effects of temperature and moisture, which may also influence the rate or type of degradation.
The design of the exposure rack, the location of the specimen on the exposure rack, and the type or color of adjacent specimens can affect specimen temperature and time of wetness. In order to minimize variability caused by these factors, it is recommended that test specimens, control specimens, and any applicable weathering reference material be placed on a sing...
SCOPE
1.1 This practice covers procedures to be followed for direct exposure of nonmetallic materials to the environment. When originators of a weathering test have the actual exposure conducted by a separate agency, the specific conditions for the exposure of test and control specimens must be clearly defined and mutually agreed upon between all parties.
1.2 For exposures behind glass, refer to Practice G24.
1.3 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.
1.4 This practice is technically equivalent to the parts of ISO 877 that describe direct exposures of specimens to the environment.
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 and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
Results obtained from this practice can be used to compare the relative durability of materials subjected to the specific test cycle used. No accelerated exposure test can be specified as a total simulation of natural or field exposures. Results obtained from this practice can be considered as representative of natural or field exposures only when the degree of comparative performance has been established for the specific materials being tested.
The relative durability of materials in natural or field exposure can be very different depending on the location of the exposure because of differences in UV radiation, time of wetness, temperature, pollutants, and other factors. Therefore, even if results from a specific accelerated test condition are found to be useful for comparing the relative durability of materials exposed in a particular exterior location, it cannot be assumed that they will be useful for determining relative durability for a different location.
The use of a single acceleration factor relating the rate of degradation in this accelerated exposure to the rate of degradation in a conventional exterior exposure is not recommended because the acceleration factor varies with the type and formulation of the material. Each material and formulation may respond differently to the increased level of irradiance and differences in temperature and humidity. Thus an acceleration factor determined for one material may not be applicable to other materials. Because of variability in test results under both accelerated and conventional exterior exposures results from a sufficient number of tests must be obtained to determine an acceleration factor for a material. Further, the acceleration factor is applicable to only one exterior exposure location because results from conventional exterior exposures can vary due to seasonal or annual differences in important climatic factors.
Variations in results may be expected when operating conditions vary within the limits o...
SCOPE
1.1 Fresnel-reflecting concentrators using the sun as source are utilized in the accelerated outdoor exposure testing of nonmetallic materials.
1.2 This practice covers a procedure for performing accelerated outdoor exposure testing of nonmetallic materials using a Fresnel-reflector accelerated outdoor weathering test machine. The apparatus (see Fig. 1 and Fig. 2) and guidelines are described herein to minimize the variables encountered during outdoor accelerated exposure testing.
1.3 This practice does not specify the exposure conditions best suited for the materials to be tested but is limited to the method of obtaining, measuring, and controlling the procedures and certain conditions of the exposure. Sample preparation, test conditions, and evaluation of results are covered in existing methods or specifications for specific materials.
1.4 The Fresnel-reflector accelerated outdoor exposure test machines described may be suitable for the determination of the relative durability of materials exposed to sunlight, heat, and moisture, provided the mechanisms of chemical or physical change, or both, which control the rates of acceleration factors for the materials do not differ significantly.
1.5 This practice establishes uniform sample mounting and in-test maintenance procedures. Also included in the practice are standard provisions for maintenance of the machine and Fresnel-reflector mirrors to ensure cleanliness and durability.
1.6 This practice shall apply to specimens whose size meets the dimensions of the target board as described in 8.2.
1.7 For test machines currently in use, this practice may not apply to specimens exceeding 13 mm (1/2 in.) in thickness because cooling may be questionable.
1.8 Values stated in SI units are to be regarded as the standard. The inch-pound units in parentheses are provided for information only.
1.9 This standard does not purport to address all of the safety concerns, if ...

SIGNIFICANCE AND USE
As with any accelerated test, the increase in rate of weathering compared to in-service exposure is material dependent. Results from exposures conducted to this practice may provide good rank correlation to results from actual use conditions for one type of material or product. It should not be assumed that this will be true for other materials or products. It is always best to verify the ability of an accelerated exposure test to properly rank the durability of materials with actual use conditions. Guide G141 provides information about using rank correlation.
Variation in results may be expected when operating conditions are varied within the accepted limits of this practice. Therefore, no reference shall be made to results from the use of this practice unless accompanied by a report detailing the specific operating conditions in conformance with Report Section 8.
The durability of materials in outdoor use can be very different depending on the location of the exposure because of differences in solar radiation, moisture, heat, pollutants, and other factors. Therefore, it cannot be assumed that results from exposure in a single location will be useful for determining durability ranking of materials in a different location.
It is strongly recommended that at least one control material be exposed with each test. The control material should be of similar composition and construction and be chosen so that its failure modes are the same as that of the material being tested. It is preferable to use two control materials, one with relatively good durability, and one with relatively poor durability. If control materials are included as part of the test, they shall be used for the purpose of comparing the performance of the test materials relative to the controls.
SCOPE
1.1 This practice covers the basic principles and operating procedures for using outdoor glass-covered exposure apparatus with air circulation. This practice is limited to the procedures for obtaining, measuring and controlling conditions of exposure. A number of exposure procedures are listed in Appendix X1; however, this practice does not specify the exposure conditions best suited for the material to be tested.
1.2 For direct weathering exposures, refer to Practice G7. For exposures behind glass without air circulation, refer to Practice G24.
1.3 Test specimens are exposed to solar radiation filtered through glass under partially controlled environmental test conditions. Different glass types and operating parameters are described.
1.4 Specimen preparation and evaluation of the results are covered in ASTM methods or specifications for specific materials. More specific information for determining the change in properties after exposure and reporting these results is described in Practices D5870, D2244 and Test Method D523.
1.5 The values stated in SI units are to be regarded as standard.
1.6 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.

SCOPE
1.1 Fresnel-reflecting concentrators using the sun as source are utilized in the accelerated outdoor exposure testing of nonmetallic materials.
1.2 This practice covers a procedure for performing accelerated outdoor exposure testing of nonmetallic materials using a Fresnel-reflector accelerated outdoor weathering test machine. The apparatus (see and ) and guidelines are described herein to minimize the variables encountered during outdoor accelerated exposure testing.
1.3 This practice does not specify the exposure conditions best suited for the materials to be tested but is limited to the method of obtaining, measuring, and controlling the procedures and certain conditions of the exposure. Sample preparation, test conditions, and evaluation of results are covered in existing methods or specifications for specific materials.
1.4 The Fresnel-reflector accelerated outdoor exposure test machines described may be suitable for the determination of the relative durability of materials exposed to sunlight, heat, and moisture, provided the mechanisms of chemical or physical change, or both, which control the rates of acceleration factors for the materials do not differ significantly.
1.5 This practice establishes uniform sample mounting and in-test maintenance procedures. Also included in the practice are standard provisions for maintenance of the machine and Fresnel-reflector mirrors to ensure cleanliness and durability.
1.6 This practice shall apply to specimens whose size meets the dimensions of the target board as described in .
1.7 For test machines currently in use, this practice may not apply to specimens exceeding 13 mm (1/2 in.) in thickness because cooling may be questionable.
1.8 Values stated in SI units are to be regarded as the standard. The inch-pound units in parentheses are provided for information only.
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.

SCOPE
1.1 This practice covers procedures to be followed for direct exposure of nonmetallic materials to the environment. When originators of a weathering test have the actual exposure conducted by a separate agency, the specific conditions for the exposure of test and control specimens should be clearly defined and mutually agreed upon between all parties.  
1.2 For exposures behind glass, refer to Practice G 24.  
1.3 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.  
1.4 This practice is technically equivalent to the parts of ISO 877 that describe direct exposures of specimens to the environment.  
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 and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 This practice evaluates the resistance of nonmetallic materials to solar radiation filtered through glass.
1.2 For direct exposures, refer to Practice G 7.
1.3 This practice is limited to the method of conducting the exposures. The preparation of test specimens and evaluation of results are covered in various standards for the specific materials.
1.4 Exposure conducted according to this practice can use two types of exposure cabinets.
1.4.1 Type AA cabinet that allows passive ventilation of specimens being exposed behind glass.
1.4.2 Type BEnclosed cabinet with exterior painted black that allows no ventilation of specimens exposed behind glass. Exposures conducted using a Type B cabinet are typically referred to as "black box under glass exposures."
1.5 Type A exposures of this practice are technically similar to Method B of ISO 877.
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.

SCOPE
1.1 This specification provides specific information for the manufacturing and use of metal black and white panel temperature devices to measure temperatures that estimate highest maximum (black) and lowest maximum (white) temperatures of coated metal specimens during natural weathering tests.
1.1.1 The construction of a black or white panel has a significant effect on the indicated temperature. This standard describes a robust construction from the panels investigated, which has been shown to provide the highest, most consistent temperatures when compared side-by-side with other black panel constructions.
1.2 This specification includes details on design requirements and quantitative measurement techniques, which will lead to the proper selection of materials and use for black and white panel temperature sensors.
1.3 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 requirements prior to use.
Note 1—There is no equivalent ISO standard describing the selection and use of black panel sensors for natural weathering tests.

SCOPE
1.1 Fresnel-reflecting concentrators employing the sun as source are utilized in the accelerated outdoor exposure testing of nonmetallic materials.
1.2 This practice covers a procedure for performing accelerated outdoor exposure testing of nonmetallic materials using a Fresnel-reflector accelerated outdoor weathering test machine. The apparatus (see Figs. 1a and 1b) and guidelines are described herein to minimize the variables encountered during outdoor accelerated exposure testing.
1.3 This practice does not specify the exposure conditions best suited for the materials to be tested but is limited to the method of obtaining, measuring, and controlling the procedures and certain conditions of the exposure. Sample preparation, test conditions, and evaluation of results are covered in existing methods or specifications for specific materials.
1.4 The Fresnel-reflector accelerated outdoor exposure test machines described may be suitable for the determination of the relative durability of materials exposed to sunlight, heat, and moisture, provided the mechanisms of chemical or physical change, or both, which control the rates of acceleration factors for the materials do not differ significantly.
1.5 This practice establishes uniform sample mounting and in-test maintenance procedures. Also included in the practice are standard provisions for maintenance of the machine and Fresnel-reflector mirrors to ensure cleanliness and durability.
1.6 This practice shall apply to specimens whose size meets the dimensions of the target board as described in 8.2.
1.7 For test machines currently in use, this practice may not apply to specimens exceeding 13 mm ( 1/2 in.) in thickness because cooling may be questionable.
1.8 Values stated in SI units are to be regarded as the standard. The inch-pound units in parentheses are provided for information only.
1.9 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.

SCOPE
1.1 This practice covers procedures to be followed for direct exposure of nonmetallic materials to the environment. When originators of a weathering test have the actual exposure conducted by a separate agency, the specific conditions for the exposure of test and control specimens should be clearly defined and mutually agreed upon between all parties.  
1.2 For exposures behind glass, refer to Practice G 24.  
1.3 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.  
1.4 This practice is technically equivalent to the parts of ISO 877 that describe direct exposures of specimens to the environment.  
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 and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 This practice evaluates the resistance of nonmetallic materials to solar radiation filtered through glass.  
1.2 This practice is limited to the method of conducting the exposures. The preparation of test specimens and evaluation of results are covered in various standards for the specific materials.  
1.3 This practice includes two methods:  
1.3.1 Method A -Continuous exposure under glass in a cabinet with passive ventilation.  
1.3.2 Method B -Continuous exposure under glass in enclosed black-painted cabinet (black box under glass).  
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 and health practices and determine the applicability of regulatory limitations prior to use.