It is not possible to establish a precise correlation between accelerated and natural weathering because of geographical climatic variations, local weather variation from normal, and local pollutants. This weathering apparatus and procedure are used for comparing the weathering characteristics of bituminous materials against a reference material for which the outdoor weathering characteristics are known. Guide G 141 provides guidance regarding this issue.1.1 This practice describes test conditions and procedures for enclosed carbon-arc exposures conducted according to Practices G 151 and G 153 for bituminous roofing and waterproofing materials that have a minimum softening point of approximately 95°C (200°F) as determined by Test Method D 36. (See also Terminology G 113.)1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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 limitations prior to use.

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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. 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 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.1.1 This practice covers the basic principles and operating procedures for using enclosed 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 enclosed carbon arc light under controlled environmental conditions.1.3 Specimen preparation and evaluation of the results are covered in various 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 ISO 4582.1.4 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 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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4.1 The ability of a plastic material to resist deterioration of its electrical, mechanical, and optical properties caused by exposure to light, heat, and water can be very significant for many applications. This practice is intended to induce property changes associated with end-use conditions, including the effects of sunlight, moisture, and heat. The exposure used in this practice is not intended to simulate the deterioration caused by localized weather phenomena such as atmospheric pollution, biological attack, and saltwater exposure.4.2 Caution—Variation in results can be expected when operating conditions are varied within the accepted limits of this practice; therefore, no reference to the use of this practice shall be made unless accompanied by a report prepared in accordance with Section 9 that describes the specific operating conditions used. Refer to Practice G151 for detailed information on the caveats applicable to use of results obtained in accordance with this practice.NOTE 2: Additional information on sources of variability and on strategies for addressing variability in the design, execution, and data analysis of laboratory-accelerated exposure tests is found in Guide G141.4.2.1 The spectral power distribution of light from an enclosed carbon arc is significantly different from that produced in light and water exposure devices using other carbon-arc configurations or other light sources. The type and rate of degradation and the performance rankings produced by exposures to enclosed carbon arcs can be much different from those produced by exposures to other types of laboratory light sources.4.2.2 Interlaboratory comparisons are valid only when all laboratories use the same type of carbon arc, filters, and exposure conditions4.3 Reproducibility of test results between laboratories has been shown to be good when the stability of materials is evaluated in terms of performance ranking compared to other materials or to a control; therefore, exposure of a similar material of known performance (a control) at the same time as the test materials is strongly recommended.4,5 It is recommended that at least three replicates of each material be exposed to allow for statistical evaluation of results.4.4 Test results will depend upon the care that is taken to operate the equipment in accordance with Practice G153. Significant factors include regulation of line voltage, freedom from salt or other deposits from water, temperature and humidity control, and conditions of the electrodes.1.1 This practice covers specific procedures and test conditions that are applicable for exposure of plastics in enclosed carbon-arc devices conducted in accordance with Practices G151 and G153. This practice also covers the preparation of test specimens, the test conditions suited for plastics, and the evaluation of test results.1.2 This practice does not cover filtered open-flame carbon-arc exposures of plastics, which are covered in Practice D1499. Practice D5031 describes enclosed carbon-arc exposures of paints and related coatings.1.3 The values stated in SI units are to be regarded as standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.NOTE 1: There is no known ISO equivalent to this practice.1.5 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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4.1 The thermal resistance, R, of an insulation is used to describe its thermal performance.4.2 The thermal resistance of an insulation is related to the density and thickness of the insulation. It is desirable to obtain test data on thermal resistances at thicknesses and densities related to the end uses of the product.4.3 In normal use, the thickness of these products range from less than 100 mm (4 in.) to greater than 150 mm (6 in.). Installed densities depend upon the product type, the installed thickness, the installation equipment used, the installation techniques, and the geometry of the insulated space.4.4 Loose-fill insulations provide coverage information using densities selected by manufacturers to represent the product installed densities. Generally, it is necessary to know the product thermal performance at a representative density.4.5 When applicable specifications or codes do not specify the nominal thermal resistance level to be used for comparison purposes, a recommended practice is to use the Rsi (metric) = 2.65 m F/Btu]) label density and thickness for that measurement.4.6 If the density for test purposes is not available from the coverage chart, a test density shall be established by use of applicable specifications and codes or, if none apply, agreement between the requesting body and the testing organization.4.7 Generally, thin sections of these materials are not uniform. Thus, the test thickness must be greater than or equal to the product’s representative thickness if the results are to be consistent and typical of use.NOTE 1: The representative thickness is specific for each product and is determined by running a series of tests in which the density is held constant but the thickness is increased. The representative thickness is defined here as that thickness above which there is no more than a 2 % change in the resistivity of the product. The representative thickness is a function of product blown density. In general, as the density decreases, the representative thickness increases. Fortunately, most products are designed to be blown over a small range of densities. This limited range yields a range of representative thicknesses between 75 to 150 mm (3 to 6 in.) for most products. To simplify the process for this practice, the representative thickness for the C1859 tests is considered 87.5 mm (3 1/2 in). All thermal testing on this product is conducted at a thickness that is greater or equal to the representative thickness.4.7.1 For this practice, the minimum test thickness shall be 87.5 mm (3 1/2 in.). If the test is to represent an installation at a lesser thickness, the installed thickness shall be used.4.8 For purposes of this practice, it is acceptable to estimate the thermal resistance at any thickness from the thermal resistivity obtained from tests on the product at the minimum test thickness (see 4.7.1) and at the density expected for the proposed thickness.4.9 In principle, any of the standard methods for the determination of thermal resistance are suitable for loose-fill products. These include Test Methods C177, C518, C1114, and C1363. This practice was developed in relationship to Test Method C518 specimen size and geometry. For this reason, Test Method C518 is preferred. Test Methods C177, C1114, and C1363 are acceptable but changes to specimen size and geometry are possible.4.10 The thermal resistance of low-density insulations depend upon the direction of heat flow. Unless otherwise specified, tests shall be performed for the maximum heat flow condition, that is, a horizontal specimen with heat flow-up.4.11 Specimens shall be prepared in a manner consistent with the intended installation procedure. Products for pneumatic installation behind netting shall be pneumatically applied (blown) using the manufacturer’s installation instructions and netting specified.1.1 This practice presents a laboratory guide to determine the thermal resistance of pneumatically installed loose-fill building insulations for enclosed applications of the building thermal envelope behind netting at mean temperatures between –10 and 35°C (14 to 95°F).1.2 This practice applies to a wide variety of loose-fill thermal insulation products including but not limited to fibrous glass, rock/slag wool, or cellulosic fiber materials and any other insulation material that can be installed pneumatically. It does not apply to products that change their character after installation either by chemical reaction or the application of binders, adhesives or other materials that are not used in the sample preparation described in this practice, nor does it consider the effects of structures, containments, facings, or air films.1.3 Since this practice is designed for reproducible product comparison, it measures the thermal resistance of an insulation material which has been preconditioned to a relatively dry state. Consideration of changes of thermal performance of a hygroscopic insulation by sorption of water is beyond the scope of this practice.1.4 The sample preparation techniques outlined in this practice do not cover the characterization of loose-fill materials intended for open applications and not intended for spray-applied applications.1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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.

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