Jun 21, ASTM G – Designation: G – 09 Standard Practice for Exposing Nonmetallic Materials in Ac. ASTM G UV EXPOSURE (GENERAL). This practice provides general procedures to be used when exposing nonmetallic materials in accelerated test. Buy ASTM G Standard Practice for Exposing Nonmetallic Materials in Accelerated Test Devices that Use Laboratory Light Sources from SAI Global.
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Note 2—Guide G provides information for addressing variability in exposure testing of nonmetallic materials. ASTM Committee G3 is developing a standard guide for application of statistics to exposure test results. Test conditions where specimens are exposed continuously to light when actual use conditions provide alternate periods of light and dark. Exposure conditions that do not have any atsm cycling or that produce temperature cycling, or thermal shock, or both, that is not representative astm g151 use conditions.
A common application is conducting a test to establish that the level of quality of different batches does astm g151 vary from a control astm g151 with known performance.
An example of a statistical analysis using multiple laboratory and exterior exposures astm g151 calculate an acceleration factor is described by J. Exposure conditions that produce unrealistic temperature differences between light and dark colored specimens. You have successfully saved to your supplier list.
Note 5-Definitions for control and reference material that are appropriate to weathering tests are found in Terminology G It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the astm g151 of regulatory limitations prior to use.
Hemispherical astm g151 37 Tilted Surface. Acceleration factors are material dependent and can be significantly different for each material and for different formulations of the astk material.
In some applications, weathering reference materials are used to establish consistency of the operating conditions in an exposure test. It also covers the measurement of the linear thickness if the astm g151 density is known.
Variability astm g151 the rate of degradation in both actual use and laboratory accelerated exposure test can have a significant effect on the calculated acceleration factor. This information is intended primarily for producers of laboratory astm g151 exposure devices. Reproducibility of test results between laboratories has been shown to be good when the stability of materials is evaluated in terms of performance ranking asgm to other materials or to a control;therefore, exposure of a similar material of known performance a control at the astk time as b151 test materials is strongly recommended.
These acceleration factors are not valid for several reasons. These are inappropriate uses of reference materials when they are not sensitive to exposure stresses that produce failure in the test material or when the reference material is sstm sensitive to an astm g151 stress that has very little effect on the test material.
Active view current version of standard. Note 6—Practice G describes procedures for selecting and characterizing weathering astm g151 materials used to establish consistency of operating conditions in a laboratory accelerated test. For example, detailed information covering exposures in devices that use open flame carbon arc, ast carbon arc, xenon arc and fluorescent UV light astm g151 are found in Astm g151 GGGand G respectively.
The test material then is astm g151. Work Item s – proposed revisions of this standard. Specific information about methods for determining the property of a astm g151 material before and after exposure are found in standards describing the method used to measure each property. In some cases, the results for the test material are compared to those for the reference material. Results obtained from y151 laboratory accelerated exposures can be considered astm g151 representative of astn use exposures only when the degree of rank correlation has been established for the astm g151 materials being tested and when the type of degradation is the same.
Results can be expressed by comparing the exposure time or radiant exposure necessary to change a characteristic property to some specified level.
Information regarding the reporting of results from exposure testing of plastic materials is described in Practice D Related Suppliers Searching for related suppliers Absence of biological agents or pollutants. Test conditions where specimens are exposed continuously to light when actual use conditions provide alternate periods of light and dark. When conducting exposures in devices astm g151 use laboratory light astm g151, it is important to consider how well the accelerated test conditions aastm reproduce property changes and failure modes associated with end-use environments for astm g151 materials being tested.
Therefore, even if results from a specific exposure test conducted according to this practice are found astm g151 be useful for comparing the relative durability of materials exposed astm g151 a particular exterior environment, it cannot be assumed astm g151 they will be useful for determining relative durability of the same materials for a different environment. 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.
Detailed information regarding procedures to be used for specific devices are found in standards describing the particular device being used. Even though it is very tempting, calculation of an acceleration factor relating astm g151 h or megajoules of radiant exposure in a laboratory accelerated test to y months or years of exterior exposure is not recommended.
ASTM G – UV EXPOSURE (GENERAL)
In addition, it is astm g151 to consider the effects of variability in both the accelerated test and outdoor exposures when setting up exposure experiments and when interpreting the results from accelerated exposure tests.
Acceleration factors are material dependent astm g151 can be significantly different for each material and for different formulations of the same material. Note 1—Carbon-arc, xenon arc, and fluorescent UV exposures were also described in Practices, and which referred to very specific equipment designs.
Reference materials, for example, blue wool test fabric, also may be used astm g151 the purpose of timing exposures. No laboratory exposure test can be specified as a total simulation of actual use conditions in outdoor environments. Work Item astm g151 – proposed revisions of this standard. An example of a statistical analysis using multiple laboratory and exterior exposures to calculate an acceleration astm g151 is described by J.
Guide G provides information for application of statistics to exposure test results Note 3-This standard is technically equivalent to ISOPart 1. The relative durability of materials in actual use conditions can be very different in different locations because of differences in UV radiation, time of wetness, relative humidity, temperature, pollutants, and astm g151 factors.
Specific information astm g151 methods for determining the property of atsm nonmetallic material before and after exposure are found in sstm describing the sstm used to measure each property. In some cases, astm g151 reference material is exposed at the same time as a test material and the exposure is conducted until there is a defined change in property of the reference material. Note Carbon-arc, xenono-arc, and fluorescent UV exposures astm g151 also described in Practices G23, G26, and G53 which atm very specific equipment designs.
Acceleration factors calculated based on the ratio of irradiance between a laboratory light source and solar radiation, even when identical bandpasses are used, do not take into consideration the effects on a material of irradiance, temperature, g1551, and differences in spectral power distribution between the laboratory light astm g151 and solar radiation.