Designation: G? 12a Standard Practice for Operating Fluorescent Ultraviolet (UV) Lamp Apparatus for Exposure of Nonmetallic Materials1. ASTM CommiKee E44 intends to address these concerns by creaIng a standard on meeIng the ASTM G‐ Standard PracIce for. OperaIng Fluorescent. Engaged Expert Terry Candlish discusses ASTM G and G tests which are used to evaluate sunlight and moisture exposure. ASTM.
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The specimen temperature permissible for the accelerated test depends on the material to be tested and on the aging criterion under consideration. Send us a request Need help or have a question? These conditions are provided for reference only See Table X2.
Furthermore, tests using the same cycles and temperatures with these two lamps may exhibit differences in ranking of materials due to difference in the proportion of UV to moisture and temperature.
These cycles would be continued for extended periods of time – up to thousands of hours – simulating even longer periods of time in the real world. Further, because there is little longer wavelength energy, the glass-?
Auditing Consulting Sourcing Training. When rays of sunlight—particularly UV rays—bombard a surface, they degrade smaller pigment particles, changing the surface color and creating a chalky effect. Originally approved in These are not necessarily preferred and no recommendation is implied. Care should be taken to keep silica levels below 0.
For any individual UVB lamp, the calculated percentage in each bandpass must fall within the minimum and maximum limits of Table 3. This practice is limited to the procedures for obtaining, measuring, and controlling conditions of exposure.
A detailed description of the type s f154-12 lamp s used shall be asstm in detail in the test report. Hemispherical on 37 degree Tilted Surface. See Practice G for detailed water quality instructions.
Consequently, the use of a radiometer to monitor and control the radiant energy is recommended. Mixing different types of lamps in a? See ISO for detailed guidance. Brass, steel, or copper shall not be used in the vicinity of the test specimens. The manufacturer is responsible for determining conformance to Table 1.
Your comments will receive careful consideration at a meeting of the responsible technical committee, which you may attend. B The data in Table 1 are based on the rectangular integration of 65 spectral power distributions for? Evaluating how your products and services meet and exceed quality, safety, sustainability and performance standards. The spray shall be uniformly distributed over the samples.
ASTM G154 and G155 Explained
Remember, these accelerated weatherization tests cannot exactly reproduce outdoor conditions, as they cannot account for altitude, seasonal variations, local geographical features, and other variables. Assurance Testing Inspection Certification. If the aim of testing is to boost color fastness, UV-A bulbs are ideal.
Element provides both types g1154-12 tests at our ISO accredited testing laboratories. Such outcomes cannot be quickly obtained in outdoor settings; therefore, these weatherization tests are invaluable in timely product development. Contact the manufacturer of the? Refer to Practice G for full cautionary guidance applicable to all laboratory weathering devices. The lamps shown in this section are representative of their type.
Accelerated Weathering (QUV) ASTM G, ASTM D, ASTM D, ISO
Cracking, peeling, de-glossing, oxidation, and tensile weakening are additional outcomes of exposure; sometimes such deterioration can even occur through window glass. The lamps discussed in this Appendix differ in the total amount of UV energy emitted and their wavelength spectrum. F For the benchmark solar spectrum, the UV irradiance to nm is 9. Asm low levels of silica in spray water can cause signi?
These numbers represent the characteristic nominal wavelength in nm of peak emission for each of these lamp types. This practice is limited to the procedures for obtaining, measuring, and controlling conditions of exposure. See Practice G for further guidance. D The window glass? Ordinary glass is essentially transparent to light above about nm.
NOTE 3—Do not mix different types of lamps. Xenon Arc Testing Weatherometers used in the G and G tests approximate performance via intense exposure to the damaging elements in sunlight.
Up to 20 test samples are mounted in the QUV and subjected to a cycle of exposure to intense ultraviolet radiation followed by moisture exposure by condensation.
This short wavelength UV can produce rapid polymer degradation and often causes degradation by mechanisms that do not occur when materials are exposed to sunlight. See Appendix X1 for lamp application guidelines.
ASTM G and G Explained | Element
NOTE 10—Evaluation of color and appearance changes of exposed materials shall be made based on comparisons to unexposed specimens of the same material which have been stored in the dark. Hemispherical on 37 Tilted Surface. Control samples and multiple material samples produce the best comparative data.