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.
|Country:||Saint Kitts and Nevis|
|Published (Last):||3 September 2006|
|PDF File Size:||5.32 Mb|
|ePub File Size:||6.15 Mb|
|Price:||Free* [*Free Regsitration Required]|
Cycle 2 has been widely used for coatings.
ASTM Ga 非金属材料的萤光UV灯曝晒_百度文库
Control samples and multiple material samples produce the best comparative data. It is impossible to recreate nature in the lab. When comparing relative spectral power distribution data to the spectral power distribution requirements of this standard, use the rectangular integration technique. Thermometers shall conform to the descriptions found in Practice G It is recommended that at least three replicates of each material evaluated be exposed in each test to allow for statistical evaluation of results.
The lamps shown in this section are representative of their type. Whether your business is local or global, we can ensure your products meet quality, health, environmental, safety, and social accountability standards for virtually any market around the world.
Therefore, no reference shall be made to results from the use of this practice unless accompanied by a report detailing the speci?
Parts may be accommodated depending on size.
If the aim of testing is to boost color fastness, UV-A bulbs are ideal. Cycle 7 has been used for thermal shock and for erosion testing of gg154-12 for wood. However, performance comparisons under the controlled conditions of accelerated weathering can be compared to documented performance of materials and coatings that have experienced extended periods of end use exposure.
ASTM G154 and G155 Explained
The standard sample g15-412 can hold one sample 3 x 12 inches 75 x mm or two samples qstm x 6 inches 75 x mm.
Include a control, to act as a weatherization standard. Use of this lamp is not recommended for sunlight simulation. When reproducibility in results from an exposure test conducted according to this practice have not been established through round-robin testing, performance requirements for materials shall be speci? Send us a request Need help or have a question?
B The data in Table 1 are based on the rectangular integration of 65 spectral power distributions for? Apparatus operated in ambient temperatures above or below this range may produce irradiances different from devices operated in the recommended manner. These numbers represent the characteristic nominal wavelength in nm of peak emission for each of these lamp types. Element can provide you with critically important data on your product or part’s performance in response to typical or extreme environmental stresses and conditions.
The apparatus described in Practice G53 is covered by this practice. The shorter, more damaging UVB wavelengths are the most greatly affected. The total irradiance in each wavelength bandpass is then summed and divided by the speci? Without testing in a specific location over a number of years, it is impossible to perfectly predict product response. As shown in Fig. These conditions are provided for reference only. Due to time constraints, however, many producers employ the G and G laboratory chamber tests for reliable exposure results in shorter time periods.
Element has been helping companies make Certain for over years.
Recreate specialized conditions with filters. The default lamp for this and other cycles is the UVB lamps with peak emission at nm, but? NOTE 1—Practice G describes performance criteria for all exposure devices that use laboratory light sources. The design of the experiment used to determine the speci?
The manufacturer is responsible for determining conformance to Table 1. 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.
In the ASTM G test, xenon arc lamps simulate full-spectrum sunlight within a controlled test chamber. These exposures may include a means to introduce moisture to the test specimen. 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. For any individual UVB lamp, the calculated percentage in each bandpass must fall within the minimum and maximum limits of Table 3.
Whenever possible, calibration should be traceable to national or international standards. 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. Interruptions to service the apparatus and to inspect specimens shall be minimized.
NOTE 3—Do not mix different types of lamps. D The benchmark solar radiation data is de? Xenon Arc Testing Weatherometers used in the G and G tests approximate performance via intense exposure to the damaging elements in sunlight.
The minimum and maximum data are at least the three sigma limits from the mean for all measurements. B The data in Table 2 are based on the rectangular integration of 21 spectral power distributions for?