1、Designation: G154 12 G154 12aStandard Practice forOperating Fluorescent Ultraviolet (UV) Lamp Apparatus forExposure of Nonmetallic Materials1This standard is issued under the fixed designation G154; the number immediately following the designation indicates the year oforiginal adoption or, in the ca
2、se of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This practice covers the basic principles and operating procedures for using fluorescent
3、UV light, and water apparatusintended to reproduce the weathering effects that occur when materials are exposed to sunlight (either direct or through windowglass) and moisture as rain or dew in actual usage. This practice is limited to the procedures for obtaining, measuring, andcontrolling conditio
4、ns of exposure. A number of exposure procedures are listed in an appendix; however, this practice does notspecify the exposure conditions best suited for the material to be tested.NOTE 1Practice G151 describes performance criteria for all exposure devices that use laboratory light sources. This prac
5、tice replaces Practice G53,which describes very specific designs for devices used for fluorescent UV exposures. The apparatus described in Practice G53 is covered by this practice.1.2 Test specimens are exposed to fluorescent UV light under controlled environmental conditions. Different types of flu
6、orescentUV light sources are described.1.3 Specimen preparation and evaluation of the results are covered in ASTM 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 changein propertie
7、s 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 responsibilityof the user of this standard t
8、o establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.1.6 This standard is technically similar to ISO 4892-3 and ISO DIS 11507.2. Referenced Documents2.1 ASTM Standards:2D3980 Practice for Interlaboratory Testing of Paint and Relate
9、d Materials (Withdrawn 1998)3E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test MethodG53 Practice for Operating Light-and Water-Exposure Apparatus (Fluorescent UV-Condensation Type) for Exposure ofNonmetallic Materials (Withdrawn 2000)3G113 Terminology Relati
10、ng to Natural and Artificial Weathering Tests of Nonmetallic MaterialsG151 Practice for Exposing Nonmetallic Materials in Accelerated Test Devices that Use Laboratory Light Sources2.2 CIE Standard:CIE-Publ. No. 85: Recommendations for the Integrated Irradiance and the Spectral Distribution of Simula
11、ted Solar Radiationfor Testing Purposes42.3 ISO Standards:ISO 4582 PlasticsDetermination of the Changes of Colour and Variations in Properties After Exposure to Daylight UnderGlass, Natural Weathering or Artificial Light51 This practice is under the jurisdiction of ASTM Committee G03 on Weathering a
12、nd Durabilityand is the direct responsibility of Subcommittee G03.03 on Simulated andControlled Exposure Tests.Current edition approved Dec. 1, 2012Dec. 15, 2012. Published December 2012. Originally approved in 1997. Last previous edition approved in 2006 as G154 06. DOI:10.1520/G0154-12.10.1520/G01
13、54-12a.2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historical stan
14、dard is referenced on www.astm.org.4 Available from Secretary, U.S. National Committee, CIE, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899.5 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.
15、This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior edi
16、tions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-295
17、9. United States1ISO 4892-1 PlasticsMethods of Exposure to Laboratory Light Sources, Part 1, Guidance5ISO 4892-3 PlasticsMethods of Exposure to Laboratory Light Sources, Part 3, Fluorescent UV lamps5ISO DIS 11507 Paint and VarnishesExposure of Coatings to Artificial Weathering in ApparatusExposure t
18、o FluorescentUltraviolet and Condensation Apparatus53. Terminology3.1 DefinitionsThe definitions given in Terminology G113 are applicable to this practice.3.2 Definitions of Terms Specific to This StandardAs used in this practice, the term sunlight is identical to the terms daylightand solar irradia
19、nce, global as they are defined in Terminology G113.3.2.1 Fluorescent Ultraviolet (UV) ApparatusAn apparatus for performing exposure tests using fluorescent UV lamps as thelight source.4. Summary of Practice4.1 Specimens are exposed to repetitive cycles of light and moisture under controlled environ
20、mental conditions.4.1.1 Moisture is usually produced by condensation of water vapor onto the test specimen or by spraying the specimens withdemineralized/deionized water.4.2 The exposure condition may be varied by selection of:4.2.1 The fluorescent lamp,4.2.2 The lamps irradiance level,4.2.3 The typ
21、e of moisture exposure,4.2.4 The timing of the light and moisture exposure,4.2.5 The temperature of light exposure, and4.2.6 The temperature of moisture exposure, and4.2.7 The timing of a light/dark cycle.4.3 Comparison of results obtained from specimens exposed in same model of apparatus should not
22、 be made unlessreproducibility has been established among devices for the material to be tested.4.4 Comparison of results obtained from specimens exposed in different models of apparatus should not be made unlesscorrelation has been established among devices for the material to be tested.5. Signific
23、ance and Use5.1 The use of this apparatus is intended to induce property changes associated with the end use conditions, including the effectsof the UV portion of sunlight, moisture, and heat. These exposures may include a means to introduce moisture to the test specimen.Exposures are not intended t
24、o 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 condensi
25、ng humidity.NOTE 2Caution: 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 fr
26、om the use of this practice unless accompanied by a report detailing the specificoperating conditions in conformance with the Section 10.5.2.1 It is recommended that a similar material of known performance (a control) be exposed simultaneously with the testspecimen to provide a standard for comparat
27、ive purposes. It is recommended that at least three replicates of each material evaluatedbe exposed in each test to allow for statistical evaluation of results.6. Apparatus6.1 Laboratory Light SourceThe light source shall be fluorescent UV lamps. A variety of fluorescent UV lamps can be usedfor this
28、 procedure. Differences in lamp intensity or spectrum may cause significant differences in test results. A detailed descriptionof the type(s) of lamp(s) used should be stated in detail in the test report. The particular testing application determines which lampshould be used. See Appendix X1 for lam
29、p application guidelines.NOTE 3Do not mix different types of lamps. Mixing different types of lamps in a fluorescent UV light apparatus may produce major inconsistenciesin the light falling on the samples, unless the apparatus has been specifically designed to ensure a uniform spectral distribution.
30、NOTE 4Many fluorescent lamps age significantly with extended use. Follow the apparatus manufacturers instructions on the procedure necessaryto maintain desired irradiance (1,2).6.1.1 Actual irradiance levels at the test specimen surface may vary due to the type or manufacturer of the lamp used, or b
31、oth,the age of the lamps, the distance to the lamp array, and the air temperature within the chamber and the ambient laboratorytemperature. Consequently, the use of a radiometer to monitor and control the radiant energy is recommended.6.1.2 Several factors can affect the spectral power distribution
32、of fluorescent UV lamps:G154 12a26.1.2.1 Aging of the glass used in some types of lamps can result in changes in transmission. Aging of glass can result in asignificant reduction in the short wavelength UV emission of some lamp types,6.1.2.2 Accumulation of dirt or other residue on lamps can affect
33、irradiance,6.1.2.3 Thickness of glass used for lamp tube can have large effects on the amount of short wavelength UV radiationtransmitted, and6.1.2.4 Uniformity and durability of phosphor coating.6.1.3 Spectral Irradiance:NOTE 5Fluorescent UVA lamps are available with a choice of spectral power dist
34、ributions that vary significantly. The more common may be identifiedas UVA-340 and UVA-351. These numbers represent the characteristic nominal wavelength (in nm) of peak emission for each of these lamp types. Theactual peak emissions are at 343 and 350 nm, respectively.6.1.3.1 Spectral Irradiance of
35、 UVA-340 Lamps for Daylight UVThe spectral power distribution of UVA-340 fluorescent lampsshall comply with the requirements specified in Table 1.NOTE 6The main application for UVA-340 lamps is for simulation of the short and middle UV wavelength region of daylight.6.1.3.2 Spectral Irradiance of UVA
36、-351 Lamps for Daylight UV Behind Window GlassThe spectral power distribution ofUVA-351 lamp for Daylight UV behind Window Glass shall comply with the requirements specified in Table 2.NOTE 7The main application for UVA-351 lamps is for simulation of the short and middle UV wavelength region of dayl
37、ight which has been filteredthrough window glass (3).6.1.3.3 Spectral Irradiance of UVB-313 LampsThe spectral power distribution of UVB-313 fluorescent lamps shall complywith the requirements specified in Table 3.NOTE 8Fluorescent UVB lamps have the spectral distribution of radiation peaking near th
38、e 313-nm mercury line. They emit significant amounts ofradiation below 300 nm, the nominal cut on wavelength of global solar radiation, that may result in aging processes not occurring outdoors. Use of thislamp is not recommended for sunlight simulation. See Table 3.TABLE 1 Relative Ultraviolet Spec
39、tral Power DistributionSpecification for Fluorescent UVA-340 Lamps for Daylight UVA,BSpectralBandpassWavelength innmMinimumPercentCBenchmark SolarRadiationPercentD,E,FMaximumPercentC 290 0.01290 # # 320 5.9 5.8 9.3320 # 360 60.9 40.0 65.5360 # 400 26.5 54.2 32.8A Data in Table 1 are the irradiance i
40、n the given bandpass expressed as apercentage of the total irradiance from 290 to 400 nm. The manufacturer isresponsible for determining conformance to Table 1. Annex A1 states how todetermine relative spectral irradiance.B The data in Table 1 are based on the rectangular integration of 65 spectral
41、powerdistributions for fluorescent UV devices operating with UVA 340 lamps of variouslots and ages. The spectral power distribution data is for lamps within the agingrecommendations of the device manufacturer. The minimum and maximum dataare at least the three sigma limits from the mean for all meas
42、urements.C The minimum and maximum columns will not necessarily sum to 100 % becausethey represent the minimum and maximum for the data used. For any individualspectral power distribution, the calculated percentage for the bandpasses in Table1 will sum to 100 %. For any individual fluorescent UVA-34
43、0 lamp, the calculatedpercentage in each bandpass must fall within the minimum and maximum limits ofTable 1. Test results can be expected to differ between exposures using deviceswith fluorescent UVA-340 lamps in which the spectral power distributions differ byas much as that allowed by the toleranc
44、es. Contact the manufacturer of thefluorescent UV devices for specific spectral power distribution data for thefluorescent UVA-340 lamp used.D The benchmark solar radiation data is defined in ASTM G177 and is foratmospheric conditions and altitude chosen to maximize the fraction of shortwavelength s
45、olar UV. While this data is provided for comparison purposes only, itis desirable for the laboratory accelerated light source to provide a spectrum thatis a close match to the benchmark solar spectrum.E Previous versions of this standard used solar radiation data from Table 4 of CIEPublication Numbe
46、r 85. See Appendix X3 for more information comparing thesolar radiation data used in this standard with that for CIE 85 Table 4.F For the benchmark daylight spectrum, the UV irradiance (290 to 400 nm) is 9.8 %and the visible irradiance (400 to 800 nm) is 90.2 % expressed as a percentage ofthe total
47、irradiance from 290 to 800 nm. Because the primary emission offluorescent UV lamps is concentrated in the 300 to 400 nm bandpass, there arelimited data available for visible light emissions of fluorescent UV lamps.G154 12a36.2 Test ChamberThe design of the test chamber may vary, but it should be con
48、structed from corrosion resistant material and,in addition to the radiant source, may provide for means of controlling temperature and relative humidity. When required, provisionshall be made for the spraying of water on the test specimen for the formation of condensate on the exposed face of the sp
49、ecimenor for the immersion of the test specimen in water.6.2.1 The radiant source(s) shall be located with respect to the specimens such that the uniformity of irradiance at the specimenface complies with the requirements in Practice G151.6.2.2 Lamp replacement, lamp rotation, and specimen repositioning may be required to obtain uniform exposure of allspecimens to UV radiation and temperature. Follow manufacturers recommendation for lamp replacement and rotation.6.3 Instrument CalibrationTo ensure standardization and accuracy, the instruments a
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