1、Designation: D 4459 06Standard Practice forXenon-Arc Exposure of Plastics Intended for IndoorApplications1This standard is issued under the fixed designation D 4459; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This practice covers specific procedures and test condi-tions that are applicable for exposure of plastics in windowglass
3、-filtered xenon-arc devices in accordance with PracticesG 151 and G 155 for evaluating the stability of plasticsintended for use in indoor applications.1.2 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of thi
4、s standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.NOTE 1There is no known ISO equivalent to this practice.2. Referenced Documents2.1 ASTM Standards:2D 1729 Practice for Visual Appraisal of Colors and ColorDifferen
5、ces of Diffusely-Illuminated Opaque MaterialsD 2244 Practice for Calculation of Color Tolerances andColor Differences from Instrumentally Measured ColorCoordinatesD 3980 Practice for Interlaboratoy Testing of Paint andRelated MaterialsD 4674 Practice for Accelerated Testing for Color Stabilityof Pla
6、stics Exposed to Indoor Office EnvironmentsD 5870 Practice for Calculating Property Retention Indexof PlasticsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodG113 Terminology Relating to Natural and ArtificialWeathering Tests of Nonmetallic MaterialsG
7、 141 Guide forAddressing Variability in Exposure Testingof Nonmetallic MaterialsG 147 Practice for Conditioning and Handling of Nonme-tallic Materials for Natural and Artificial Weathering TestsG 151 Practice for Exposing Nonmetallic Materials in Ac-celerated Test Devices that Use Laboratory Light S
8、ourcesG 155 Practice for Operating Xenon Arc Light Apparatusfor Exposure of Non-Metallic MaterialsG 169 Guide forApplication of Basic Statistical Methods toWeathering Tests3. Terminology3.1 The definitions in Terminology G113are applicable tothis practice.4. Significance and Use4.1 This practice is
9、intended to simulate the effects pro-duced by exposure to solar radiation through glass. Thispractice uses exposure in a xenon-arc device equipped withwindow glass filters and operated in accordance with PracticesG 151 and G 155.NOTE 2Practice D 4674 describes exposures in a device that uses acombin
10、ation of fluorescent “cool white” and ultraviolet (UV) lamps tosimulate the effects of exposures to indoor fluorescent light and windowglass filtered daylight.4.2 WarningVariation in results may be expected whenoperating conditions are varied within the accepted limits ofthis practice. Therefore, al
11、l references to the use of this practicemust be accompanied by a report prepared in accordance withSection 9 that describes the specific operating conditions used.Refer to Practice G 151 for detailed information on the caveatsapplicable to use of results obtained in accordance with thispractice.NOTE
12、 3Additional information on sources of variability and onstrategies for addressing variability in the design, execution and dataanalysis of laboratory accelerated exposure tests is found in Guide G 141.4.3 Test results will depend upon the care that is taken tooperate the equipment in accordance wit
13、h Practice G 155.Significant factors include regulation of line voltage, tempera-ture and humidity control, and condition and age of the burnerand filters.1This practice is under the jurisdiction ofASTM Committee D20 on Plastics andis the direct responsibility of Subcommittee D20.50 on Durability of
14、 Plastics.Current edition approved Sept. 1, 2006. Published October 2006. Originallyapproved in 1985. Last previous edition approved in 1999 as D 4459 - 99.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of AST
15、MStandards volume information, refer to the standards Document Summary page onthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.4 Reproducibility of t
16、est results between laboratories hasbeen shown to be good when the stability of materials isevaluated in terms of performance ranking compared to othermaterials or to a control.3,4Therefore, exposure of a similarmaterial of known performance (a control) at the same time asthe test materials is stron
17、gly recommended. It is recommendedthat at least three replicates of each material be exposed toallow for statistical evaluation of results.5. Apparatus5.1 Use xenon-arc apparatus that conforms to the require-ments defined in Practices G 151 and G 155.5.2 The spectral power distribution of the xenon-
18、arc lampshall conform to the requirements described in Practice G 155for a xenon-arc lamp with window glass filters.5.3 Unless otherwise specified, use a xenon-arc deviceequipped with a radiometer capable of monitoring eithernarrow-band or broad-band irradiance incident on test speci-mens.6. Test Sp
19、ecimen6.1 The size and shape of specimens to be exposed will bedetermined by the specifications of the particular test methodused to evaluate the effects of the exposure on the specimens;the test method shall be determined by the parties concerned.Where practical, it is recommended that specimens be
20、 sized tofit specimen holders and racks supplied with the exposureapparatus. Unless supplied with a specific backing as anintegral part of the test, specimens shall be mounted so thatonly the minimum specimen area required for support by theholder shall be covered. This unexposed surface must not be
21、used as part of the test area.6.2 Unless otherwise specified, expose at least three repli-cate specimens of each test material and of the control material,if used.6.3 Follow the procedures described in Practice G 147 foridentification and conditioning and handling of specimens oftest, control, and r
22、eference materials prior to, during, and afterexposure.6.4 Do not mask the face of specimen for the purpose ofshowing on one panel the effects of various exposure times.Misleading results may be obtained by this method, since themasked portion of the specimen is still exposed to temperatureand humid
23、ity cycles that in many cases will affect results.6.5 Since the thickness of a specimen may affect markedlythe results, thickness of test and control specimens shall bewithin 610 % of the nominal dimensions.NOTE 4This is especially important if changes in mechanical prop-erties are being investigate
24、d.6.6 Incident energy at the extremes of the specimen expo-sure area in older equipment may be only 70 % of that at thecenter. If the irradiance at any position within the exposure areais less than 90 % of the peak irradiance, follow one of theprocedures outlined in Practice G 155 to ensure either e
25、qualradiant exposure or compensation for differences in radiantexposure.6.7 Retain a supply of unexposed file specimens of allmaterials evaluated.6.7.1 When destructive tests are run, ensure than sufficientfile specimens are retained so that the property of interest canbe determined on unexposed fil
26、e specimens each time exposedmaterials are evaluated.6.8 Specimens should not be removed from the exposureapparatus for more than 24 h and then returned for additionaltests, since this does not produce the same results on allmaterials as tests run without this type of interruption. Whenspecimens are
27、 removed from the exposure apparatus for 24 h ormore then returned for additional exposure, report the elapsedtime as noted in accordance with Section 9.NOTE 5Since the stability of the file specimens is also time-dependent, users are cautioned that over prolonged exposure periods, orwhere small dif
28、ferences in the order of acceptable limits are anticipated,comparison of exposed specimens with the file specimen may not be valid.Instrumental measurements are recommended whenever possible.7. Procedure7.1 Operate the xenon-arc device in continuous light modewithout any water spray.7.2 Unless other
29、wise specified, control the irradiance at oneof the following levels:7.2.1 0.3 6 0.02 W/(m2 nm) at 340 nm.7.2.2 0.8 6 0.05 W/(m2 nm) at 420 nm.7.2.3 36.5 6 2.5 W/m2between 300 and 400 nm.7.2.4 If the exposure device is not equipped with irradiancecontrol, follow the manufacturers recommendations to
30、pro-duce the specified irradiance levels.7.3 Unless otherwise specified, control the temperature ofan uninsulated black panel at 55 6 2C 131 6 4F.7.4 Unless otherwise specified, control relative humidity at55 6 5%.7.5 It is recommended that a control material be exposed atthe same time as the test s
31、pecimens for comparison purposes,if performance comparisons are not being made between thetest materials themselves. All concerned parties must agree onthe control material used.7.6 Unless otherwise specified, expose at least three repli-cates of each test and control material evaluated to allow for
32、statistical evaluation of results.7.6.1 It is recommended that all unused spaces in thespecimen exposure area be filled with non-ultraviolet reflectingblanks, for example, grey card stock.7.7 Expose the test and control materials (if used) for a timeor radiant exposure agreed upon between all intere
33、sted parties.7.7.1 Determine the color difference between the exposedand file specimens in accordance with Test Method D 2244 orPractice D 1729. If materials are not evaluated within 4 h afterremoval from exposure, store specimens at a temperature of-15 to -20C. Test all specimens within one week af
34、ter removalfrom exposure.3Fischer, R., “Results of Round Robin Studies of Light- and Water-ExposureStandard Practices,” Accelerated and Outdoor Durability Testing of OrganicMaterials, ASTM STP 1202, Warren D. Ketola and Douglas Grossman, eds.,American Society for Testing and Materials, Philadelphia,
35、 1993.4Ketola, W., and Fischer, R., “Characterization and Use of Reference Materialsin Accelerated Durability Tests,” VAMAS Technical Report No. 30, available fromNIST, Gaithersburg, MD.D44590627.7.2 Where desired, measurement of other properties canalso be made on exposed specimens.7.8 When a contr
36、ol material is used, a complete descriptionof the control material shall be included when reporting resultsobtained in accordance with this practice.8. Periods of Exposure and Evaluation of Test Results8.1 In most cases, periodic evaluation of test and controlmaterials is necessary to determine the
37、variation in magnitudeand direction of property change as a function of exposure timeor radiant exposure.8.2 The time or radiant exposure necessary to produce adefined change in a material property can be used to evaluateor rank the stability of materials. This method is preferred overevaluating mat
38、erials after an arbitrary exposure time or radiantexposure.8.2.1 Exposure to an arbitrary time or radiant exposure maybe used for the purpose of a specific test if agreed uponbetween the parties concerned or if required for conformanceto a particular specification. When a single exposure period isus
39、ed, select a time or radiant exposure that will produce thelargest performance differences between the test materials orbetween the test material and the control material.8.2.2 The minimum exposure time used shall be that nec-essary to produce a substantial change in the property ofinterest for the
40、least stable material being evaluated. Anexposure time than produces a significant change in one type ofmaterial cannot be assumed to be applicable to other types ofmaterials.8.2.3 The relation between time in failure in an exposureconducted in accordance with this practice and service life inan out
41、door environment requires determination of a validacceleration factor. Do not use arbitrary acceleration factorsrelating time in an exposure conducted in accordance with thispractice and time in an outdoor environment because they cangive erroneous information. The acceleration factor is material-de
42、pendent and is only valid if it is based on data from asufficient number of separate exterior and laboratory-accelerated exposures so that results used to relate times tofailure in each exposure can be analyzed using statisticalmethods.NOTE 6An example of a statistical analysis using multiple-labora
43、toryand exterior exposures to calculate an acceleration factor is described bySimms.5See Practice G 151 for more information and additional cautionsabout the use of acceleration factors.8.3 After each exposure increment, evaluate or rate changesin exposed test specimens in accordance with applicable
44、ASTM test methods.NOTE 7For some materials, changes may continue after the specimenhas been removed from the exposure apparatus. Measurements (visual orinstrumental) should be made within a standardized time period or asagreed upon between interested parties. The standardized time periodneeds to con
45、sider conditioning prior to testing.8.4 Use of results from exposures conducted in accordancewith this practice in specifications:8.4.1 If a standard or specification for general use requires adefinite property level after a specific time or radiant exposurein an exposure test conducted in accordanc
46、e with this practice,base the specified property level on results from round-robinexperiments run to determine the test reproducibility from theexposure and property measurement procedures. Conduct theseround robins in accordance with Practice E 691 or PracticeD 3980 and include a statistically repr
47、esentative sample of alllaboratories or organizations who would normally conduct theexposure and property measurement.8.4.2 If a standard or specification for use between two orthree parties requires a definite property level after a specifictime or radiant exposure in an exposure test conducted ina
48、ccordance with this practice, base the specified property levelon two independent experiments run in each laboratory todetermine the reproducibility for the exposure and propertymeasurement process. The reproducibility of the exposure/property measurement process is then used to determine theminimum
49、 level of property after the exposure that is mutuallyagreeable to all parties.8.4.3 When reproducibility in results from an exposure testconducted in accordance with this practice has not beenestablished through round-robin testing, specify performancerequirements for materials in terms of comparison (ranked) toa control material. All specimens shall be exposed simulta-neously in the same device. All concerned parties must agreeon the specific control material used.8.4.3.1 Conduct analysis of variance to determine whetherany differences between test materials and contro
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