1、Designation: D1494 12D1494 17 An American National StandardStandard Test Method forDiffuse Light Transmission Factor of Reinforced PlasticsPanels1This standard is issued under the fixed designation D1494; the number immediately following the designation indicates the year oforiginal adoption or, in
2、the case 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.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope*1
3、.1 This test method covers the determination of the diffuse light transmission factor of translucent reinforced plastics buildingpanels.1.2 The values stated in SI units are to be regarded as the standard. The values given in the parentheses are for information only.1.3 The text of this standard ref
4、erences notes and footnotes which provide explanatory material. These notes and footnotes(excluding those in Tables and Figures) shall not be considered as requirements of this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is t
5、he responsibilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.NOTE 1There is no know ISO equivalent to this standardNOTE 1There is no known ISO equivalent to this s
6、tandard.1.5 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barrie
7、rs to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD883 Terminology Relating to PlasticsD1600 Terminology for Abbreviated Terms Relating to PlasticsE2935 Practice for Conducting Equivalence Testing in Laboratory ApplicationsE691
8、Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method2.2 ASTM Adjuncts:Test Cabinet for Diffuse Light Transmission Factor of Reinforced Panels33. Terminology3.1 Definitions:GeneralDefinitions are in accordance with Terminology D883 and abbreviations with Termin
9、ology D1600,unless otherwise indicated.3.1 GeneralDefinitions are in accordance with Terminology D883 and abbreviations with Terminology D1600, unlessotherwise indicated.4. Significance and Use4.1 The purpose of this test method is to obtain the diffuse light transmittance factor of both flat and co
10、rrugated translucentbuilding panels by the use of simple apparatus and by employing as a light source a combination of fluorescent tubes whose energydistribution closely approximates CIE Source C.1 This test method is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct respons
11、ibility of Subcommittee D20.24 on Plastic Building Products.Current edition approved Oct. 1, 2012Dec. 1, 2017. Published November 2012January 2018. Originally approved in 1957. Last previous edition approved in 20082012as D1494 97 (2008)D1494 12.1. DOI: 10.1520/D1494-12.10.1520/D1494-17.2 For refere
12、ncedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Detailed working drawings and a bill of materials for this equipment ca
13、n be obtained at a nominal charge from ASTM Headquarters, 100 Barr Harbor Drive, PO BoxC700, West Conshohocken, PA 194282959. Order Adjunct: ADJD1494.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
14、 previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary o
15、f Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15. Apparatus5.1 The apparatus for this test method shall consist of a transmissometer, Fig. 1, comprising essentially the following:5
16、.1.1 Light SourceThe illumination shall consist of twelve 20-W fluorescent tubes which are assembled in three banks of fourtubes each, according to the following schedule: daylight, deluxe cool white, blue, and daylight.5.1.2 PhotometerThe photometer shall consist of a photocell and of a galvanomete
17、r. The photocell shall be of the barrier-layertype and shall contain a visual correction filter. The assembly preferably should be hermetically sealed into plastic as a protectionagainst moisture. The indicating galvanometer should contain one scale graduated from 0 to 100, and a circuit with suffic
18、ientvariable resistance so that the sensitivity of the photometer can be adjusted over the range of 50 to 100 footcandles.5.1.3 Test Cabinet, constructed in accordance with the following dimensions.35.1.3.1 The transmitted area of the test specimen shall be 610.0 6 1.6 mm by 610.0 6 1.6 mm (24 6 116
19、 in. by 24 6 116 in.).5.1.3.2 The distance from the bottom of the fluorescent tubes to the bottom of the test specimen shall be 203.0 6 0.8 mm (86 132 in.).5.1.3.3 A 4.8-mm (316-in.) thick, white, standard outdoor, translucent diffusing plate shall be placed between the light sourceand the test spec
20、imen so that the distance from the bottom of the diffusing plate to the bottom of the test specimen is 31.8 6 0.8mm (114 6 132 in.).5.1.3.4 The photocell shall be positioned below the center axis of the test specimen so that the distance from the bottom of thespecimen to the top of the cell is 283.0
21、 6 0.8 mm (1118 6 132 in.).5.1.3.5 A masking plate containing a 31.8-mm (114-in.) diameter hole in its center shall be placed between the test specimenand the photocell so that the distance from the bottom of the test specimen to the bottom of the masking plate shall be 233.0 60.8 mm (934 6 132 in.)
22、.Metric Equivalentsin. mm in. mm in. mm in. mm132 0.8 34 19.1 834 222 2434 634316 4.8 114 31.8 934 248 2512 648737 5.6 112 38.1 12 305 28 71114 6.4 2 50.8 14 356 2912 749932 7.1 634 172 24 610 3812 97838 9.5FIG. 1 Assembly Drawing of TransmissometerD1494 1726. Standardization of Transmissometer6.1 C
23、enter the photocell beneath the 31.8-mm (114-in.) diameter hole in the bottom masking plate. Place the galvanometer ina flat level position. Ensure that no current flows in the electrical circuit by opening the circuit.Adjust the position of the indicatingneedle on the galvanometer to read “0 by mea
24、ns of the zero adjustment knob. Close the galvanometer circuit. Turn on theillumination in the transmissometer. Wait a minimum of 20 min to permit the transmissometer to reach equilibrium conditions.Adjust the galvanometer to read “100.“100.” The instrument is now ready to be used for measurements o
25、f diffuse lighttransmission factor.7. Test Specimens7.1 The test specimens shall consist of translucent reinforced plastic panels having a minimum length of 610 mm (24 in.) anda width greater than 610 mm (24 in.), but not exceeding 711 mm (28 in.).8. Conditioning8.1 ConditioningCondition the test sp
26、ecimens at 23 6 2C (73 6 4F) and 50 6 10 % relative humidity for not less than 40h prior to test in accordance with Procedure A of Practice D618, for those test methods where conditioning is required. In casesof disagreement, the tolerances shall be 61C (62F) and 62 %65 % relative humidity.8.2 Test
27、ConditionsConduct tests in the Standard LaboratoryAtmosphere of 2362C (7364C)4F) and 50610 % relativehumidity, unless otherwise specified in the test methods or in this specification. In cases of disagreement, the tolerances shall be61C (62F) and 62 %65 % relative humidity.9. Procedure9.1 In making
28、a measurement, place the test specimen in the test cabinet so that it completely covers the 610 by 610-mm (24by 24-in.) space. The transmittance is read on the galvanometer in percent.10. Report10.1 The report shall include the following:10.1.1 The source and identity of test specimens.10.1.2 The pe
29、rcent transmission of the test specimen.10.1.3 The average thickness of the test specimen in inches expressed to the nearest 0.025 mm (0.001 in.) and comprising atleast ten individual measurements.11. Precision and Bias411.1 Table 1 is based on a round robin conducted in 1987 in accordance with Prac
30、tice E691, involving five materials tested byseven laboratories. Because of the nonuniform nature of large corrugated sheets, the five samples were sequentially sent to theseven participating laboratories. Each test result is an individual determination. Each laboratory obtained three test results f
31、or eachmaterial.NOTE 2The explanation of Ir and IR (11.2 through 11.2.3) are only intended to present a meaningful way of considering the approximate precisionof this test method. The data in Table 1 should not be vigorously applied to acceptance or rejection of materials as these data specific to t
32、he round robinand may not be representative of other lots, conditions, materials, or laboratories.11.1.1 Users of this test method should apply the principles outlined in Practice E691 to generate data specific to their laboratoryand materials or between specific laboratories. The principles of 11.2
33、 through 11.2.3 then would be valid for such data.11.2 Concept of Ir and IRIf Sr and SR have been calculated from a large enough body of data, and for test results that arethe individual result from testing one specimen:4 Supporting data are available from ASTM Headquarters. Request RR:D20-1145RR: .
34、D20 1145.TABLE 1 Precision Values in the Units of PercentMaterial Average SrA SRB IrC IRDSample #4 6.1 0.36 1.08 1.02 3.06Sample #5 24.1 0.59 2.48 1.67 7.02Sample #1 59.7 0.45 5.01 1.27 14.18Sample #3 73.0 0.76 3.19 2.16 9.03Sample #2 95.6 0.64 1.61 1.81 4.56ASr is the within-laboratory standard dev
35、iation of the average.BSR is the between-laboratory standard deviation of the average.CIr = 2.83 Sr; andDIR = 2.83 SR.D1494 17311.2.1 Ir: Repeatability (comparing two test results for the same material, obtained by the same operator using the sameequipment on the same day)the two test results should
36、 be judged not equivalent if they differ by more than the The value belowwhich the absolute difference between two individual test results obtained under repeatability conditions is likely to be expectedto occur with a probability of approximately 0.95 (95 %). Ir value for that material.11.2.2 IR: R
37、eproducibility (Comparing two test results for the same material, obtained by different operators using differentequipment on different days)the two test results should be judged not equivalent if they differ by more than the The value belowwhich the absolute difference between two individual test r
38、esults obtained under reproducibility conditions is likely to be expectedto occur with a probability of approximately 0.95 (95 %).IR value for that material.11.2.3 Any judgment perEquivalence testing on 11.2.1 andnumerical data 11.2.2 would have an approximate 95 % (0.95)probability from two sources
39、 shall be conducted in accordance with Practice E2935of being correct. or any known method forjudging the equivalence of two means.NOTE 3Example, a t-test.11.3 Bias is systematic error which contributes to the difference between a test result and a true (or reference) value. There areno recognized s
40、tandards on which to base an estimate of bias for this test method.12. Keywords12.1 building panels; diffuse light transmission factor; reinforced plasticsSUMMARY OF CHANGESCommittee D20 has identified the location of the following changes to this standard since the last issue(D1494-97(2008)D14941 )
41、 -12) that may impact the use of this standard. (December 1, 2017)(1) Removed D4968 reference in Section Revised 2.1, added reference to E2935.2.(2) Removed C618 reference from SectionRevised 8.1 and 8.2, changed 2.6 2% to 5% per D618-13.(3) AddedRevised D618 reference in Section8.2, corrected C to
42、2.F.(4) Updated sectionRevised 11.2.1, 8.1 per D618-08.11.2.2, 11.2.3, new rewording.(5) Updated sectionAdded Note 8.2 per D618-08.3.Committee D20 has identified the location of the following changes to this standard since the last issue(D1494-97(2000)1 ) that may impact the use of this standard.(1)
43、 Reworded ISO equivalency statement per Guide D4968.D1494 174(2) Adjusted significant digits in 5.1.3.1, 5.1.3.2, 5.1.3.4 and 5.1.3.5.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standa
44、rd are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif
45、 not revised, either reapproved or withdrawn.Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, whic
46、h you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,Un
47、ited States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 175
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