1、Designation: C 1258 08Standard Test Method forElevated Temperature and Humidity Resistance of VaporRetarders for Insulation1This standard is issued under the fixed designation C 1258; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、 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. Scope1.1 This test method covers the determination of the agingresistance of flexible low permeance vapor retarder
3、s forthermal insulation as classified in Specification C 1136. Watervapor permeance measurement and visual inspection afterexposure at elevated temperature and humidity are used toassess vapor retarder response.1.2 Typical vapor retarders applicable to this test methodthat are intended for indoor us
4、e include foil-scrim-kraft lami-nates, metallized polyester-scrim-kraft laminates, treated fab-rics, treated papers, films, foils, or combinations of thesematerials that may comprise a vapor retarder material. This testmethod is not intended for assessment of the liquid-appliedcoatings, sealants, or
5、 mastics commonly used with insulationproducts.1.3 The values stated in inch-pound units are to be regardedas standard. The SI units given in parentheses are for informa-tion purposes only.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is
6、 theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C 168 Terminology Relating to Thermal InsulationC 1136 Specification for Flexible,
7、Low Permeance VaporRetarders for Thermal InsulationE 96/E 96M Test Methods for Water Vapor Transmission ofMaterials3. Terminology3.1 Terminology C 168 shall be considered as applying tothe terms used in this specification.4. Summary of Test Method4.1 The vapor retarders are subjected to accelerated
8、agingvia elevated temperature and humidity at 120F (49C) and95 % relative humidity for a period of 28 days, then visuallyinspected for corrosion (if applicable), delamination, or otherdegradation. Water vapor permeance in accordance with TestMethods E 96/E 96M is measured after humid aging.5. Signif
9、icance and Use5.1 On sub-ambient temperature systems, humid ambientconditions cause a vapor driving force toward the insulationwhich, if not retarded, is detrimental to the insulations thermalresistance. Therefore a vapor retarder should resist degrada-tion. Degradation in this test method is induce
10、d by elevatedtemperature and humidity conditions.6. Apparatus6.1 Environmental Chamber, capable of maintaining 120 62F (49 6 1C) and 95 6 2 % relative humidity, using distilledor deionized water as the humidity source. The chamber shallbe of the air-circulating variety.6.2 Lighted Box in a Darkened
11、RoomA lighted box is anenclosure having five opaque sides with one transparent glassor plastic viewing side. The box is illuminated using anincandescent lightbulb. The viewing area shall be slightlysmaller than the vapor retarder specimen so that holes ordegradation caused by aging are readily visib
12、le.6.3 Cotton Gloves.6.4 Cardboard Overhead Transparency Frames or Equiva-lent.6.5 Stainless Steel Staples.6.6 Glass or Stainless Steel Rods.7. Test Specimens7.1 From each sample cut four specimens that are largeenough to acquire water vapor permeance test specimens afterexposure. The specimens shal
13、l be cut in a manner which bestcharacterizes the roll width. Material exhibiting extraneousdamage from mishandling in shipment or during samplepreparation shall be avoided. A fifth specimen shall be cut andretained as a control. An 1134 in. (298 mm) by 1034 in. (273mm) specimen size is recommended s
14、ince this is the size of atypical overhead transparency frame, which is useful to support1This test method is under the jurisdiction ofASTM Committee C16 on ThermalInsulation and is the direct responsibility of Subcommittee C16.33 on InsulationFinishes and Moisture.Current edition approved Aug. 1, 2
15、008. Published August 2008. Originallyapproved in 1994. Last previous edition approved in 2000 as C 125894(2000).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the
16、 standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.specimens in the humidity chamber. In any case, the specimensize shall be at least 6 in. by 6 in. (152 mm by 152 mm).8. Aging Procedu
17、re8.1 Use clean cotton gloves during handling to avoidsurface contamination that may be confused with corrosion onfoil or metallized laminates.8.2 Once cut to the desired size, individually sandwich andstaple the retarder specimens between two transparency framesor equivalent. The frames help to min
18、imize curl and facilitatehandling without disturbing the specimen surface area. Num-ber the specimens 1 through 4, and retain the extra framedspecimen for later comparisons.8.3 Mount the four frames on a glass rod. This is easilyaccomplished by using a paper punch on one corner of theframes and slid
19、ing the frames onto the rod. Space the frames atleast 1 in. (25 mm) apart.8.4 Suspend the rod with frames in the humidity chamber.The specimens shall be oriented to allow air-flow parallel to thesurface.8.4.1 Carefully follow operation instructions of the testchamber to avoid surface condensation of
20、 the test specimens.Expose the specimens for 28 days at 120 6 2F (49 6 1C)and 95 % 6 2 relative humidity.8.4.2 Alternate methods of suspending specimens may beused, provided specimen to specimen contact, or contact withpotentially reactive materials, is avoided. Specimens must haveadequate airspace
21、and should never be oriented horizontally inthe cabinet.9. Evaluation9.1 At the end of 28 days, evaluate the specimens for thefollowing:9.1.1 For all products, place the specimens on the lightedbox and inspect for pinholes, large holes, or increased trans-lucency from the retained control specimen.
22、Lightly marknoteworthy areas with a felt-tip pen.9.1.2 For foil laminates also inspect the foil surface forevidence of corrosion in the form of crystalline deposits. Thisinspection is easily accomplished in a darkroom by viewing thespecimen using a flashlight held at an angle. Corrosion depositshave
23、 an iridescent appearance when viewed in this manner.9.1.3 For all products, cut one water vapor permeancespecimen from each aged piece. Specimens shall be cut fromany noteworthy areas identified during the light box inspection.Determine the water vapor permeance in accordance with thedesiccant meth
24、od of Test Methods E 96/E 96M. The watervapor permeance test temperature shall be 73 6 2F (23 61C); relative humidity shall be 50 6 2%.9.1.4 After the permeance specimen is cut, carefully removethe remaining portion of sample from the test frames andinspect for evidence of delamination.10. Report10.
25、1 The report shall include the following:10.1.1 A description of the material tested including sup-plies, type, lot number, and production date where possible,and10.1.2 Any evidence of delamination if applicable, and10.1.3 Any evidence of corrosion if applicable, and10.1.4 Any evidence of metallizat
26、ion loss if applicable, and10.1.5 Water vapor permeance after aging.11. Precision and Bias11.1 No statement is made concerning the precision and biasof the visual inspection portion of the accelerated aging ofvapor retarders for insulation, since results merely compareperformance to an unexposed con
27、trol.11.2 Refer to Test Methods E 96/E 96M for precision andbias of the water vapor permeance determination.12. Keywords12.1 corrosion; humid aging; insulation; vapor retarder;water vapor permeanceASTM International takes no position respecting the validity of any patent rights asserted in connectio
28、n with any item mentionedin this standard. Users of this standard 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
29、technical committee and must be reviewed every five years andif 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 consid
30、eration at a meeting of theresponsible technical committee, which 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 Bar
31、r Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United 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).C1258082
