1、Designation: E2649 12Standard Test Method forDetermining Argon Concentration in Sealed Insulating GlassUnits Using Spark Emission Spectroscopy1This standard is issued under the fixed designation E2649; the number immediately following the designation indicates the year oforiginal adoption or, in the
2、 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.1. Scope1.1 This test method covers procedures for using a sparkemission spectroscope to determine
3、the concentration of argongas in the space between the lites of a sealed insulating glassunit.1.2 This is a non-destructive test method.1.3 This test method shall be used only in a controlledlaboratory environment.1.4 This test method is applicable for insulating glass unitswhere argon has been adde
4、d to the sealed insulating glasscavity and the balance of the gas is atmospheric air.1.5 This test method is applicable for clear, double-glazedinsulating glass units.1.6 This test method is applicable for double-glazed insu-lating glass units with one lite having a metallic coating ortinted glass,
5、or both, and with clear glass as the other lite.1.7 This test method is applicable for triple-glazed insulat-ing glass units only when the center lite of glass has a metalliccoating (either low emissivity (low E) or reflective) and both ofthe other lites are clear glass.1.8 This test method also inc
6、ludes a procedure for verifyingthe accuracy of the readings of the test apparatus.1.9 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are mathematicalconversions to inch-pound units that are provided for informa-tion only and are not considered standa
7、rd.1.10 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is 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. For specif
8、icwarning statements, refer to 7.1.2. Referenced Documents2.1 ASTM Standards:2C162 Terminology of Glass and Glass ProductsC717 Terminology of Building Seals and SealantsE631 Terminology of Building ConstructionsE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice fo
9、r Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE2190 Specification for Insulating Glass Unit Performanceand Evaluation3. Terminology3.1 For definitions of terms found in this test method, referto Terminologies C162, C717, and E631.3.2 Definitions of Terms Specific to
10、 This Standard:3.2.1 sealed insulating glass unitan assembled unit, com-prising sealed lites of glass separated by dehydrated space(s),normally intended for clear vision areas of buildings.4. Summary of Test Method4.1 The spark emission spectroscope is placed against theglass surface of a sealed ins
11、ulating glass unit in a prescribedmanner. A high voltage, at low current, is applied to the glasssurface. This voltage creates a spark which induces a plasmafrom the gas molecules inside the test specimen. This causeslight emissions (photons) of characteristic wavelengths. Theinstrument then collect
12、s the photons and analyzes them byspark emission spectroscopy. The resulting spectrum is com-pared to calibration data internal to the instrument to determinethe concentration of argon inside the unit.5. Significance and Use5.1 This test method is intended to provide a means fordetermining the conce
13、ntration of argon in sealed insulating1This test method is under the jurisdiction of ASTM Committee E06 onPerformance of Buildings and is the direct responsibility of Subcommittee E06.22on Durability Performance of Building Constructions.Current edition approved April 1, 2012. Published May 2012. Or
14、iginallyapproved in 2009. Last previous edition approved in 2009 as E2649 09. DOI:10.1520/E2649-09.2For 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 standards Docu
15、ment Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.glass units under controlled conditions in compliance with theapparatus manufacturers instructions.5.2 This is a non-destructive test method in that
16、 the edgeseal of the test specimen is not breached in order to determinethe argon gas concentration. However, damage to some glasscoatings on the inner surfaces of the glass can occur.5.3 This test method has been developed based on datacollected in a controlled laboratory environment.5.4 The device
17、 shall be used to determine the argon gasconcentration in insulating glass units in a controlled labora-tory environment. Refer to 12.3.5.5 This test method may be used to determine the argon gasconcentration before, during, or after the insulating glass unit issubjected to durability tests.5.6 The
18、accuracy of the test method is dependent upon theaccuracy of the Spark Emission Spectroscope. When theconcentration of the argon being measured is below certainlevels, this test method is not applicable. See the spectroscopemanufacturers literature for recommended levels of accuracyof a given model.
19、6. Apparatus6.1 Spark Emission Spectroscope:6.1.1 The apparatus employs a high voltage, at low current,source and employs spark emission spectroscopy.6.1.2 The head of the spark emission spectroscope containsan electrode which is used to apply the voltage to the glasssurface of the test specimen. It
20、 also contains a light collectorwhich transmits light emissions to a spectrometer for process-ing.6.1.3 Different models3of the spark emission spectroscopeshall be acceptable provided that new models demonstrateaccuracy limits as defined in Section 10.6.2 Specimen Stand:6.2.1 The test specimen shall
21、 be supported in a verticalposition or up to 30 off vertical position.6.2.2 If necessary, a stand is used to support the testspecimens. For example test stands, see Fig. 1 and Fig. 2.6.3 Background:6.3.1 A non-reflective black background shall be positionedbehind the test specimen. Examples of backg
22、round materialsinclude photographic black fabric and black closed-cell foam.7. Hazards7.1 WarningThe high voltage of the spark emissionspectroscope used in this test method can be harmful. Appro-priate protective measures shall be observed. Refer to theinstrument manufacturers instruction manual.8.
23、Test Specimens8.1 Any sealed insulating glass unit that allows the sparkemission spectroscope to excite the gas present in the airspacecan be tested using this test method.8.2 Typically, test specimens are 355 mm 3 505 mm (14 in.3 20 in.) sealed insulating glass units constructed using onelite of 4
24、mm (532 in.) clear uncoated glass, a 12 mm (12 in.) air3This method was based on use of the Gasglass 1002 device (the wand model).As of this writing, there are other models of the device which include V1 and V2(handheld models). The sole source of supply of these apparatuses known to thecommittee at
25、 this time is Sparklike, Ltd., Srkiniementie 5 C6, 00210 Helsinki,Finland, http:/. If you are aware of alternative suppliers, pleaseprovide this information to ASTM International Headquarters. Your comments willreceive careful consideration at a meeting of the responsible technical committee,1which
26、you may attend.FIG. 1 Example of Test StandFIG. 2 Another Example of Test StandE2649 122space, and one lite of 4 mm (532 in.) coated low E glass.Variations in the specimen construction may require a correc-tion. See the instrument manufacturers instruction manual forfurther information.9. Calibratio
27、n9.1 Adjustment of the instrument is recommended to beperformed only by the manufacturer of the instrument or anauthorized service representative. The user shall verify theaccuracy of the instrument readings using Section 10.10. Verification10.1 Verification of the accuracy of the instrument reading
28、sshall be performed by the user.10.2 Verification Specimens:10.2.1 The verification specimens shall be comprised of twolites of 4 mm glass, and a 12.0 mm 6 0.8 mm cavity. One ofthe lites of glass shall have a metallic, low emissivity coatingon its cavity facing surface. Specimen size is suggested to
29、 be350 mm 3 350 mm.10.2.2 Follow the instrument manufacturers instructionmanual for gas filling of verification specimens. Fill theverification specimens with reference gas mixtures accordingto 10.3.NOTE 1Different models3of the spark emission spectroscope mayhave different requirements for gas fill
30、ing of verification specimens.Consult the manufacturers instruction manual specific to the model ofuse.10.3 Reference Gas Mixtures:10.3.1 At least two reference gas mixtures that containknown percentages of argon and atmospheric air are requiredfor verification. For increased confidence in the measu
31、rementsover the capability range of the instrument, additional refer-ence gas mixtures are recommended.10.3.2 The first reference gas mixture shall have an argonconcentration of approximately 90 %.10.3.3 The second reference gas mixture shall have an argonconcentration of approximately 80 %.10.3.4 I
32、f the user has defined a specific argon gas concen-tration, then a third reference gas mixture is recommended atthe defined argon concentration.NOTE 2Suitable gas mixtures can be obtained with a certificate ofanalysis of the mixture from commercial gas suppliers. The accuracy ofthe results of this t
33、est method depends on the accuracy of the certifiedreference gas mixtures.10.4 Verification Procedure:10.4.1 Not less than five readings shall be taken on eachverification specimen following the procedures outlined in theinstruction manual of the spark emission spectroscope andfollowing Sections 11-
34、13 of this test method. The average ofthe readings is recorded as the verification specimen value.10.4.2 The verification specimen value shall not differ fromthe reference gas mixture value by more than 2 %.10.4.3 Frequent verification of the instrument shall beperformed. Users of the instrument sha
35、ll establish the fre-quency of verification.11. Conditioning11.1 The sealed insulating glass units shall be sealed for aminimum of four weeks from date of manufacture to allow forequilibration of the gas before testing.NOTE 3It takes time for the argon gas to equilibrate in any sealedinsulating glas
36、s unit. This is particularly important in units using a tubularor porous spacer and in units containing interior components such astubular or porous muntin bars. There can also be significant laminarstratification of the gasses inside the air space immediately following gasfilling. Performing this t
37、est before a unit has equilibrated could produceresults that are measurably different than the actual argon gas concentra-tion. Some labs have found that mixing of the fill gas into the hollow tubespacer of an insulating glass unit can occur within 24 h. This will varybased on unit construction and
38、gas filling methods.12. Procedure12.1 Turn on the instrument and allow it to warm up for atleast 30 min.FIG. 3 Orientation of Sensor on Wand ModelFIG. 4 Orientation of Sensor on Hand ModelE2649 12312.2 Orient the test specimen vertically against a darkbackground. Alternatively, place the test specim
39、en on a stand.(See Fig. 1.)12.3 Maintain controlled conditions in the room that in-clude:12.3.1 No direct sunlight,12.3.2 No high intensity lamps in close proximity to thespecimens, and12.3.3 Air temperatures of 23 6 3C (73 6 5F).12.4 For double-pane specimens that contain a metalliccoating (either
40、low E or reflective), this coated lite shall beplaced against the dark background. A non-coated lite must befacing the instrument. For triple-pane specimens both outerlites are required to be clear glass and the middle lite must havea coating on one surface.NOTE 4Sealed insulating glass units with m
41、etallic coatings on bothlites (both outer lites for triple-glazed units) cannot be tested with this testmethod.12.5 Orient the sensor head so that the optical sensor isabove the electrode in the face plate of the head. For the wandmodel, this puts the button/switch for the spark up at12 oclock. (See
42、 Fig. 3.) For the compact handheld model, therequired orientation is shown in Fig. 4.12.6 Locate the sensor head on the glass surface oppositethe black background. The edge of the sensor head shall be atthe inside edge of the insulating glass spacer of the testspecimen. (See Fig. 5.)12.7 Press the s
43、ensor head evenly against the glass so thatthe sensor head is perpendicular to the glass surface.12.8 Press the button on the instrument to take a reading.12.8.1 If the spark does not arc between glass Surfaces Twoand Three on specimens without a metallic coating, place agrounding device against the
44、 glass surface opposite the sensorhead and repeat 12.6 and 12.7. Examples of grounding devicesinclude a finger, hand, or metal contact point. (See Fig. 6.) Ablack background shall be behind the grounding device toeliminate extraneous light from entering the spectrometer.12.9 Observation of the follo
45、wing events is essential. If anyof these events occurs during the sparking operation, reject thereading and take another reading:12.9.1 Changes in ambient lighting,12.9.2 Movement of the sensor head,12.9.3 Inconsistent or excessive sound from the spark ascompared to typical sounds from previous meas
46、urements,12.9.4 Spark does not jump the gap in the test specimen forthe duration of the “buzzing” sound from the instrument, and12.9.5 For further information on these operational obser-vations, see the instrument manufacturers instruction manual.12.10 Repeat 12.7-12.9 four more times for a total of
47、 fivereadings. After the third reading, relocate the sensor head bymoving it along the insulating glass spacer approximately 75 to100 mm (3 to 4 in.) from the original position.12.11 Record all five readings.13. Calculation of Results13.1 Calculate and record the average and standard devia-tion for
48、the data points. Report the calculated value rounded tothe nearest whole percent.NOTE 5The terms average and standard deviation are commonmathematical terms and are found as functions in most spread sheetprograms.14. Precision and Bias14.1 The precision of this test method is based on aninterlaborat
49、ory study of ASTM E2649 09 conducted in 2011.Seven laboratories tested a total of thirteen different materialsin triplicate. Every “test result” represents an individual deter-mination. Practice E691 was followed for the analysis of thedata; the details are given in ASTM Research Report No.E06-1003.44Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:E06-1003.FIG. 5 Positioning Sensor Head Near Edge of GlassE2649 12414.1.1 Repeatability Limit (r)Two test results obtaine
