ASTM E1560-2011 Standard Test Method for Gravimetric Determination of Nonvolatile Residue From Cleanroom Wipers .pdf

1、Designation: E1560 11Standard Test Method forGravimetric Determination of Nonvolatile Residue FromCleanroom Wipers1This standard is issued under the fixed designation E1560; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year

2、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 solventextractable nonvolatile residue (NVR) from wipers used inassemb

3、ly, cleaning, or testing of spacecraft, but not from thoseused for analytical surface sampling of hardware.1.2 The NVR of interest is that which can be extracted fromcleanroom wipers using a specified solvent that has beenselected for its extractive qualities.Alternative solvents may beselected, but

4、 since their use may result in different values beinggenerated, they must be identified in the procedure data sheet.1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3.1 ExceptionThe inch-pound units are included forinformat

5、ion only.1.4 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.2. Ref

6、erenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterE2217 Practice for Design and Construction of AerospaceCleanrooms and Contamination Controlled AreasF24 Test Method for Measuring and Counting ParticulateContamination on SurfacesF50 Practice for Continuous Sizing and Counting

7、 of Air-borne Particles in Dust-Controlled Areas and Clean RoomsUsing Instruments Capable of Detecting Single Sub-Micrometre and Larger Particles2.2 Military Standards:3MIL-STD-1916 Acceptance on Zero Sampling Inspection2.3 Federal Standards:3Fed. Std. 209E Airborne Particulate Cleanliness Classes i

8、nCleanrooms and Clean Zones42.4 Other Documents:IEST-RP-CC001 HEPA and ULPA Filters5,6IEST-RP-CC005 Gloves and Finger Cots Used in Clean-rooms and Other Controlled Environments4ISO 14644-1 Cleanrooms and Associated Controlled Envi-ronments, Classification of air cleanliness7ISO 14644-2 Cleanrooms an

9、d Associated Controlled Envi-ronments, Specifications for testing and monitoring toprove continued compliance with ISO 14644-153. Terminology3.1 Definitions:3.1.1 contaminantunwanted molecular or particulate mat-ter that could affect or degrade the performance of thecomponents on which they are depo

10、sited.3.1.2 contaminationa process of contaminant transport oraccretion or both.3.1.3 environmentally controlled areacleanrooms, cleanfacilities, controlled work areas, and other enclosures that aredesigned to protect hardware from contamination. Cleanlinessis achieved by controlling airborne partic

11、ulate matter, tempera-ture, relative humidity, materials, garments, and personnelactivities. Guidelines for controlled areas can be found inPractice E2217.1This test method is under the jurisdiction of ASTM Committee E21 on SpaceSimulation and Applications of Space Technology and is the direct respo

12、nsibility ofSubcommittee E21.05 on Contamination.Current edition approved Dec. 1, 2011. Published January 2012. Originallyapproved in 1993. Last previous edition approved in 2006 as E1560 06. DOI:10.1520/E1560-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Cu

13、stomer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http:/dodssp.daps.dl

14、a.mil.4Fed-Std-209E has been replaced by ISO 14644-1 and -2, but may continue tobe used by mutual agreement.5The use of Di Octyl Phthalate (DOP) in leak testing of filters or filterinstallation is not acceptable.6Available from Institute of Environmental Sciences and Technology (IEST),Arlington Plac

15、e One, 2340 S. Arlington Heights Rd., Suite 100, Arlington Heights,IL 60005-4516, http:/www.iest.org.7Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West

16、Conshohocken, PA 19428-2959, United States.3.1.4 high effciency particulate air (HEPA)a term de-scribing filters having an efficiency of 99.97 % for removal of0.3-m and larger particles. For this application, filters shallmeet the requirements of IEST-RP-CC001.4 and section 6.1 ofthis test method.3.

17、1.5 molecular contaminant (nonparticulate)may be in agaseous, liquid, or solid state. It may be uniformly or nonuni-formly distributed or be in the form of droplets. Molecularcontaminants account for most of the NVR.3.1.6 NVRthat quantity of molecular matter remainingafter the filtration of a solven

18、t containing contaminants andevaporation of the solvent at a specified temperature.3.1.7 particle (particulate contaminant)a piece of matterin a solid state, with observable length, width, and thickness.The size of a particle is defined by its greatest dimension andis expressed in m.4. Summary of Te

19、st Method4.1 A wiper to be tested is placed in a clean blankedcontainer and a measured volume of solvent is added to thecontainer.4.2 The container is placed in a heated ultrasonic cleanerand agitated by ultrasonic action for a specified period of timeand the wiper is removed from the container.4.3

20、The solvent in the container is filtered into another cleancontainer and allowed to evaporate to a low volume.4.4 The solvent is transferred to a clean pre-weighed weigh-ing dish and evaporated to constant weight.4.5 The results are expressed in milligrams/0.1 squaremeters of wiper surface area or i

21、n mg/unit mass of wiper.4.6 A control blank shall be run on all solvents, filtrationcomponents, and all other equipment associated with theanalysis. In the event that more than one determination is runthe same day, additional blanks will not be necessary, but willrely on the blank value from the fir

22、st test.4.7 NVR samples thus obtained will be saved for analysis toidentify contaminant species if a more complete analysis isnecessary.5. Significance and Use5.1 The NVR obtained by this test method is that amountwhich is available for release by wipers in normal use.5.2 Evaporation of the solvent

23、at the stated temperature is toquantify the NVR that can be expected to exist at roomtemperature, since the slight difference between room tempera-ture and test temperature has not been shown to result insignificant variances.5.3 This test method may be more aggressive than necessaryfor the evaluati

24、on of wipers that will be restricted to dry useonly.5.4 Numerous other methods are being used to determineNVR. This test method is not intended to replace test methodsused for other applications.6. Apparatus and Materials6.1 Unidirectional airflow work station, 100 % exhaust forhandling solvents. Mu

25、st meet the particulate air cleanlinessClass 5 (100), or better in accordance with ISO 14644-1 andISO 14644-2 (Fed-Std-209), latest revision when tested inaccordance with Practice F50. HEPA filters in the work stationmust not have been tested with Di-Octyl Phthalate (DOP) atany time. Temperature sha

26、ll be controlled within a range of 20to 25C and relative humidity to less than 60 %.6.2 Analytical balance, 0.01-mg readability, 0.1-mg preci-sion. Capacity to be determined by user.6.3 Vacuum filtration system, 25-mm diameter, consisting ofa membrane filter funnel and vacuum pump that will provide

27、apressure of 250 Torr (20-in. Hg vac.). Other size filtrationsystems may be used as needed. All items that will come incontact with solvents during analysis shall be of glass, stainlesssteel, or other material that will not affect the analysis viainduced contamination. Any house vacuum system may be

28、used.6.4 Solvent resistant membrane filters, Fluorocarbon,25-mm diameter, 0.2-m nominal pore size.8The use ofsupported membrane filters is not recommended because ofpossible adverse effects of the solvent on the support media.6.5 Teflon-coated tweezers, or hemostat, unserrated tips.6.6 Beakers, low

29、form glass, 500 ml.6.7 Laboratory detergent, liquid.6.8 Methanol, Reagent grade, A.C.S.6.9 Acetone, Reagent grade, A.C.S.6.10 Deionized water, organic free, Type II per Specifica-tion D1193 with a minimum resistivity of 1.0 MV-cm.6.11 Gloves,9Barrier-type, low particle-generating, low out-gassing, p

30、er IEST RP-CC005.6.12 NVR solvent, Must be verified to contain no more than0.35-mg NVR per 300-mL solvent (0.12 mg per 100 mL) whentested in accordance with Section 8 of this test method.NOTE 1A solvent should be selected that is representative of theservice conditions of the wiper. The solvent used

31、 must be recorded in thetest report. Historically, a solvent consisting of three parts 1,1,1 trichlo-roethane and one part ethanol v/v has been used. 1.1.1 trichloroethane isan ozone depleting substance that is no longer available. Examples ofsolvents currently used are acetone, ethyl acetate, ethyl

32、 alcohol, isopropylalcohol, hexane, and the azeotrope of ethyl acetate/cyclohexane. Ethylalcohol and isopropyl alcohol are the least effective at removing NVR butare used when they reflect actual solvent usage in service.NOTE 2In the event that the solvent does not meet the required puritylevel, it

33、may be necessary to triple distill it, keeping the temperature of thevapor phase of the distillate no more than 0.2C higher than the boilingpoint of the solvent. Higher temperatures will result in the “carryover” ofheavier fractions in the vapor phase, which will cause the solvent to failthe require

34、d purity tests.8Nuclepore Corp. PTFE Filinert membrane filter, P/N 130606, and MilliporeCorp. Fluoropore filter, P/N 02500 have been found to be satisfactory. Otherequivalent, solvent-resistant filters may be used. Larger diameter filters to fit largerfilter assemblies are acceptable.The sole source

35、 of supply of the apparatus known to the committee at this timeis Nuclepore Corp. If you are aware of alternative suppliers, please provide thisinformation to ASTM International Headquarters. Your comments will receivecareful consideration at a meeting of the responsible technical committee,1whichyo

36、u may attend.9Gloves are necessary to protect the analyst from exposure to NVR solvent andto minimize the possibility of introducing any artifacts from the analyst into thesample. Must be resistant to the solvent used and provide a firm grip on items beinggrasped by the gloves.E1560 1126.13 Ultrason

37、ic tank, 5.7-L capacity nominal, with heatercapable of maintaining a temperature of 35 6 2C, and coverto position beakers in tank. Other sizes may be used.6.14 Evaporating dishes, aluminum foil, 43-mm diameter,or acceptable equivalent.6.15 Drying oven (desiccator), cleanroom compatible,stainless ste

38、el interior.7. Preparation of Equipment7.1 All operations shall be performed in a work station inaccordance with section 6.1.7.2 Wash all glassware, filter funnels, weighing dishes, andassociated tools in a 3 % solution of liquid detergent indeionized water. Rinse with deionized water for a period o

39、f 1minute, followed by rinsing with acetone or methanol, thenwith the NVR solvent described in section 6.10. Dry in acleaned oven for1hat35C, remove, and store in a desiccatoruntil used.7.3 All items, such as glassware, funnels, and so forth, thatwill come in contact with the NVR solvent during anal

40、ysis,will be blanked in accordance with Section 8 of this testmethod before use.8. NVR and System Blank8.1 The NVR of the solvent, and all glassware or other itemsthat will come in contact with the solvent during the analysis,shall be determined before use. The only exception is whenseveral tests ar

41、e to be run consecutively, in which case, theblank only needs to be determined once for a batch. It must beremembered that this solvent will absorb moisture from theatmosphere every time the storage container is opened, so largequantities should not be processed at one time.8.1.1 Pour 300 mL of solv

42、ent into a 500-mL beaker cleanedper 7.2.8.1.2 Perform analysis per Section 9.8.1.3 The NVR blank shall be less than 0.35 mg per 300mL.8.1.4 Record the results of the blank analysis on the testreport form.8.1.5 Solvents that do not meet the NVR requirements maybe redistilled and retested.8.1.6 Only v

43、erified clean, non-contaminating metals, glass,or fluorocarbon containers are acceptable for storage ofblanked solvent.9. Procedure9.1 All operations shall be performed in a work station inaccordance with section 6.1.9.2 Assemble the filtration assembly according to manufac-turers instructions.9.3 W

44、hen reporting results on the basis of mg per unit area,place enough wipers to provide a combined surface area of 0.1m2, minimum, in a precleaned 500-mL beaker.10For example,a wiper measuring 6 by 6 in. will have a surface area of 36 in.2,thus requiring four wipers to provide the necessary surfaceare

45、a. Do not cut wipers to simplify calculations or for any otherpurpose. The wipers must be tested as received from thesupplier. (No attempt shall be made to determine the surfacearea of each individual fiber in a woven product.) Whenreporting results on the basis of mg per unit mass, weigh asample of

46、 the wipers to be tested (similar to above sample size)to an accuracy of 0.1 mg. Place in beaker as above.9.4 Add 300-mL blanked NVR solvent to beaker. Coverbeaker with a watchglass to minimize contamination of sampleby fallout.NOTE 3Wipers larger than 0.1 m2will require 500 mL of solvent toensure c

47、omplete wetting of the sample.9.5 Place beaker in ultrasonic tank that has been filled withfluid heated to 35 6 2C and install tank cover to position thebeaker in the tank. Typically, the fluid used is D.I. water.9.6 Agitate for 30 min. This agitation is necessary to ensurethat all available NVR is

48、contacted by solvent and removedfrom the wiper being tested.9.7 Remove beaker from tank and extract wiper(s) usingprecleaned tongs. Hold wipers over the beaker until drippingceases. Place damp wiper on a tray or rack to dry. When theitem is dry, as determined by a lack of solvent odors, it will bepl

49、aced in a clean Nylon plastic envelope, and saved for futurereference, or discarded at the option of the analyst. No furtheranalysis will be performed on this sample.9.8 Filter the solvent into a precleaned and blanked beakerthat has been installed in the filtration assembly.119.9 When all the solvent has been filtered, rinse the filterassembly with solvent (exact volume of rinse is not critical).The filter membrane may be removed from the filter assemblyand analyzed in accordance with Appendix X1 to determineparticle release from the wipers.9.10 Place the be