1、Designation: F 2391 05Standard Test Method forMeasuring Package and Seal Integrity Using Helium as theTracer Gas1This standard is issued under the fixed designation F 2391; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year o
2、f last 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. Scope1.1 This test method includes several procedures that can beused for the measurement of overall package and seal barrie
3、rperformance of a variety of package types and package forms,as well as seal/closure types. The basic elements of this methodinclude:1.1.1 Helium (employed as tracer gas),1.1.2 Helium leak detector (mass spectrometer), and1.1.3 Package/product-specific test fixtures.1.1.4 Most applications of helium
4、 leak detection are de-structive, in that helium needs to be injected into the packageafter the package has been sealed. The injection site then needsto be sealed/patched externally, which often destroys itssaleability.Alternatively, if helium can be incorporated into theheadspace before sealing, th
5、e method can be non-destructivebecause all that needs to be accomplished is to simply detectfor helium escaping the sealed package.1.2 Two procedures are described; however the supportingdata in Section 14 only reflects Procedure B (Vacuum Mode).The alternative, Sniffer Mode, has proven to be a valu
6、ableprocedure for many applications, but may have more variabil-ity due to exactly the manner that the operator conducts the testsuch as whether the package is squeezed, effect of multiplesmall leaks compared to fewer large leaks, background heliumconcentration, package permeability and speed at whi
7、ch thescan is conducted. Further testing to quantify this proceduresvariability is anticipated, but not included in this version.1.2.1 Procedure A: Sniffer Modethe package is scannedexternally for helium escaping into the atmosphere or fixture.1.2.2 Procedure B: Vacuum Mode the helium containingpack
8、age is placed in a closed fixture. After drawing a vacuum,helium escaping into the closed fixture (capture volume) isdetected. Typically, the fixtures are custom made for thespecific package under test.1.3 The sensitivity of the method can range from thedetection of:1.3.1 Large leaks10-2Pam3/s to 10
9、-5Pam3/s (101cc/sec/atm to 10-4cc/sec/atm).1.3.2 Moderate leaks10-5Pam3/s to 10-7Pam3/s (10-4cc/sec/atm to 10-6cc/sec/atm).1.3.3 Fine leaks10-7Pam3/s to 10-9Pam3/s (10-6cc/sec/atm to 10-8cc/sec/atm).1.3.4 Ultra-Fine leak10-9Pam3/s to 10-11Pam3/s (10-8cc/sec/atm to 10-10cc/sec/atm).NOTE 1Conversion f
10、rom cc/sec/atm to Pam3/s is achieved by mul-tiplying by 0.1.1.4 The terms large, moderate, fine and ultra-fine are rela-tive terms only and do not imply the acceptability of any leakrate. The individual application dictates the level of integrityneeded. For many packaging applications, only “large l
11、eaks”are considered unacceptable and the ability to detect smallerleaks is immaterial. All leak rates referred to in this method arebased on conversion of actual conditions (based on partialpressure of helium) to one atmosphere pressure differential andstandard temperature conditions.1.5 The method
12、may have applicability to any package type:1.5.1 Flexible,1.5.2 Semi-rigid, or1.5.3 Rigid.1.6 The sensitivities reported in the supporting data for thismethod pertain to the detectability of helium emanating fromthe sample and are not a function of the packaging form.1.7 The method is not applicable
13、 to breathable or porouspackaging.1.8 The results obtained can be qualitative, semi-quantitative or quantitative depending on the procedure used.1.9 Test fixture design is not within the scope of this methodexcept to note that different designs will be needed for differentapplications (which have di
14、fferent package types and packageintegrity requirements). Furthermore, the fixture selection anddesign will be based on where the testing is to be conductedwithin the manufacturing process (in other words, qualitycontrol versus research).1This test method is under the jurisdiction of ASTM Committee
15、F02 on FlexibleBarrier Materials and is the direct responsibility of Subcommittee F02.40 onPackage Integrity.Current edition approved April 1, 2005. Published May 2005.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.1.10 This standar
16、d 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. Referenced Documents2.1 ASTM
17、 Standards:2D 996 Terminology of Packaging and Distribution Environ-mentsD 3078 Test Method for Determination of Leaks in FlexiblePackaging by Bubble EmissionD 4991 Test Method for Leakage Testing of Empty RigidContainers by Vacuum MethodE 432 Guide for Selection of a Leak Testing MethodE 479 Guide
18、for Preparation of a Leak Testing SpecificationE 493 Test Methods for Leaks Using the Mass SpectrometerLeak Detector in the Inside-Out Testing ModeE 498 Test Methods for Leaks Using the Mass SpectrometerLeak Detector or Residual Gas Analyzer in the Tracer ProbeModeE 499 Test Methods for Leaks Using
19、the Mass SpectrometerLeak Detector in the Detector Probe ModeE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE 1603 Test Methods for Leakage Measurement Using theMass Spectrometer Leak Detector or Residual Gas Analyzerin the Hood ModeF17 Terminology R
20、elating to Flexible Barrier MaterialsF 1327 Terminology Relating to Barrier Materials for Medi-cal Packaging2.2 Other Documents:Principal author L. Kirsch, et al - (shown in referenceAppendix X1 as literature references 1, 2, 3 and 5)Principal author L. Nguyen, et al - (shown in referenceappendix I
21、at literature reference 4)Co-authors include C. Moeckly, L. Nguyen, R. Gerth, W.Muangsiri, R. Scheire, D. M. Guazzo, L. Kirsch, G.Schmitt,A. Kirsch, M. Koch, T. Wertli, M. Lehman and G.Schramm.3. Terminology3.1 General Term Definitions For definitions used in thisstandard see Terminology D 996, Term
22、inology F17and Ter-minology F 1327.3.2 Specific Term Definitions3.2.1 actual helium leak rate (AHLR)Measured heliumleak rate (MHLR) signal level adjusted to a driving force of100 % concentration at 101 KPa (1.0 atmosphere), absolute.3.2.2 breathable/porous packagingPackages, in whole orin part, that
23、 intentionally allow gases/vapors to flow freely intoand out of the package. (See also Terminology F 1327)3.2.3 fine leaksFor the purpose of this test method, leaksthat exhibit gas/vapor leak rates between 1310-7Pam3/s to10-9Pam3/s (1310-6cc/sec/atmosphere to 1310-8cc/sec/atmosphere).3.2.4 flexible
24、packagingPackages (typically, pouches, sa-chets, and bags) constructed of materials that are readilybendable. (See also Terminology Method F17)3.2.5 impermeable packagingPackages constructed ofmaterials (typically metal or glass) that prevent gases/vaporsfrom flowing into or out of the package.3.2.6
25、 large leaksFor the purpose of this test method, leaksthat exhibit gas/vapor leak rates between 1310-2Pam3/s to1310-5Pam3/s (13101cc/sec/atm to 1310-4cc/sec/atmosphere).3.2.7 measured helium leak rate (MHLR)Helium signallevel obtained based on the actual helium concentration in thepackage.3.2.8 mode
26、rate leaksFor the purpose of this test method,leaks that exhibit gas/vapor leak rates between 1310-5Pam3/sto 10-7Pam3/s (1310-4cc/sec/atmosphere to 1310-6cc/sec/atmosphere).3.2.9 outgassingThe release of adsorbed, absorbed orphysically trapped gas from a surface of structure.3.2.10 pass/fail criteri
27、onThe predeterminedAHLR abovewhich the package being tested is considered defective and,therefore, unacceptable.3.2.11 permeable packagingPackages, in whole or inpart, that allow gases/vapors to flow into and out of a packagevia diffusion controlled process.3.2.12 semi-rigid packagingPackages (typic
28、ally, thermo-formable, or cold-formable materials) that are formed intoblisters or trays, with associated lidding materials applied asthe closure means.3.2.13 ultra fine leaksFor the purpose of this test method,leaks that exhibit gas/vapor leak rates between 1310-9Pam3/sto 1310-11Pam3/s (1310-8cc/se
29、c/atmosphere to 1310-10cc/sec/atmosphere).3.2.14 virtual leakA source of detectable tracer gas otherthan from a defect of the seal or package. Such a virtual leakmay be the result of membrane permeability, surface desorp-tion or release of trapped gas.4. Summary of Test Procedures4.1 There are two b
30、asic test procedures contained in this testmethod:4.1.1 Procedure ASniffer Mode.4.1.2 Procedure BVacuum Mode.4.2 Both of these test procedures require the package undertest to have helium at some measurable level on the side of thepackage opposite the leak detector sensor (typically, the insideof th
31、e package). If the package cannot, or should not be sealedwith helium inside, the test fixture used for that particular testneeds to provide a means of helium introduction at theappropriate location and the appropriate time in the test cycle.The one exception is a package with a gross leak for which
32、 avariation of the helium pressurized “back-filling” or “soaking”technique may be applicable. In all cases helium, at as high aconcentration as practicable, must be present on one side of thepackage/seal barrier element.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact
33、ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.F23910524.3 To quantify the leak rate level of a given package, orpackage seal, the partial pressure driving force of the heliummust be known
34、. Therefore, an important part of the process ofconducting a leak rate test is the determination of the concen-tration of helium at one atmosphere (absolute pressure) presentduring the test. Generally speaking, some type of calibratedresidual gas analyzer (RGA) device will need to be utilized forthi
35、s step.4.4 The MHLR (measured helium leak rate) values will bedetermined based on a comparison to the calibration, referencestandard employed. It is subsequently adjusted to an AHLR(actual helium leak rate), which is based on the actual packagehelium partial pressure (see 4.5).4.5 If appropriate, th
36、e AHLR value for the package undertest can be compared to the pre-established Pass/Fail criterionfor that specific product/package to ascertain acceptability (perestablished specification requirements).5. Significance and Use5.1 The vacuum, bubble test method, as described in TestMethod D 3078, and
37、various other leak detection methodsdescribed elsewhere (Test Method D 4991, Guide E 432, GuideE 479, Test Method E 493, Test Method E 498, Test MethodE 499, and Test Method E 1603) have been successfully usedwidely in various industries and applications to determine thata given package is or is not
38、 a “leaker.” The sensitivity of anyselected leak test method has to be considered to determine itsapplicability to a specific situation.5.2 The procedures presented in this test method allow theuser to carry out package and seal integrity testing withsufficient sensitivity to quantify seals in the p
39、reviously definedmoderate to very fine seal ranges.5.3 By employing seal-isolating leak testing fixtures, pack-ages constructed of various materials can be tested in the fullrange of seal performance requirements. Design of thesefixtures is beyond the scope of this method.5.4 These seal/package inte
40、grity test procedures can beutilized as:5.4.1 A design tool,5.4.2 For tooling qualification,5.4.3 Process setup,5.4.4 Process validation tool,5.4.5 Quality assurance monitoring, or5.4.6 Research and development.6. Interferences6.1 The introduction of the helium tracer gas to the non-sensor side of t
41、he package (typically the inside) can be doneeither before or after sealing.6.2 Some helium may be present in the testing environmentwhich may interfere with results. Care must be taken toeliminate background helium with ventilation, location ofsupply cylinders, proper sample isolation fixturing or
42、othermeans.6.3 When attempting to detect very small leaks, care mustbe taken to eliminate, minimize, or compensate for falsereadings from “virtual leak” sources, particularly trappedhelium in seal areas.6.4 The permeation of the package by helium does notindicate a leak. Care must be taken to unders
43、tand the level ofpermeation to prevent misinterpretation of results. Similarly,some materials may absorb helium and yield false results whentested. Outgassing of these materials may greatly increase testtime.6.5 These procedures, particularly when detecting moderateto very fine leaks, should be carr
44、ied out using calibratedexternal leak standards.6.6 Physical/mechanical constraints are generally requiredfor flexible and semi-rigid packages to avoid vacuum-inducedseal failures. Properly constrained packages can mean thedifference between success and failure in carrying out the testprocedure.7. A
45、pparatus7.1 A helium leak detector (mass spectrometer). An oil-freevacuum system is recommended with hard vacuum test portand sniffer probe attachment (as appropriate for a specificapplication) for those applications where the testing area needsto be maintained as a clean environment, or where the r
46、eleaseof vacuum pump oil could lead to product contamination, orboth.7.2 External calibrated leaks (calibrated within the last 12months; 6 months is recommended). At least three rangesshould be covered depending on the application; typically1310-6,1310-7and 1310-8cc/s/atm. Alternatively, morecalibra
47、ted leaks may be used.7.3 A vacuum chamber, with custom-design constraints thatare package-specific (sniffer mode testing may not require avacuum chamber).7.4 A headspace analyzer device for measuring the partialpressure of (concentration at 1 atm pressure) helium insamples.7.5 The method to introdu
48、ce helium into the package needsto be developed specifically for the package under test.Techniques and devices that have been successfully employedinclude:7.5.1 Pre-filling of packages using an on-line floodingfixture (helium introduced to package headspace prior tosealing).7.5.2 Post-filling of pac
49、kages by injection of helium into thesealed package. A fine gage syringe needle and flow-controlledhelium gas supply, followed by sealing of the puncture site hasbeen found to work well.7.6 An enclosure for sniffer mode testing seals/packages formoderate, fine, or ultra-fine leaks in a lowered helium back-ground environment may be found necessary to reduce infer-ence of background helium.7.7 A data acquisition and analysis device is optional, butrecommended, for recording, or calculating, or both the mea-sured helium leak rates (MHLR), helium
