1、Designation: F 2338 07Standard Test Method forNondestructive Detection of Leaks in Packages by VacuumDecay Method1This standard is issued under the fixed designation F 2338; 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 Test PackagesPackages that can be nondestructivelyevaluated by this test method include:1.1.1 Rigid and semi-rigid
3、 non-lidded trays.1.1.2 Trays or cups sealed with porous barrier liddingmaterial.1.1.3 Rigid, nonporous packages.1.1.4 Flexible, nonporous packages (see 1.2.4).1.2 Leaks DetectedThis test method is capable of detect-ing package leaks using an absolute or differential pressuretransducer leak detector
4、. The sensitivity of a test is a functionof the sensitivity of the transducer, the package design, thedesign of the package test fixture, and critical test parametersof time and pressure. Types and sizes of leaks that may bedetected for various package systems, as well as test sensitivi-ties are des
5、cribed below. These data are based on precision andbias confirmation studies.1.2.1 Trays or Cups (Non-lidded)Hole or crack defects inthe wall of the tray/cup of at least 50 m in diameter can bedetected at a Target Vacuum of 4104Pa (400 mbar) using anabsolute pressure transducer test instrument.1.2.2
6、 Trays Sealed with Porous Barrier Lidding MaterialHole or crack defects in the wall of the tray/cup of at least 100m in diameter can be detected. Channel defects in the sealarea (made using wires of 125 m in diameter) can be detected.Severe seal bonding defects in both continuous adhesive anddot mat
7、rix adhesive package systems can be detected. Slightlyincomplete dot matrix adhesive bonding defects can also bedetected. All porous barrier lidding material packages weretested at a Target Vacuum of 4104Pa (400 mbar) using anabsolute pressure transducer test instrument. Using a calibratedvolumetric
8、 airflow meter, the sensitivity of the test for porouslidded packages is shown to be approximately 10-2Pam3s-1.1.2.3 Rigid, Nonporous PackagesHole defects of at least5 m in diameter can be detected. All rigid, nonporouspackages were tested at a target vacuum of 5104Pa (500 mbar)using a differential
9、pressure transducer test instrument. Using acalibrated volumetric airflow meter, the sensitivity of the testfor rigid, nonporous packages is shown to be approximately10-4Pam3s-1.1.2.4 Flexible, Nonporous PackagesSuch packages mayalso be tested by the vacuum decay method using either anabsolute or di
10、fferential pressure tranducer test instrument. Theinstrument should be selected based on the leak test sensitivitydesired. Sensitivity data for flexible packages were not in-cluded in the precision and bias studies, although the use ofvacuum decay for testing such packages is well known.1.3 Test Res
11、ultsThe test results are qualitative (Accept/Reject).Acceptance criteria for test results are established fromquantitative baseline vacuum decay measurements obtainedfrom control, non-leaking packages.1.4 Standard Value UnitsThe values used in this testmethod are stated in SI units and are to be reg
12、arded as standardunits. Values in parentheses are for information only.1.5 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 th
13、e applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 996 Terminology of Packaging and Distribution Environ-mentsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodF17 Terminology Relating to Flexible Barrie
14、r PackagingF 1327 Terminology Relating to Barrier Materials for Medi-cal Packaging33. Terminology3.1 DefinitionsFor definitions used in this test method,see Terminologies D 996, F17, and F 1327.3.2 Definitions of Terms Specific to This Standard:1This test method is under the jurisdiction of ASTM Com
15、mittee F02 on FlexibleBarrier Packaging and is the direct responsibility of Subcommittee F02.40 onPackage Integrity.Current edition approved Oct. 1, 2007. Published October 2007. Originallyapproved in 2003. Last previous edition approved in 2005 as F 2338 05.2For referenced ASTM standards, visit the
16、 ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19
17、428-2959, United States.3.2.1 baseline vacuum decay, nthe extent of vacuumchange within the test chamber over time demonstrated by acontrol, non-leaking package.3.2.2 control, non-leaking packages, npackages withoutdefects and properly sealed or closed according to manufac-turers specifications.3.2.
18、3 flexible, nonporous packages, npackages that sig-nificantly deflect when under vacuum, and are constructed ofmalleable, nonporous materials. Examples include pouches orbags made of polymeric, foil, or laminate films.3.2.4 rigid, nonporous packages, npackages that do notsignificantly deflect under
19、vacuum and are constructed of solid,nonporous materials. For example, plastic bottles with screw-thread or snap-on closures are rigid, nonporous packages.3.2.5 semi-rigid trays or cups, ntrays made of materialthat retain shape upon deflection. For example, thermoformedPETE or PETG trays are consider
20、ed semi-rigid trays.3.2.6 spotty or mottled seals, nan incomplete adhesivebond made between a package tray or cup and porous liddingmaterial that can be visibly identified by a distinctive pattern ofdots, spotting or mottling on the tray sealing surface after thelid is removed.3.2.7 volumetric airfl
21、ow meter, na calibration tool thatcan be used to provide an artificial leak of known volumetricairflow rate into the test chamber for verification of instrumentsensitivity. Airflow meters should be calibrated to NISTstandards. The operational range of the meter should reflect thedesired limit of sen
22、sitivity for the intended leak test.3.3 Definitions of Test Cycle and Critical ParametersTermsFor terms and abbreviations relating to the test cycleand the critical parameters for establishing accept/reject limits,see Annex A1.4. Summary of Test Method4.1 The test package is placed in a test chamber
23、 to whichvacuum is applied. The chamber is then isolated from thevacuum source and an absolute or differential vacuum trans-ducer is used to monitor the test chamber for both the level ofvacuum, as well as the change in vacuum over time. Vacuumdecay, or rise in chamber pressure, is a result of packa
24、geheadspace gas being drawn out of the package through anyleaks present, plus background noise. Leak detection requiresvacuum decay in excess of the background noise level.Background noise vacuum decay may result from packageexpansion when exposed to vacuum (flexible or semi-rigidpackages), or from
25、residual gases inherent in the test chamberor test system lines.4.2 Porous barrier lidded tray or cup packages are tested forleaks located in the tray or cup, and at the lidding material/trayseal junction. Leaks in the porous lidding material itself cannotbe detected. When testing such packages, ste
26、ps are taken tophysically mask or block the porous barrier surface to preventthe migration of package gas through the porous lid. Thesesteps may require some sample preparation, depending on themasking approach required, but must be nondestructive andnoninvasive. Vacuum decay from porous barrier lid
27、ded pack-ages may potentially include background noise from gastrapped between the lidding material and the masking surface,or from transverse gas flow through the porous barrier materialitself at the lid/tray seal junction.4.3 The sensitivity of a vacuum decay leak test is a functionof several fact
28、ors. Smaller leaks can be detected with moresensitive pressure transducers, and with longer test times.Also,pressure changes can be more readily detected with smallervoid volumes between the test package and the test chamber,and with smaller test system line volumes. Steps to reducebackground noise
29、can also improve sensitivity. For example,for porous barrier lidded packages, more effective maskingtechniques will minimize background noise.NOTE 1Further information on the “Leak Test Theory” may be foundin Annex A1.5. Significance and Use5.1 Leaks in medical device, pharmaceutical and foodpackage
30、s may result in the ingress of unwanted gases (mostcommonly oxygen), harmful microbiological or particulatecontaminants. Package leaks may appear as imperfections inthe package components themselves or at the seal juncturebetween mated components. The ability to detect leaks isnecessary to ensure co
31、nsistency and integrity of packages.5.2 After initial set-up and calibration, the operations ofindividual tests may be semi-automatic, automatic or manual.The test method permits the non-destructive detection of leaksnot visibly detectable. The test method does not require theintroduction of any ext
32、raneous materials or substances, such asdyes or gases. However, it is important to physically mask orblock off any porous barrier surface of the package during thetest to prevent a rapid loss of chamber vacuum resultingprimarily from gas migration through the porous surface. Leakdetection is based s
33、olely on the ability to detect the change inpressure inside the test chamber as a result of air egress fromthe properly masked package when challenged with vacuumconditions.5.3 This test is a useful research tool for optimization ofpackage sealing parameters and for comparative evaluation ofvarious
34、packages and materials. This test method is alsoapplicable to production settings as it is rapid, non-invasiveand non-destructive, making it useful for either 100 % on-linetesting or to perform tests on a statistical sampling from theproduction operation.5.4 Leak test results that exceed the permiss
35、ible limits forthe vacuum decay test are indicated by audible or visual signalresponses, or both.6. Apparatus6.1 Vacuum Decay Leak Detection ApparatusAll vacuumdecay test systems include a test chamber with a lowercompartment (lower tooling) designed to nest the test package,and an upper lid (top to
36、oling) for closing the test chamber. Fig.1 illustrates a test chamber designed for testing packages withporous barrier lidding material. The test fixture upper lidconsists of a flexible bladder to mask the packages porousbarrier during the test cycle. Fig. 2 illustrates a test chamberdesigned for te
37、sting rigid, nonporous packages. In this case,there is no flexible bladder. For both test chamber designs, thetest chamber is connected to the vacuum decay test system.This system includes a vacuum source for establishing vacuumF2338072within the chamber at the beginning of the test cycle, and anabs
38、olute or differential pressure transducer for monitoring thelevel of vacuum as well as the pressure change as a function oftime during the test cycle. A calibrated volumetric airflowmeter may be placed in-line with the test system for verifyingthe sensitivity of a leak test.6.2 Tray Nest or Lower To
39、olingThe bottom half of the testchamber is dimensionally designed to closely nest the testpackage, while still allowing for easy gas flow around the testpackage. Without ready gas flow around the package, leakagesites can be blocked. Conversely, the larger the gap betweenthe test chamber and the tes
40、t package, the less sensitive the leaktest, as vacuum decay from package leakage will be minimizedin a larger net test chamber volume.6.3 Upper Lid or Upper ToolingThe upper lid is designedto tightly seal the closed test chamber during the vacuum cycle.6.4 Mask or BlockThe porous barrier lidding mat
41、erial ofpackages must be masked or blocked during testing to mini-mize egress of air from the package through the lidding.Various masking techniques may be used, including a testchamber designed with a flexible bladder in the upper tooling(refer to Fig. 1).6.5 Volumetric Airflow MeterAn adjustable v
42、olumetricairflow meter is placed in-line with the test chamber tointroduce an artificial leak of variable size. It is recommendedthat an airflow meter be used to verify the sensitivity of the leaktest parameters.NOTE 2Refer to Annex A2 for further information about the use of avolumetric airflow met
43、er for verifying leak test sensitivity.7. Hazards7.1 As the test chamber is closed, it may present pinch-pointhazards.8. Preparation of Apparatus8.1 The test apparatus must be started, warmed-up, andmade ready according to the manufacturers specifications.Utilities required for instrument operation
44、include electricalpower and a supply of dry, non-lubricated compressed air,according to manufacturers specifications.9. Calibration and Standardization9.1 Before test measurements are made, the apparatus mustbe calibrated. The pressure transducers, the vacuum sourcepressure gage, and the adjustable
45、volumetric airflow metermust all be calibrated according to the manufacturers recom-mended procedures and maintenance schedule.9.2 Critical test parameter settings must be established foreach package/test fixture combination. Parameters will varybased on the test package geometry and any porous barr
46、iersurfaces inherent porosity.NOTE 3Refer to Section 4 and Annex A1 for a description of criticaltest parameters.FIG. 1 Schematic of Fixture and Porous Barrier Lidded Test PackageF23380739.3 A sample population of control non-leaking packagesmust be used for selecting and optimizing critical test pa
47、ram-eters. Control packages are to be made from the same materialsand according to the same design as the test units.NOTE 4Refer to Annex A2 for information on critical test parameterselection.9.4 After critical test parameters have been selected, qualifythe ability of the test to reliably different
48、iate between knownnon-leaking and defective packages.9.5 Determine the sensitivity of the test using controlnon-leaking test packages and a calibrated volumetric airflowmeter.NOTE 5Refer to Annex A2 for information about test sensitivityverification procedures.9.6 Test qualification (see 9.4) and te
49、st sensitivity verifica-tion (see 9.5) are to be conducted frequently, typically at leastone or more times a day, preferably at the beginning of everyshift.10. Procedure10.1 Select and install the appropriately sized test chamberfor the package to be tested. Make any necessary adjustmentsto the chamber to ensure a sufficiently tight seal of the chamberlid (upper tooling) to the lower chamber package nest (lowertooling) when the test chamber is in the closed position.FIG. 2 Schematic of Fixture and Rigid, Nonporous Test PackageF233807410.2
