Standard Test Method for Nondestructive Detection of Leaks ...

1 Designation: F 2338 05 Standard Test Method forNondestructive Detection of Leaks in Packages by VacuumDecay Method1 This 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 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 Packages Packages that can be nondestructivelyevaluated by this test Method Rigid and semi-rigid non-lidded Trays or cups sealed with porous barrier Rigid, nonporous Flexible, nonporous packages ( ). Detected This test Method is capable of detect-ing package Leaks using an absolute or differential pressuretransducer leak detector.

2 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 described below. These data are based on precision andbias confirmation 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 4 104Pa (400 mbar) using anabsolute pressure transducer test Sealed with Porous Barrier Lidding Material Hole or crack defects in the wall of the tray/cup of at least 100 m in diameter can be detected. Channel defects in the sealarea (made using wires of 125 m in diameter) can be seal bonding defects in both continuous adhesive anddot matrix adhesive package systems can be detected.

3 Slightlyincomplete dot matrix adhesive bonding defects can also bedetected. All porous barrier lidding material packages weretested at a Target Vacuum of 4 104Pa (400 mbar) using anabsolute pressure transducer test instrument. Using a calibratedvolumetric airflow meter, the sensitivity of the test for porouslidded packages is shown to be approximately 10-2Pa m3 , Nonporous Packages Hole defects of at least5 m in diameter can be detected. All rigid, nonporouspackages were tested at a target vacuum of 5 104Pa (500 mbar)using a differential pressure transducer test instrument. Using acalibrated volumetric airflow meter, the sensitivity of the testfor rigid, nonporous packages is shown to be approximately10-4Pa m3 , Nonporous Packages Such packages mayalso be tested by the vacuum decay Method using either anabsolute or differential pressure tranducer test instrument.

4 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 Results The test results are qualitative (Accept/Reject). Acceptance criteria for test results are established fromquantitative baseline vacuum decay measurements obtainedfrom control, non-leaking Value Units The values used in this testmethod are stated in SI units and are to be regarded as standardunits. Values in parentheses are for information 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 Referenced 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 Barrier MaterialsF 1327 Terminology Relating to Barrier Materials for Medi-cal Packaging3.

5 For definitions used in this test Method ,see TerminologiesD 996,F17, andF test Method is under the jurisdiction of ASTM Committee F02 on FlexibleBarrier Materials and is the direct responsibility of Subcommittee onPackage edition approved April 1, 2005. Published April 2005. Originallyapproved in 2003. Last previous edition approved in 2004 as F 2338 referenced ASTM standards , visit the ASTM website, , orcontact ASTM Customer Service at ForAnnual Book of ASTMS tandardsvolume information, refer to the Standard s Document Summary page onthe ASTM ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United by ASTM Int'l (all rights reserved);Reproduction authorized per License Agreement with Oliver Pace ().

6 Fri May 5 08:38:39 EDT of Terms Specific to This vacuum decay,n the extent of vacuumchange within the test chamber over time demonstrated by acontrol, non-leaking , non-leaking packages,n packages withoutdefects and properly sealed or closed according to manufac-turer s , nonporous packages,n packages that sig-nificantly deflect when under vacuum, and are constructed ofmalleable, nonporous materials. Examples include pouches orbags made of polymeric, foil, or laminate , nonporous packages,n packages that do notsignificantly deflect under vacuum and are constructed of solid,nonporous materials. For example, plastic bottles with screw-thread or snap-on closures are rigid, nonporous trays or cups,n trays made of materialthat retain shape upon deflection.

7 For example, thermoformedPETE or PETG trays are considered semi-rigid or mottled seals,n an 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 airflow meter,n a 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 NIST standards . The operational range of the meter should reflect thedesired limit of sensitivity for the intended leak of Test Cycle and Critical ParametersTerms For terms and abbreviations relating to the test cycleand the critical parameters for establishing accept/reject limits,seeAnnex Summary of Test The test package is placed in a test chamber to whichvacuum is applied.

8 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 packageheadspace gas being drawn out of the package through anyleaks present, plus background noise. Leak Detection requiresvacuum decay in excess of the background noise noise vacuum decay may result from packageexpansion when exposed to vacuum (flexible or semi-rigidpackages), or from residual gases inherent in the test chamberor test system Porous barrier lidded tray or cup packages are tested forleaks located in the tray or cup, and at the lidding material/trayseal junction.

9 Leaks in the porous lidding material itself cannotbe detected. When testing such packages, steps 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 lidded 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 The sensitivity of a vacuum decay leak test is a functionof several factors. Smaller Leaks can be detected with moresensitive pressure transducers, and with longer test times.

10 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 can also improve sensitivity. For example,for porous barrier lidded packages, more effective maskingtechniques will minimize background Further information on the Leak Test Theory may be foundinAnnex Significance and Leaks in medical device, pharmaceutical and foodpackages 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 consistency and integrity of After initial set-up and calibration, the operations ofindividual tests may be semi-automatic, automatic or test Method permits the non-destructive Detection of leaksnot visibly detectable.