ASTM F2391-05(2011)
(Test Method)Standard Test Method for Measuring Package and Seal Integrity Using Helium as the Tracer Gas
Standard Test Method for Measuring Package and Seal Integrity Using Helium as the Tracer Gas
SIGNIFICANCE AND USE
The vacuum, bubble test method, as described in Test Method D3078, and various other leak detection methods described elsewhere (Test Method D4991, Guide E432, Guide E479, Test Method E493, Test Method E498, Test Method E499, and Test Method E1603) have been successfully used widely in various industries and applications to determine that a given package is or is not a “leaker.” The sensitivity of any selected leak test method has to be considered to determine its applicability to a specific situation.
The procedures presented in this test method allow the user to carry out package and seal integrity testing with sufficient sensitivity to quantify seals in the previously defined moderate to very fine seal ranges.
By employing seal-isolating leak testing fixtures, packages constructed of various materials can be tested in the full range of seal performance requirements. Design of these fixtures is beyond the scope of this method.
These seal/package integrity test procedures can be utilized as:
A design tool,
For tooling qualification,
Process setup,
Process validation tool,
Quality assurance monitoring, or
Research and development.
SCOPE
1.1 This test method includes several procedures that can be used for the measurement of overall package and seal barrier performance of a variety of package types and package forms, as well as seal/closure types. The basic elements of this method include:
General Information
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: F2391 − 05(Reapproved 2011)
Standard Test Method for
Measuring Package and Seal Integrity Using Helium as the
Tracer Gas
This standard is issued under the fixed designation F2391; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 1.3 The sensitivity of the method can range from the
detection of:
1.1 Thistestmethodincludesseveralproceduresthatcanbe
-2 3 -5 3 –1
1.3.1 Large leaks—10 Pa·m /s to 10 Pa·m /s (10
used for the measurement of overall package and seal barrier
-4
cc/sec/atm to 10 cc/sec/atm).
performance of a variety of package types and package forms,
-5 3 -7 3 -4
1.3.2 Moderate leaks—10 Pa·m /s to 10 Pa·m /s (10
aswellasseal/closuretypes.Thebasicelementsofthismethod
-6
cc/sec/atm to 10 cc/sec/atm).
include:
-7 3 -9 3 -6
1.3.3 Fineleaks—10 Pa·m /sto10 Pa·m /s(10 cc/sec/
1.1.1 Helium (employed as tracer gas),
-8
atm to 10 cc/sec/atm).
1.1.2 Helium leak detector (mass spectrometer), and
-9 3 -11 3 -8
1.3.4 Ultra-Fine leak—10 Pa·m /s to 10 Pa·m /s (10
1.1.3 Package/product-specific test fixtures.
-10
cc/sec/atm to 10 cc/sec/atm).
1.1.4 Most applications of helium leak detection are
destructive,inthatheliumneedstobeinjectedintothepackage
NOTE 1—Conversion from cc/sec/atm to Pa·m /s is achieved by
multiplying by 0.1.
afterthepackagehasbeensealed.Theinjectionsitethenneeds
to be sealed/patched externally, which often destroys its
1.4 The terms large, moderate, fine and ultra-fine are rela-
saleability.Alternatively,ifheliumcanbeincorporatedintothe
tive terms only and do not imply the acceptability of any leak
headspace before sealing, the method can be non-destructive
rate. The individual application dictates the level of integrity
because all that needs to be accomplished is to simply detect
needed. For many packaging applications, only “large leaks”
for helium escaping the sealed package.
are considered unacceptable and the ability to detect smaller
leaksisimmaterial.Allleakratesreferredtointhismethodare
1.2 Two procedures are described; however the supporting
based on conversion of actual conditions (based on partial
data in Section 14 only reflects Procedure B (Vacuum Mode).
pressureofhelium)tooneatmospherepressuredifferentialand
The alternative, Sniffer Mode, has proven to be a valuable
standard temperature conditions.
procedure for many applications, but may have more variabil-
ityduetoexactlythemannerthattheoperatorconductsthetest
1.5 Themethodmayhaveapplicabilitytoanypackagetype:
such as whether the package is squeezed, effect of multiple
1.5.1 Flexible,
small leaks compared to fewer large leaks, background helium
1.5.2 Semi-rigid, or
concentration, package permeability and speed at which the
1.5.3 Rigid.
scan is conducted. Further testing to quantify this procedure’s
variability is anticipated, but not included in this version.
1.6 The sensitivities reported in the supporting data for this
1.2.1 Procedure A: Sniffer Mode—the package is scanned method pertain to the detectability of helium emanating from
externally for helium escaping into the atmosphere or fixture. the sample and are not a function of the packaging form.
1.2.2 Procedure B: Vacuum Mode—the helium containing
1.7 The method is not applicable to breathable or porous
package is placed in a closed fixture.After drawing a vacuum,
packaging.
helium escaping into the closed fixture (capture volume) is
1.8 The results obtained can be qualitative, semi-
detected. Typically, the fixtures are custom made for the
quantitative or quantitative depending on the procedure used.
specific package under test.
1.9 Testfixturedesignisnotwithinthescopeofthismethod
excepttonotethatdifferentdesignswillbeneededfordifferent
applications (which have different package types and package
ThistestmethodisunderthejurisdictionofASTMCommitteeF02onFlexible
Barrier Packaging and is the direct responsibility of Subcommittee F02.40 on
integrity requirements). Furthermore, the fixture selection and
Package Integrity.
design will be based on where the testing is to be conducted
Current edition approved April 1, 2011. Published April 2011. Originally
within the manufacturing process (in other words, quality
approved in 2005. Last previous edition approved in 2005 as F2391 – 05. DOI:
10.1520/F2391-05R11. control versus research).
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F2391 − 05 (2011)
1.10 This standard does not purport to address all of the 3.2.3 fine leaks—For the purpose of this test method, leaks
-7 3
safety concerns, if any, associated with its use. It is the that exhibit gas/vapor leak rates between 1×10 Pa·m /s to
-9 3 -6 -8
responsibility of the user of this standard to establish appro- 10 Pa·m /s (1×10 cc/sec/atmosphere to 1×10 cc/sec/
priate safety and health practices and determine the applica- atmosphere).
bility of regulatory limitations prior to use.
3.2.4 flexible packaging—Packages (typically, pouches, sa-
chets, and bags) constructed of materials that are readily
2. Referenced Documents
bendable. (See also Terminology Method F17)
2.1 ASTM Standards:
3.2.5 impermeable packaging—Packages constructed of
D996Terminology of Packaging and Distribution Environ-
materials (typically metal or glass) that prevent gases/vapors
ments
from flowing into or out of the package.
D3078Test Method for Determination of Leaks in Flexible
3.2.6 large leaks—Forthepurposeofthistestmethod,leaks
Packaging by Bubble Emission
-2 3
that exhibit gas/vapor leak rates between 1×10 Pa·m /s to
D4991Test Method for Leakage Testing of Empty Rigid
-5 3 –1 -4
1×10 Pa·m /s (1×10 cc/sec/atm to 1×10 cc/sec/
Containers by Vacuum Method
atmosphere).
E432Guide for Selection of a Leak Testing Method
E479Guide for Preparation of a Leak Testing Specification 3.2.7 measured helium leak rate (MHLR)—Helium signal
E493Test Methods for Leaks Using the Mass Spectrometer
level obtained based on the actual helium concentration in the
Leak Detector in the Inside-Out Testing Mode package.
E498Test Methods for Leaks Using the Mass Spectrometer
3.2.8 moderate leaks—For the purpose of this test method,
-5 3
Leak Detector or Residual Gas Analyzer in the Tracer
leaks that exhibit gas/vapor leak rates between 1×10 Pa·m /s
Probe Mode -7 3 -4 -6
to 10 Pa·m /s (1×10 cc/sec/atmosphere to 1×10 cc/sec/
E499Test Methods for Leaks Using the Mass Spectrometer
atmosphere).
Leak Detector in the Detector Probe Mode
3.2.9 outgassing—The release of adsorbed, absorbed or
E691Practice for Conducting an Interlaboratory Study to
physically trapped gas from a surface of structure.
Determine the Precision of a Test Method
3.2.10 pass/fail criterion—The predeterminedAHLR above
E1603Test Methods for Leakage Measurement Using the
which the package being tested is considered defective and,
Mass Spectrometer Leak Detector or Residual Gas Ana-
therefore, unacceptable.
lyzer in the Hood Mode
F17Terminology Relating to Flexible Barrier Packaging
3.2.11 permeable packaging—Packages,inwholeorinpart,
F1327Terminology Relating to Barrier Materials for Medi-
that allow gases/vapors to flow into and out of a package via
cal Packaging (Withdrawn 2007)
diffusion controlled process.
2.2 Other Documents:
3.2.12 semi-rigid packaging—Packages (typically, thermo-
Principal author L. Kirsch, et al - (shown in reference
formable, or cold-formable materials) that are formed into
Appendix X1 as literature references 1, 2, 3 and 5)
blisters or trays, with associated lidding materials applied as
Principalauthor L. Nguyen, et al - (shown in reference
the closure means.
appendix I at literature reference 4)
3.2.13 ultra fine leaks—For the purpose of this test method,
Co-authorsinclude C. Moeckly, L. Nguyen, R. Gerth, W.
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leaks that exhibit gas/vapor leak rates between 1×10 Pa·m /s
Muangsiri, R. Scheire, D. M. Guazzo, L. Kirsch, G.
-11 3 -8 -10
to 1×10 Pa·m /s (1×10 cc/sec/atmosphere to 1×10
Schmitt,A.Kirsch,M.Koch,T.Wertli,M.LehmanandG.
cc/sec/atmosphere).
Schramm.
3.2.14 virtual leak—Asource of detectable tracer gas other
3. Terminology
than from a defect of the seal or package. Such a virtual leak
3.1 General Term Definitions—For definitions used in this may be the result of membrane permeability, surface desorp-
standard see Terminology D996, Terminology F17 and Termi- tion or release of trapped gas.
nology F1327.
4. Summary of Test Procedures
3.2 Specific Term Definitions:
3.2.1 actual helium leak rate (AHLR)—Measured helium 4.1 Therearetwobasictestprocedurescontainedinthistest
leak rate (MHLR) signal level adjusted to a driving force of
method:
100% concentration at 101 KPa (1.0 atmosphere), absolute. 4.1.1 Procedure A—Sniffer Mode.
4.1.2 Procedure B—Vacuum Mode.
3.2.2 breathable/porous packaging—Packages, in whole or
inpart,thatintentionallyallowgases/vaporstoflowfreelyinto
4.2 Both of these test procedures require the package under
and out of the package. (See also Terminology F1327)
test to have helium at some measurable level on the side of the
package opposite the leak detector sensor (typically, the inside
of the package). If the package cannot, or should not be sealed
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
with helium inside, the test fixture used for that particular test
Standards volume information, refer to the standard’s Document Summary page on
needs to provide a means of helium introduction at the
the ASTM website.
appropriate location and the appropriate time in the test cycle.
The last approved version of this historical standard is referenced on
www.astm.org. The one exception is a package with a gross leak for which a
F2391 − 05 (2011)
variation of the helium pressurized “back-filling” or “soaking” eliminate background helium with ventilation, location of
technique may be applicable. In all cases helium, at as high a supply cylinders, proper sample isolation fixturing or other
concentrationaspracticable,mustbepresentononesideofthe means.
package/seal barrier element.
6.3 When attempting to detect very small leaks, care must
be taken to eliminate, minimize, or compensate for false
4.3 To quantify the leak rate level of a given package, or
package seal, the partial pressure driving force of the helium readings from “virtual leak” sources, particularly trapped
helium in seal areas.
must be known. Therefore, an important part of the process of
conducting a leak rate test is the determination of the concen-
6.4 The permeation of the package by helium does not
trationofheliumatoneatmosphere(absolutepressure)present
indicate a leak. Care must be taken to understand the level of
during the test. Generally speaking, some type of calibrated
permeation to prevent misinterpretation of results. Similarly,
residualgasanalyzer(RGA)devicewillneedtobeutilizedfor
somematerialsmayabsorbheliumandyieldfalseresultswhen
this step.
tested. Outgassing of these materials may greatly increase test
time.
4.4 The MHLR (measured helium leak rate) values will be
determinedbasedonacomparisontothecalibration,reference
6.5 These procedures, particularly when detecting moderate
standard employed. It is subsequently adjusted to an AHLR
to very fine leaks, should be carried out using calibrated
(actual helium leak rate), which is based on the actual package
external leak standards.
helium partial pressure (see 4.5).
6.6 Physical/mechanical constraints are generally required
4.5 If appropriate, the AHLR value for the package under
for flexible and semi-rigid packages to avoid vacuum-induced
test can be compared to the pre-established Pass/Fail criterion
seal failures. Properly constrained packages can mean the
forthatspecificproduct/packagetoascertainacceptability(per
difference between success and failure in carrying out the test
established specification requirements).
procedure.
7. Apparatus
5. Significance and Use
7.1 Ahelium leak detector (mass spectrometer).An oil-free
5.1 The vacuum, bubble test method, as described in Test
vacuum system is recommended with hard vacuum test port
Method D3078, and various other leak detection methods
and sniffer probe attachment (as appropriate for a specific
described elsewhere (Test Method D4991, Guide E432, Guide
application)forthoseapplicationswherethetestingareaneeds
E479, Test Method E493, Test Method E498, Test Method
to be maintained as a clean environment, or where the release
E499, and Test Method E1603) have been successfully used
of vacuum pump oil could lead to product contamination, or
widely in various industries and applications to determine that
both.
a given package is or is not a “leaker.” The sensitivity of any
7.2 External calibrated leaks (calibrated within the last 12
selected leak test method has to be considered to determine its
applicability to a specific situation. months; 6 months is recommended). At least three ranges
should be covered depending on the application; typically
5.2 The procedures presented in this test method allow the -6
-7 -8
1×10 , 1×10 and 1×10 cc/s/atm. Alternatively, more cali-
user to carry out package and seal integrity testing with
brated leaks may be used.
sufficient sensitivity to quantify seals in the previously defined
7.3 Avacuumchamber,withcustom-designconstraintsthat
moderate to very fine seal ranges.
are package-specific (sniffer mode testing may not require a
5.3 By employing seal-isolating leak testing fixtures, pack-
vacuum chamber).
ages constructed of various materials can be tested in the full
7.4 A headspace analyzer device for measuring the partial
range of seal performance requirements. Design of these
pressure of (concentration at 1 atm pressure) helium in
fixtures is beyond the scope of this method.
samples.
5.4 These seal/package integrity test procedures can be
7.5 The method to introduce helium into the package needs
utilized as:
to be developed specifically for the package under test.
5.4.1 A design tool,
Techniques and devices that have been successfully employed
5.4.2 For tooling qualification,
include:
5.4.3 Process setup,
7.5.1 Pre-filling of packages using an on-line flooding
5.4.4 Process validation tool,
fixture (helium introduced to package headspace prior to
5.4.5 Quality assurance monitoring, or
sealing).
5.4.6 Research and development.
7.5.2 Post-fillingofpackagesbyinjectionofheliumintothe
sealedpackage.Afinegagesyringeneedleandflow-controlled
6. Interferences
heliumgassupply,followedbysealingofthepuncturesitehas
6.1 The introduction of the helium tracer gas to the
...
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