ASTM F2095-07(2013)

Standard Test Methods for Pressure Decay Leak Test for Flexible Packages With and Without Restraining Plates

SIGNIFICANCE AND USE
5.1 These test methods provide a rapid, simple to apply method to detect small leaks in flexible package seals or walls at the leak rate level of greater than 1 × 10−4 sccs, thus providing a measure of package integrity. Porous barrier film packages made non-porous with an impermeable film forming coating may demonstrate lateral leakage through the barrier material. Verification of leakage differences from background leakage must be included in validation methods. The use of calibrated hole sizes or orifices may be appropriate to determine leakage sensitivity or barrier integrity for these materials.  
5.2 While theoretical leak rate sensitivity can be established by calculation, the test measurement is in pressure units and the measuring instrument must be calibrated, certified, and verified with these units.  
5.3 The pressure decay method of leak testing is a physical measure of package integrity. When testing medical packaging which must conform to ISO 11607–1: 2006 standards, it may necessary to verify the results of the pressure decay test method with other sterile package integrity test methods.  
5.4 Test Method A allows packages to be pressurized without restraint. In Test Method A the pouch, tray, or other type package will contain a volume of air defined by its mechanical configuration and its ability to resist internal pressure applied. This test method requires that the package reach a stable volume configuration (stop stretching) to make a measurement.  
5.5 Test Method B allows the use of rigid restraining plates against the walls of the package to limit its volume and stabilize the package volume.
SCOPE
1.1 These test methods cover the measurement of leaks in nonporous film, foil, or laminate flexible pouches and foil-sealed trays, which may be empty or enclose solid product. If product is enclosed, seals or surfaces cannot be in contact with water, oils, or other liquid.  
1.2 These test methods will detect leaks at a rate of 1 × 10−4 sccs (standard cubic centimetres per second) or greater, in flexible packages. The limitation of leak rate is dependent on package volume as tested.  
1.3 The following test methods are included:  
1.3.1 Test Method A—Pressure Decay Leak Test for Flexible Packages Without Restraining Plates  
1.3.2 Test Method B—Pressure Decay Leak Test for Flexible Packages With Restraining Plates  
1.4 These test methods are destructive in that they require entry into the package to supply an internal pressure of gas, typically air or nitrogen, although other gases may be used. The entry connection into the flexible package must be leak-tight.  
1.5 For porous packages, see 9.3.  
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Jul-2013
• ICS: 19.060 - Mechanical testing
• ICS: 55.040 - Packaging materials and accessories
• Technical Committee: F02 - Primary Barrier Packaging
• Drafting Committee: F02.40 - Package Integrity

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: F2095 − 07 (Reapproved 2013)
Standard Test Methods for
Pressure Decay Leak Test for Flexible Packages With and
Without Restraining Plates
This standard is issued under the fixed designation F2095; 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 ASTM Test Methods
E691Practice for Conducting an Interlaboratory Study to
1.1 These test methods cover the measurement of leaks in
Determine the Precision of a Test Method
nonporous film, foil, or laminate flexible pouches and foil-
F17Terminology Relating to Flexible Barrier Packaging
sealed trays, which may be empty or enclose solid product. If
2.2 Other Document:
product is enclosed, seals or surfaces cannot be in contact with
ANSI/AAMI/ISO11607–1:2006Packaging for Terminally
water, oils, or other liquid.
Sterilized Medical Devices—Part 1: Requirements for
−4
1.2 Thesetestmethodswilldetectleaksatarateof1×10
Materials, Sterile Barrier Systems, and Packaging Sys-
sccs (standard cubic centimetres per second) or greater, in
tems
flexible packages. The limitation of leak rate is dependent on
package volume as tested.
3. Terminology
1.3 The following test methods are included:
3.1 Definitions of Terms Specific to This Standard:
1.3.1 Test Method A—PressureDecayLeakTestforFlexible
3.1.1 integrity—the unimpaired physical condition of the
Packages Without Restraining Plates
package. This implies that there are no leaks in the seals or
1.3.2 Test Method B—PressureDecayLeakTestforFlexible
body materials.
Packages With Restraining Plates
3.1.2 leak—See Terminology F17.
1.4 These test methods are destructive in that they require
3.1.3 nonporous—types of materials that are not purposely
entry into the package to supply an internal pressure of gas,
designed to transfer gases through their matrix.
typicallyairornitrogen,althoughothergasesmaybeused.The
3.1.4 restraining plates—plates of rigid material, for
entry connection into the flexible package must be leak-tight.
example, aluminum, that are used to restrict the movement of
1.5 For porous packages, see 9.3.
the package during inflation.
1.6 This standard does not purport to address all of the
3.1.5 seal—See Terminology F17.
safety concerns, if any, associated with its use. It is the
3.1.6 standard cubic centimetre per second (sccs)—theflow
responsibility of the user of this standard to establish appro-
rate of a gas (air) at standard conditions of 20°C (68°F) and
priate safety and health practices and determine the applica-
101.3 kPa (14.7 psig) (1 atmosphere or 760 mm Hg).
bility of regulatory limitations prior to use.
3.1.6.1 Discussion—Conditions may be varied depending
2. Referenced Documents on the source of data.Always check the definition being used.
2.1 ASTM Standards:
4. Summary of Test Method
D4332Practice for Conditioning Containers, Packages, or
4.1 Detection of leak paths in flexible packages that have
Packaging Components for Testing
nonporous material surfaces and seals can be accomplished by
E177Practice for Use of the Terms Precision and Bias in
pressurization of the package to a fixed pressure, shutting off
the pressure and connecting a pressure transducer. Observed
These test methods are under the jurisdiction of ASTM Committee F02 on
changes in pressure indicate the presence of leakage paths in
FlexibleBarrierPackagingandarethedirectresponsibilityofSubcommitteeF02.40
the package seals or pinholes in the surfaces.This leak may be
on Package Integrity.
represented in decay pressure units or calculated leak rate
Current edition approved Aug. 1, 2013. Published September 2013. Originally
approved in 2001. Last previous edition approved in 2007 as F2095–07. DOI:
units. To accomplish this technique, a leak-tight measuring
10.1520/F2095-07R13.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
the ASTM website. 4th Floor, New York, NY 10036, http://www.ansi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F2095 − 07 (2013)
path must be available between the package interior volume pressure applied. This test method requires that the package
and the pressure transducer (see Fig. 1). reachastablevolumeconfiguration(stopstretching)tomakea
measurement.
NOTE 1—The coating used on porous barrier films will mask defects
(pin-holes) in/through the porous material but not defects in the seals.
5.5 Test Method B allows the use of rigid restraining plates
against the walls of the package to limit its volume and
4.2 Restraining plates may be used to limit the volume of
stabilize the package volume.
the pressurized package. Because the sensitivity of these test
methods is dependent in part on the internal volume of the
6. Apparatus
package, the effect of restraining plate use is to increase the
sensitivityofthetest(seeFig.2).SeeAppendixX1forfurther
6.1 Test Method A:
discussion of the effects of restraining plates on these test
6.1.1 A measuring instrument that provides the following:
methods.
6.1.1.1 A means to detect pressure changes with sufficient
sensitivity to achieve theoretical leak rates in the package
5. Significance and Use
specification;
5.1 These test methods provide a rapid, simple to apply
6.1.1.2 Automatic timer controls to pressurize the package
method to detect small leaks in flexible package seals or walls
to a preset pressure, hold the pressure for a set time, and
−4
at the leak rate level of greater than1×10 sccs, thus
provide a time period during which pressure change data can
providing a measure of package integrity. Porous barrier film
be taken;
packages made non-porous with an impermeable film forming
6.1.1.3 A means to set pressure;
coating may demonstrate lateral leakage through the barrier
6.1.1.4 A means of holding and displaying the pressure
material. Verification of leakage differences from background
change inside the package at the end of the test cycle;
leakage must be included in validation methods. The use of
6.1.1.5 Ameans (optional) to set pressure decay limits for a
calibrated hole sizes or orifices may be appropriate to deter-
test method and alert the operator if the limit is exceeded.
mineleakagesensitivityorbarrierintegrityforthesematerials.
6.1.2 Ameanstoenterthepackageinaleaktightmannerso
that an inflation pressure can be applied to the package and
5.2 Whiletheoreticalleakratesensitivitycanbeestablished
changes in internal pressure can be sensed.
bycalculation,thetestmeasurementisinpressureunitsandthe
measuringinstrumentmustbecalibrated,certified,andverified
NOTE 2—It is important to verify the leak integrity of the entry means
with these units.
sothatitdoesnotcontributetothepressurechangessensedduringtesting.
5.3 The pressure decay method of leak testing is a physical
6.2 Test Method B—Using Restraining Plates:
measure of package integrity.When testing medical packaging 6.2.1 The measuring instrument shall have the characteris-
which must conform to ISO 11607–1: 2006 standards, it may
tics described in 6.1.1.1-6.1.1.5.
necessarytoverifytheresultsofthepressuredecaytestmethod 6.2.2 Parallel, rigid plates are required. An ability to adjust
with other sterile package integrity test methods.
plate separation is desirable. The surface of the plates should
providelimitedporosityinordertopreventblockingofpinhole
5.4 Test Method A allows packages to be pressurized
leaks in the walls (see Fig. 2).
without restraint. In Test Method A the pouch, tray, or other
type package will contain a volume of air defined by its
NOTE 3—Several techniques have been used to provide a means to
mechanical configuration and its ability to resist internal prevent blocking or lowering of the leak rate in package material walls in
FIG. 1 Leak-Tight Entry System
F2095 − 07 (2013)
FIG. 2 Restraining Fixture with Leak-Tight Entry System
contact with the plates. These techniques include the use of semi-porous
9.1.1 Package Preparation—The package may be tested
plastic, scoring of plate surfaces and use of screen-type materials.
with or without the product enclosed. To maximize sensitivity
6.2.3 Ameanstoenterthepackageinaleak-tightmannerso of the test, the smallest internal volume of the package is
that an inflation pressure can be applied to the package and desired.
changes in internal pressure can be sensed.
9.1.2 Instrument Preparation (see Annex A1 for informa-
tion on determining appropriate test parameters):
NOTE 4—It is important to verify the leak integrity of the entry means
9.1.2.1 Select and set the test pressure.
sothatitdoesnotcontributetothepressurechangessensedduringtesting.
9.1.2.2 Select and set the timers for charge (pressurization),
7. Sampling
settle (stabilization), and test (data taking period).
9.1.2.3 Select and set pressure decay limits (if available).
7.1 The sample size is chosen to permit an adequate
9.1.3 Attach the inflation probe (supply and sensor) to the
determination of representative performance.
instrument.
7.2 Sample identification should be made prior to testing to
9.1.4 Attach the leak-tight entry device and inflation probe
allowtheoperatortorefertospecifictestsamples,ifnecessary.
sensor to the package (see Fig. 1).
Record information such that test results and anomalies are
9.1.5 Begin the test by activating the timer controls and
identifiable back to the individual specimens.
valves to inflate, hold, and measure the test pressure inside the
package.
8. Conditioning
9.1.6 Observe the pressure decay at the end of the test time
8.1 Package samples should be conditioned to obtain the
period, and note if the pressure decay limit has been exceeded.
same temperature conditions as exist for the test apparatus.
Since measured pressure change is also a function of
NOTE 6—Choice of times depends on package variables and leak rate
requirements. For example, small changes in initial test pressure may
temperature, then the samples must be at a stable temperature.
occur from flexible package stretch, thus slightly increasing its volume
Most testing will occur at standard laboratory conditions of 23
(decreasing its pressure) or from fixture contact or the expanding gas
6 2°C (73 6 4°F) and 50 6 5% relative humidity. Other
medium. Increased stabilization time will allow these effects to become
conditions should be recorded at the time of the test.
stable before the test data period begins. Test times are selected based on
required leakage rates or pressure decay criteria along with the package
NOTE 5—As seen in the combined gas laws, the pressure change is a
volume. See Annex A1 for further discussion.
functionoftemperature.Testpackagesandthetestmedium(air)shouldbe
at similar temperatures.
9.2 Test Method B—With Restraining Plates:
9.2.1 Package Preparation—The package may be tested
9. Procedure
with or without the product enclosed. To maximize sensitivity
9.1 Test Method A—No Restraining Plates: of the test, the smallest internal volume of the package is
F2095 − 07 (2013)
desired. To achieve the minimum volume, the smallest gap 11. Precision and Bias
between restraining plates is advisable.
11.1 This interlaboratory study was conducted to evaluate
9.2.2 Instrument Preparation (see Annex A1 for informa-
the precision of the pressure decay test method of leak
tion on determining appropriate test parameters):
detection in identifying a known leak in various sealed,
9.2.2.1 Select and set the test pressure.
nonporous empty packages. Two variations of the test method
9.2.2.2 Select and set the timers for charge (pressurization),
were examined, with Test Method A allowing the pressurized
settle (stabilization), and test (data taking period).
packages to expand without restraint, and Test Method B
9.2.2.3 Select and set pressure decay limits (if available).
utilizing rigid restraining plates to limit package expansion
9.2.3 Attach the inflation probe (supply and sensor) to the
under pressurization. Each of five laboratories tested ten
instrument.
randomly drawn test specimens from each of three materials
9.2.4 Attach the leak-tight entry device and inflation probe
under each of the two test methods, A and B. Materials were
sensor to the package (Fig. 1).
chosen to represent a range of products for which the test
9.2.5 Enclose the package and probe in the restraining
methodsaresuitable.Thedesignoftheexperimentwassimilar
fixture.
to that of Practice E691.
9.2.6 Begin the test by activating the timer controls and
11.2 The precision information given as follows represents
valves to inflate, hold, and measure the test pressure inside the
pressure decay as measured in psig. The terms “repeatability
package.
limit” and “reproducibility limit” are used in accordance with
9.2.7 Observe the pressure decay at the end of the test time
Practice E177.
period and note if the pressure decay limit has been exceeded.
Test Method A—No Restraining Plates
NOTE 7—Choice of times depends on package variables and leak rate
95 % Repeatability 95 % Reproducibility
requirements. For example, small changes in initial test pressure may
Pressure Decay Limit (Within Limit (Between
occur from flexible package stretch, thus slightly increasing its volume Material Average, psig Laboratory) Laboratories)
−4 −4 −4
Foil pouch 246.020 × 10 99.655 × 10 191.932 × 10
(decreasing its pressure) or from fixture contact or the expanding gas
−4 −4 −4
Film pouch 217.200 × 10 54.370 × 10 67.169 × 10
medium. Increased stabilization time will allow these effects to become
−4 −4 −4
Foil tray 48.240 × 10 21.723 × 10 27.482 × 10
stable before the test data period begins. Test times are selected based on
required leak rates or pressure decay criteria along with the package Test Method B—With Restraining Plates
95 % Repeatability 95 % Reproducibility
volume. See Annex A1 for further discussion.
Pressure Decay Limit (Within Limit (Between
9.3 For porous packages, it is necessary to coat the porous
Material Average, psig Laboratory) Laboratories)
−4 −4 −4
Foil pouch 149.560 × 10 32.283 × 10 32.283 × 10
materialwithacoatingthattransformstheporousmaterialinto
−4 −4 −4
Film pouch 195.540 × 10 13.748 × 10 14.918 × 10
a non-porous material, as defined in ANSI/AAMI/
−4 −4 −4
Foil tray 64.900 × 10 19.629 × 10 26.095 × 10
ISO11607-1,AnnexC.Doingthiswillallowtheevaluationof
...