ASTM F1980-21

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it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: F1980 − 16 F1980 − 21
Standard Guide for
Accelerated Aging of Sterile Barrier Systems forand Medical
Devices
This standard is issued under the fixed designation F1980; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This guide provides information for developing accelerated aging protocols to rapidly determine the effects, if any, due to
model the possible effects of the passage of time on the sterile integrity of the sterile barrier system (SBS), as defined in
ANSI/AAMI/ISO 11607–1:2006 11607–1: 2019 and the physical properties of their component packaging materials. Guidance for
developing accelerated aging protocols may also be used for medical devices and medical device materials.
1.2 Information obtained using this guide may be used to support regarded as sufficient evidence for expiration date claims for
medical device sterile barrier systems.devices and sterile barrier systems until data from real-time aging studies are available.
1.3 The accelerated aging guideline addresses the sterile barrier systems in as a whole with or without devices. The sterile barrier
system material and device interaction compatibility that may be required for new product development or the resulting evaluation
is not addressed in this guide.
1.4 Real-time aging protocols are not addressed in this guide; however, it is essential that real-time aging studies be performed
to confirm the accelerated aging test results using the same methods of evaluation. Real-time aging (stability) is the requirement
of ANSI/AAMI/ISO 11607–1: 2019.
1.5 Methods used for sterile barrier system validation, which include the machine process, the effects of the sterilization process,
environmental challenge, distribution, handling, and shipping events, are performance validation, which include, environmental
challenge, distribution, handling, and shipping events, are used for package performance (event-related loss of integrity) testing
and are beyond the scope of this guide.
1.6 This guide does not address environmental challenging that stimulatessimulates extreme climactic conditions that may exist
in the shipping and handling environment. Refer to Practice D4332 for standard conditions that may be used to challenge the sterile
barrier system to realistic extremes in temperature and humidity conditions. See Terminology F1327F17 for a definition of
“environmental challenging.”
1.7 The data obtained from accelerated aging studies is not to be used as a manner of establishing label storage conditions for
sterile barrier systems.
1.8 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
This guide is under the jurisdiction of ASTM Committee F02 on Primary Barrier Packaging and is the direct responsibility of Subcommittee F02.50 on Package Design
and Development.
Current edition approved Sept. 15, 2016Dec. 15, 2021. Published September 2016December 2021. Originally approved in 1999. Last previous edition approved in
20112016 as F1980 – 07F1980 – 16.(2011). DOI: 10.1520/F1980-16.10.1520/F1980-21.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F1980 − 21
1.9 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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.10 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
D4332 Practice for Conditioning Containers, Packages, or Packaging Components for Testing
E337 Test Method for Measuring Humidity with a Psychrometer (the Measurement of Wet- and Dry-Bulb Temperatures)
F17 Terminology Relating to Primary Barrier Packaging
F1327 Terminology Relating to Barrier Materials for Medical Packaging (Withdrawn 2007)
F2097 Guide for Design and Evaluation of Primary Flexible Packaging for Medical Products
2.2 AAMIOther Standards:
ANSI/AAMI/ISO 11607–1: 2006,2019 Packaging for Terminally Sterilized Medical Devices
ASHRAE 170-2017 Ventilation of Health Care Facilities
AAMI TIR 22–2007,ISO TS 16775:2014 Guidance for ANSI/AAMI/ISO 11607, Packaging for Terminally Sterilized Medical
DevicesPackaging for terminally sterilized medical devices — Guidance on the application of ISO 11607-1 and ISO 11607-2
3. Terminology
3.1 Definitions—For general definitions of packaging for medical devices, see ANSI/AAMI/ISO 11607. 11607–1: 2019. For
terminology related to barrier materials for medical packaging see Terminology F17.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 accelerated aging (AA), n—storage of samples at an elevated temperature (T ) in order to simulate real time aging in a
AA
reduced amount of time.
3.2.2 accelerated aging factor (AAF), n—an estimated or calculated ratio of the time to achieve the same level of physical property
change as a sterile barrier system stored at real time (RT) conditions.
3.2.3 accelerated aging temperature (T ), n—the elevated temperature at which the aging study is conducted, and it may be based
AA
on the estimated storage temperature, estimated usage temperature, or both.
3.2.4 accelerated aging time (AAT), n—the length of time the accelerated aging is conducted.
3.2.5 ambient temperature (T ) , ), n—storage temperature for real-time aging (RT) samples that represents storage conditions.
RT
is typical for storage conditions. Also, the temperature used to calculate the accelerated aging duration.
3.2.6 sterile barrier system shelf life, n—the amount of real time that a sterile barrier system can be expected to remain in storage
at ambient conditions, or under specified conditions of storage, and maintain its critical performance properties.
3.2.7 real-time aging (RT), n—storage time of samples at ambient conditions.
3.2.8 real-time equivalent (RTE), n—amount of real-time aging to which given accelerated aging conditions are estimated to be
equivalent.
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 Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
Available from American Society of Heating, Refrigerating, and Air-Conditioning Engineers, Inc. (ASHRAE), 1791 Tullie Circle, NE, Atlanta, GA 30329,
http://www.ashrae.org.
Available from International Organization for Standardization (ISO), ISO Central Secretariat, Chemin de Blandonnet 8, CP 401, 1214 Vernier, Geneva, Switzerland,
https://www.iso.org.
F1980 − 21
3.2.9 zero time (t ), n—the beginning of an aging study.
3.3 Symbols:
Q = an aging factor for 10°C increase or decrease in temperature.
T = temperature at which a material melts.
m
T = glass transition temperature.
g
T = alpha temperature; heat distortion temperature.
α
4. Significance and Use
4.1 The loss of sterile barrier system integrity may occur as a result of physical properties of the materials and adhesive or cohesive
bonds degrading over time andor by subsequent dynamic events during shipping and handling.handling, or both. Accelerated and
real time aging verifies the time-related aspects of potential integrity loss only.
4.2 ISO 11607–1:2006, clause 6, ANSI/AAMI/ISO 11607–1: 2019, sub-clause 6.1.3, states that “the packaging system shall
provide physical protection and in order to maintain integrity of the sterile barrier system. The system.” Sub-clause 6.1.6 states
that, “A terminally sterilized sterile barrier system shall maintain sterility to the with its protective packaging, if included, shall
be designed to, maintain sterility through exposure to expected conditions and hazards during the specified processing, storage,
handling, and distribution until that SBS is opened at the point of use or until the expiry date. Stability date.” Sub-clause 8.3.1
states, “Stability testing shall demonstrate that the sterile barrier system maintains integrity over time. Stability testing time.”
Sub-clause 8.3.3 states, “Stability testing, using accelerated aging protocols, shall be regarded as sufficient evidence for claimed
expiry datedates until data from real time real-time aging studies are available.”
4.3 Real time aging programs provide the best data to ensure that sterile barrier system system/medical device materials and sterile
barrier system system/medical device integrity do not degrade over time. However, due to market conditions in which products
may become obsolete in a short time, and the needdesire to get new products to market in the shortest possible time, real time aging
studies do not meet this objective. Accelerated aging studies can provide an alternative means. means of screening for possible
aging-related failure mechanisms in the SBS or medical device. To ensure that accelerated aging studies do truly represent real time
effects, real time aging studies must be conducted in parallel to accelerated studies. Real time studies must be carried out to the
claimed shelf life of the product and be performed to their completion.
4.4 Conservative accelerated aging factors (AAFs) must be used if little is known about the sterile barrier system material being
evaluated. More aggressive AAFs may be used with documented evidence to show a correlation between real time and accelerated
aging.
4.5 When conducting accelerated aging programs for establishing expiry dating claims, it must be recognized that the data
obtained from the study is based on conditions that simulate the effects of aging on the materials. The resulting creation of an
expiration date or shelf life is based on the use of a conservative estimate of the aging factor (for example,(that is, Q ) and is
tentative until the results of real time aging studies are completed on the sterile barrier system.
NOTE 1—Determining AAFs are beyond the scope of this guide.
5. Apparatus
5.1 Room (or Cabinet) of such size that samples may be individually exposed to circulating air at the temperature and relative
humidity chosen. See 7.4.1 for sample configuration guidance.
5.1.1 Control Apparatus, capable of maintaining the room at the required atmospheric conditions within the tolerance limits.
5.2 Hygrometer—The instrument used to indicate the relative humidity should be accurate to 62 % relative humidity. A
psychrometer may be used either for direct measurement of relative humidity or for checking the hygrometer (see Test Method
E337).
Thor, P., “Humidity as Use Condition for Accelerated Aging of Polymers” MDDI Online, 2021.
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5.3 Thermometer—Any temperature-measuring device may be used provided it can accurately indicate the temperature to within
0.1°C or 0.2°F and be properly recorded. The dry-bulb thermometer of the psychrometer may be used either for direct measurement
or for checking the temperature-indicating device.
6. Accelerated Aging Theory
6.1 Accelerated aging Aging of materials refers to the accelerated study of variation of their properties over time, the generally
due to various degradation mechanisms (for example, thermo-oxidative or hydrolytic) inherent in the materials. For the purposes
of this guide, the properties of interest beingare those related to the safety and function of the material or sterile barrier system.
6.2 In an accelerated aging study, the material or sterile barrier system is subjected to an external stress, which is more severe,
or more frequently applied than the normal environmental stress, for a relatively short period of time.conditions which accelerate
the reaction kinetics of possible degradation pathways.
6.3 Accelerated aging techniques are based on the assumption empirical guidance that the chemical reactions (including those
involved in the deterioration of materialsmaterials) follow the Arrhenius reaction rate function. function, and assume little or no
change in reactant concentration(s). This function states that that, in general, a 10°C increase or decrease in temperature of a
homogeneous process results in, approximately, a two times or in a two-fold increase ⁄2-time change in the rate of a chemical
reaction (Q )). .
6.4 Determining the Q involves testing materials at various temperatures and defining the differences in reaction rate for a
10 10
10°10°C change in temperature. Modeling the kinetics of material deterioration is complex and difficult and is beyond the scope
of this guide.
6.5 A humidity factor to calculate the accelerated aging time (AAT) is not applicable for accelerated aging protocols. Unrealistic
or extreme temperature and humidity conditions may be of interest in overall sterile barrier system performance. However, this
must be evaluated in a separate study and is not related to aging of the materials. Since sterile barrier systems and medical device
are stored in environments that comprise varying levels of ambient humidity, and since the properties of some materials may
depend on the level of absorbed moisture (for example, polyamides absorb moisture from the environment and may have
degradation pathways involving moisture, while polyolefins do not), it is important to consider not only the accelerated aging
temperature conditions but also the ambient relative humidly during that accelerated aging. See Appendix X3 for more details on
the use of humidity in accelerated aging protocols.
NOTE 2—Degradation mechanisms for most flexible packaging materials used as sterile barrier systems do not involve moisture. However, materials used
in medical devices are far more varied, and hydrolytic degradation may be a factor in some of those materials. Knowledge of the materials used in either
the SBS or the device, and their relevant degradation mechanisms, is important in the proper design of an accelerated aging protocol.
6.6 It is important to consider that humidity will be part of the long-term storage use condition. Controlling humidity during
accelerated aging is intended to compensate for low relative humidity at intentionally elevated temperatures, necessary to
accelerate the effect of time. The goal of controlling humidity during accelerated aging is to avoid drying out materials (primarily
polymers) to moisture levels lower than typical in the long-term storage use condition. Dry accelerated aging conditions may cause
the user of this practice to miss moisture driven degradation that can occur on the shelf in long-term storage. Appropriate control
of relative humidity during accelerated aging ensures that potential moisture driven degradation mechanisms will be caught during
accelerated aging for moisture sensitive materials. The same relative humidity considerations are not necessary when the
temperature is not artificially elevated (for example, real-time aging). Control of relative humidity outside the scope of this
standard is left to the discretion of the user.
7. Accelerated Aging Plan
7.1 Characterization of Materials—AA theory and its application are directly related to packaging material composition. Material
Examples of material properties that may affect the results of accelerated aging studies may include:
Hemmerich, K. J., “General Aging Theory and Simplified Protocol for Accelerated Aging of Medical Devices,” Medical Plastics and Biomaterials, July/August 1998,
pp. 16–23.
Nelson, W., “Accelerated Testing Statistical Models, Test Plans, and Data Analyses,” John Wiley and Sons, New York, 1999.Nelson, W., Accelerated Testing Statistical
Models, Test Plans, and Data Analyses, John Wiley and Sons, New York, 1999.
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7.1.1 Composition,Composition (including laminating adhesives, primers, and coatings),
7.1.2 Morphology (glassy, amorphous, semi-crystalline, highly crystalline, % crystallinity, and so forth),
7.1.3 Thermal transitions (T , T , T ), as defined in 3.3,
m g α
7.1.4 Additives, processing agents, catalysts, lubricants, residual solvents, corrosive gases, and fillers.fillers,
7.1.5 Moisture absorption characteristics, and
7.1.6 Known degradation mechanisms (for example, hydrolysis, metal ion oxidation (MIO), photo-degradation, environmental
stress cracking (ESC), corrosion, oxidation). This can be accomplished by reviewing published literature/research.
7.2 Accelerated Aging Plan-Design Guidelines:
7.2.1 Temperature boundaries, based on the characterization of the device and sterile barrier system materials, must be considered
in order to ensure that initial, conservative aging factors are applied appropriately. The temperatures used should be based on the
characterization of the packaging materials and the intended storage conditions. Material characterization and composition are
factors in establishing the accelerated aging temperature boundaries. Temperature selection should be limited to prevent any
physical transition of material.
7.2.2 Room or Ambient Temperature (T )—Select a temperature that represents the actual product storage and use conditions.
RT
Selecting a higher temperature for will yield a longer, more conservative accelerated aging duration and can be useful for
TRT
creating accelerated aging data that verifies compatibility with a range of storage temperature conditions. For products labeled with
a specific long-term storage temperature range, aligning the used for the calculation of the AA duration with the upper limit
TRT
of the range is recommended.
NOTE 3—This temperature is typically between 20 to 25°C. A temperature of 25°C is considered a conservative approach.
7.2.3 Accelerated Aging Temperature (T )—Considering the characterization of the materials under investigation, select a
AA
temperature for the accelerated aging testing. The higher the accelerated aging temperature, the greater the AAF and, thus, the
shorter the accelerated aging time. Care must be taken not to elevate aging temperatures solely for the shortest possible accelerated
aging time. Excessively high temperatures may are likely to have an effect on the material that may never occur during real time
or at room temperature (see Appendix X1). Guidelines for selecting an aging temperature are as follows:
7.2.3.1 T should be below any material transitions (excluding those that occur below ambient conditions) or below where the
AA
sterile barrier system distorts. Consider the thermal transitions of the materials under investigation. (For more information on this
topic, see AAMI TIR 22–2007.)ISO TS 16775:2014.)
7.2.3.2 Keep T at or below 60°C (for example 50°C) unless a higher temperature has been demonstrated to be appropriate.
AA
Temperatures higher than 60°C are not recommended due to the higher probability in many polymeric systems to experience
nonlinear changes, such as percent crystallinity, formation of free radicals, and peroxide degradation. (For more information on
this topic, see AAMI TIR 22–2007.)ISO TS 16775:2014.)
NOTE 4—If sterile barrier systems containing liquid or other volatile components are tested, lower temperatures may beare generally required for safety
reasons.
NOTE 5—Tolerances of 62°C for the test temperature and 65 % for the humidity are acceptable. Since the shelf life of the finished sterile barrier system
is based on a conservative aging factor (Q ) of 2.0 for the accelerated aging protocol, any long term deviation in the temperature less than the specified
temperature in the protocol can be compensated for by increasing the total test duration time without invalidating the intent of the aging protocol.
NOTE 6—Where excursions in the test temperature occur over a long period of time, an assessment on the temperature effects to the packaging materials
and/oror the test duration adjustments required to achieve the desired estimate of shelf life life, or both, must be determined.
7.2.3.3 When elevated temperature aging is not feasible due to material characteristics, then real-time aging is the only option.
7.3 Accelerated Aging Factor (AAF) Determination:
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7.3.1 Using the Arrhenius equation with Q equal to 2 is a common and conservative means of calculating an aging factor.
10 10
NOTE 7—A more aggressive reaction rate coefficient, for example, Q = 2.2 to 2.5, may be used if the system under investigation is sufficiently well
characterized in the literature. The level and nature of damage must be similar to that reported in the literature to ensure that the reaction rate coefficient
and accelerated aging temperatu
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