SPMC's FAQs provide guidance for your technical challenges.

What are generally recognized storage conditions of flexible barrier materials?

Last Updated On August 15, 2023

Download the infographic created for this FAQ.

Most packaging suppliers provide guidance on the storage conditions for their pre-made sterile barrier systems and rollstock. The intention is to provide information on environmental conditions (and possibly a timeframe, such as 1-year from date of manufacture) that may affect performance expectations of these materials. Since a supplier has little direct knowledge of how a customer will be storing flexible packaging materials, the recommended storage conditions and a time limit on warranty are created for guidance. The information is not intended to be limiting or to be construed as measures to preserve the product contained in the packaging. In addition, environmental conditions for material staging, a “Best Used” scenario, may also be recommended in order for materials to be at their optimum condition for manufacturing. Users of packaging materials and pre-made sterile barrier systems must ensure that all layers of packaging (primary, secondary, tertiary, as applicable) are evaluated through distribution and that appropriate aging studies are completed.

Recommendations for storage conditions vary due to the range of applications and environmental conditions as noted below. These points are created to define the conditions for a majority of packaging materials. Highly sensitive materials should be labelled for special handling in storage. Exceptions would need to be studied and defined separately within customer-supplier agreements. Excursions of a limited time such as those expected in shipping are not generally damaging to packaging materials however where excursions occur over a long period of time, an assessment of the effects on the packaging materials may be needed.

• Material should be stored at a range of 50-80°F (~10-27°C). In general, temperatures lower than 50oF are not known to cause damage to most polymers used in flexible packaging. However, the need for (and length of time for) conditioning the material before processing may increase when materials are stored beyond this range.
• Material should generally be stored at a range of 40-70% relative humidity. However, if materials are known to be sensitive to ambient humidity conditions at low and/or high levels, more specific storage conditions may be required, as outlined in customer-supplier agreements. While packaging is often exposed to high levels of temperature and humidity in sterilization cycles such as those in steam/autoclave or ethylene oxide pre-humidification and sterilization cycles, warehouse inventory storage conditions are normally well below these challenges and could instead be monitored to be within a maximum absolute humidity measurement of the worst case material/exposure to address this criteria.
• Material should be wrapped in a protective coating (i.e. shrink wrap or secured poly bags) and re-wrapped during storage. Note: A moisture resistant wrapping material provides added protection for hygroscopic materials (i.e. paper, EVOH, nylon, etc.). Materials requiring protection from light exposure would need an effective shroud.
• Material should be stored in a clean environment and be protected from excessive dust, debris or other contaminants.
• Material should be brought into an environment with the temperature and relative humidity recommendations outlined above 24-48 hours before use.