ASTM F1927 - Standard Test Method for Determination of O2GTR, Permeability and Permeance at Controlled Relative Humidity Through Barrier Materials

ASTM F1927

Standard Test Method for Determination of Oxygen Gas Transmission Rate, Permeability, and Permeance at Controlled Relative Humidity Through Barrier Materials Using a Coulometric Detector

This test method covers a procedure for determination of the rate of transmission of oxygen gas, at steady-state, at a given temperature and %RH level, through film, sheeting, laminates, co-extrusions, or plastic-coated papers or fabrics. This test method extends the common practice of dealing with zero humidity or, at best, an assumed humidity. Humidity plays an important role in the oxygen gas transmission rate (O2GTR) of many materials.

This test method provides for the determination of oxygen gas transmission rate (O2GTR), the permeance of the film to oxygen gas (PO₂), the permeation coefficient of the film to its thickness (P”O₂), and oxygen permeability coefficient (PʹO₂) in the case of homogeneous materials at given temperature and %RH level(s).

What is ASTM F1927?

ASTM F1927 is a standard test method established by ASTM International (formerly known as the American Society for Testing and Materials) to determine the oxygen gas transmission rate (O2GTR) through plastic films and sheeting. This method is essential for industries that manufacture packaging materials, particularly those used for food, pharmaceuticals, and other products sensitive to oxygen exposure. Oxygen permeation can lead to spoilage, oxidation, and degradation, making it crucial for packaging engineers and material scientists to assess the barrier properties of packaging films.

The standard provides detailed procedures for determining how much oxygen can pass through a given material under specific temperature and humidity conditions. This allows manufacturers to evaluate the suitability of their packaging materials in preserving product quality, prolonging shelf life, and protecting contents from oxygen-related damage.

Determination of Oxygen Gas Transmission Rate

The oxygen gas transmission rate (O2GTR) is a measure of the amount of oxygen gas that permeates through a material over a specified period of time. In the context of ASTM F1927, the OTR is typically measured in units of cubic centimeters per square meter per day (cc/m²/day). The procedure involves exposing one side of the plastic film to oxygen gas while maintaining an inert gas, such as nitrogen, on the opposite side. A sensor detects the oxygen that diffuses through the film, and the rate of oxygen transmission is calculated.

Key parameters such as temperature, humidity, and the thickness of the film significantly affect the OTR measurement. These factors must be controlled and recorded during testing to ensure the accuracy and reliability of the results. The method is commonly used with films that require high oxygen barrier properties, such as those in the food industry, where packaging integrity is critical to preventing spoilage.