What is the ASTM oxygen permeability?

ASTM International has developed a test method for measuring the oxygen permeability of plastic films and sheeting. The test method is described as ASTM D3985, titled "Standard Test Method for Oxygen Gas Transmission Rate Through Plastic Film and Sheeting Using a Coulometric Sensor."

The ASTM D3985 test method measures the rate at which oxygen gas can pass through a plastic film or sheeting under specific test conditions. It is commonly used to evaluate the barrier properties of plastic materials in applications where the prevention of oxygen ingress or egress is critical, such as food packaging or pharmaceutical packaging.

In this test method, the plastic film or sheeting is clamped over a test cell that separates two chambers: a high-pressure chamber containing oxygen gas and a low-pressure chamber, which serves as the receiver. The test cell is equipped with a coulometric oxygen sensor that measures the buildup of oxygen concentration in the receiver chamber over time. The rate of oxygen transmission is calculated based on the change in oxygen concentration and the test area of the sample.

The ASTM D3985 test method provides a quantitative measurement of the oxygen permeability of plastic films and sheeting. The results are usually reported in units of cubic centimeters of oxygen gas transmission per unit area, per unit time, under specified test conditions (such as temperature and relative humidity).

It's important to note that different ASTM standard test methods are available for measuring the permeability of other gases through plastic materials, such as carbon dioxide and water vapor. These test methods enable the assessment of the barrier properties of plastic materials against different gases, depending on the specific application requirements.