Oxygen transmission rate
Oxygen transmission rate (OTR) is the measurement of the amount of oxygen gas that passes through a substance over a given period. It is mostly carried out on non-porous materials, where the mode of transport is diffusion, but there are a growing number of applications where the transmission rate also depends on flow through apertures of some description.
Standard test methods are available for measuring the oxygen transmission rate of packaging materials. Completed packages, however, involve heat seals, creases, joints, and closures which often reduce the effective barrier of the package. For example, the glass of a glass bottle may have an effective total barrier but the screw cap closure and the closure liner might not.
ASTM standard test methods include:
- D3985 Standard Test Method for Oxygen Gas Transmission Rate Through Plastic Film and Sheeting Using a Coulometric Sensor
- F1307 Standard Test Method for Oxygen Transmission Rate Through Dry Packages Using a Coulometric Sensor
- 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
- F2622 Standard Test Method for Oxygen Gas Transmission Rate Through Plastic Film and Sheeting Using Various Sensors
Other test methods include:
- The ambient oxygen ingress rate method (AOIR) an alternative method for measuring the oxygen transmission rates (OTR) of whole packages
Also a factor of increasing awareness in the debate surrounding wine closures, natural corks show small variation in their oxygen transmission rate, which in turn translates to a degree of bottle variation.
- Yam, K. L., "Encyclopedia of Packaging Technology", John Wiley & Sons, 2009, ISBN 978-0-470-08704-6
- Massey,L K, "Permeability Properties of Plastics and Elastomers", 2003, Andrew Publishing, ISBN 978-1-884207-97-6
- Sanghyun Lee "Mass Transfer" Konkuk University, 2017
- Hanne Larsen, Achim Kohlr and Ellen Merethe Magnus, "Ambient oxygen ingress rate method", John Wilew & Sons, Packaging Technology and Science, Volume 13 Issue 6, Pages 233 - 241