Introduction

Gas permeability is a critical property of plastic films and sheeting, especially in industries such as food packaging, 

pharmaceuticals, and medical devices, where barrier performance directly impacts product shelf life and quality. 

ISO 15105-2:2003 is an international standard that specifies a method for determining the gas-transmission rate 

(GTR) through plastic films using the equal-pressure method. This article explores the scope, principle, apparatus, 

and significance of this standard in material testing.

Scope of ISO 15105-2:2003

ISO 15105-2:2003 applies to the measurement of gas transmission through plastic films, sheets, and multilayer 

structures under steady-state conditions. The standard is suitable for both single gases and gas mixtures, providing 

a reliable way to assess material barrier properties.

Principle of the Equal-Pressure Method

Unlike differential-pressure methods (e.g., ISO 15105-1), the equal-pressure method maintains the same pressure on 

both sides of the test specimen. The key steps include:

Test Gas Exposure: The film is exposed to a test gas (e.g., O₂, CO₂, N₂) on one side while an inert carrier gas (e.g., 

nitrogen) flows on the other side.

Gas Permeation: The test gas molecules diffuse through the film and are carried by the inert gas to a detector.

Detection & Measurement: A gas chromatograph or infrared sensor quantifies the permeated gas, allowing the 

calculation of the gas-transmission rate.

Testing equipment:GTR-V3 Air permeability tester

Apparatus and Test Conditions

The standard specifies the following key components:

Permeation Cell: A sealed chamber that holds the test specimen and separates the test gas from the carrier gas.

Gas Supply System: Provides controlled test and carrier gas flows.

Detector: Measures the concentration of permeated gas (commonly using gas chromatography or infrared absorption).

Temperature & Humidity Control: Tests are typically conducted at 23°C ± 2°C and 50% ± 5% RH unless otherwise specified.

Significance and Applications

ISO 15105-2:2003 is widely used in:

Food Packaging: Ensures films provide adequate oxygen and moisture barriers to extend shelf life.

Pharmaceuticals: Evaluates blister packs and medical films for gas protection.

Industrial Films: Assesses barrier properties in agricultural films and protective coatings.

Conclusion

ISO 15105-2:2003 provides a precise and reproducible method for measuring gas permeability in plastic films under

 equal-pressure conditions. By standardizing test procedures, it enables manufacturers to compare material performance 

and optimize packaging solutions for enhanced product protection.

For accurate compliance, laboratories must follow the standard’s guidelines strictly, ensuring reliable and comparable

 results across the industry.