1.1 ,This method covers a procedure for determination of the steady-state rate of transmission of carbon dioxide gas through plastics in the form of film, sheeting, laminates, coextrusions, or plastic-coated papers or fabrics. It provides for the determination of (1) carbon dioxide gas transmission rate (CO₂TR), (2) the permeance of the film to carbon dioxide gas (PCO₂), and (3) carbon dioxide permeability coefficient (P’,CO₂) in the case of homogeneous materials.