In BPI’s “Ask the Expert” webcast on 4 October 2017, Mike Johnson (market development manager at Entegris Life Sciences) discussed single-use bags and gas permeation. Johnson’s Presentation Permeation rates are a function of fluid properties, the type of material being penetrated, and application temperature. Standardized test methods used to determine permeability characteristics include ASTM D1434 and ASTM D3985. A fixture in Entegris’s test apparatus holds a sample plaque that is flanked upstream by high-pressure gas and downstream by a sensor…