The document discusses methods for testing the water vapour transmission rate (WVTR) and oxygen transmission rate (OTR) of materials. It describes how WVTR is measured through containers using a test apparatus that places material samples between a desiccant and humid environment. OTR is measured similarly using an electrolytic sensor to detect oxygen permeating through materials. Factors like material thickness, humidity, and temperature that affect transmission rates are identified. Standards for conducting these transmission tests are also outlined.