ASTM D-5338-15 test method is equivalent to ISO 14855, which determines the degree and rate of aerobic biodegradation of plastic materials on exposure to a controlled-composting environment under laboratory conditions, at thermophilic temperatures.

Test substances are exposed to an inoculum that is derived from compost from municipal solid waste. The aerobic composting takes place in an environment where temperature, aeration and humidity are closely monitored and controlled. The percentage of biodegradability is obtained by determining the percentage of carbon in the test substance that is converted to CO₂ during the duration of the test. 

BPC Blue is a fully automated biodegradability testing system suitable for ISO ASTM D5338 and may be configured to evaluate aerobic biodegradability of polymer samples under the same temperature range of controlled composting conditions using industrial compost as inoculum. Utilising an in-situ carbon dioxide absorption kit, BPC Blue functions as a closed-respirometer for continuous and on-line measurement of oxygen consumption or depletion caused by aerobic respiration of microorganisms.