ISO 14852:2018 specifies a method for determining the biodegradability of a plastic material using aerobic, mesophilic microorganisms in an aqueous system. The test mixture contains an inorganic medium, the organic test material (the sole source of carbon and energy) with a concentration between 100 mg/l and 2000 mg/l of organic carbon, and the activated sludge or suspension of active soil or compost as the inoculum.

The mixture is agitated in test flasks and aerated with CO₂-free air over a period of time depending on the biodegradation kinetics, but not exceeding 6 months. The CO₂ evolved during the microbial degradation is determined by a suitable analytical method. The level of biodegradation is determined by comparing the amount of CO₂ evolved with the theoretical amount and expressed in percentage. The test result is the maximum level of biodegradation, determined from the plateau phase of the biodegradation curve.

BPC Blue is a fully automated biodegradability testing system suitable for ISO 14852. 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. The instrument is suitable for all test protocols which the measurement principle is based on oxygen demand measurement.