ISO 14851:2019 specifies a method, by measuring the oxygen demand in a closed respirometer, for the determination of the degree of aerobic biodegradability of plastic materials, including those containing formulation additives in an aqueous system. The test mixture should contain an inorganic medium, the organic test material and activated sludge as the inoculum.

During the protocol, consumption of oxygen (BOD) is determined, by measuring the amount of oxygen required to maintain a constant volume of gas in the respirometer flasks, or by measuring the change in volume or pressure (or a combination of the two) either automatically or manually. The level of biodegradation is determined by comparing the BOD with the theoretical amount and expressed in percentage. 

The result of the protocol 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 14851. 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.