ISO 13975:2019 defines a method for identifying the ultimate biodegradability of plastic materials under anaerobic conditions in a controlled anaerobic slurry digestion system. 

The methanogenic inoculum is obtained from an anaerobic digester operating on sewage sludge or on organic waste such as livestock manure or garbage. The test material mixed with the inoculum is anaerobically incubated in a test vessel at a pre-selected temperature for a test period until a plateau phase of gas production is reached, but the total period shall be normally 60 days and not exceed 90 days.

The digestion temperature can be either thermophilic or mesophilic condition in order to simulate these two different digestion conditions. The amount of biogas produced is calculated from the volume of biogas collected and the amount of dissolved inorganic carbon (DIC) formed in excess of blank values. The percentage of biodegradation is calculated as the ratio of the sum of the net increase of produced biogas and DIC to the theoretical amount of evolved biogas.

BPC Blue is a fully automated biodegradability testing system suitable for ISO 13975. It allows for continuous and on-line monitoring of released biogas (CH₄ and CO₂) and is a fully integrated and automated system for sampling, analysing, recording, and generating reports. BPC Blue is the perfect analytical tool that offers standardised measurement procedures, data interpretations and reports.