ISO 15985 Anaerobic Biodegradability of Plastic Materials

Introduction to ISO 15985

ISO 15985 is the globally recognized norm that provides methodology for anaerobic biodegradability of plastic materials applied in high-solid conditions (like industrial anaerobic digesters). The growing use of biodegradable plastics has also led to a larger demand for standardized ways to measure and compare the environmentally friendly sensitivity of these materials. Standards like ISO 14855 (among others) are for aerobic degradation (in the presence of oxygen). However, most waste treatment plants are using anaerobic digestion due to its efficiency and gas production in modern days. Consequently, ISO 15985 fills the gap to offer methods for testing the anaerobic degradation (or nondegradation–the industry standards) of polymeric materials at high solids concentrations and thus allows authenticating biodegradability claims. 

ISO 15985 Test Method

ISO 15985  Equipment and Sample Preparation

ISO 15985  Results and Interpretation

The primary outcome for the ISO 15985 test is the percentage of anaerobic biodegradation shown as biogas production volume in comparison with the theoretical maximum. The criteria are: 

70% conversion to biogas: very good anaerobic biodegradability

40–70% conversion: Moderately biodegradable. 

Less than 40% conversion: Poorly or Non-biodegradable under anaerobic conditions 

Tests Related to ISO 15985 

 This test is equivalent to ASTM D5511, as both of them evaluate the anaerobic biodegradation of plastic materials under high-solids conditions, simulating the conditions found in anaerobic digesters and potentially active landfills.

Use of ISO 15985  in Various Industries

Generally, this test is used by  waste management sectors and the packaging industry 

Materials Commonly Tested with ISO 15985 

The most common materials used are plastic and polymer. Basically, the material that is obtained from organic compounds is tested.