These are the primary test standards used by the test facilities to measure biodegradation and compostability:
| Test Standards | Descriptions |
|---|---|
| ASTM-D5338 | A biodegradation test that measures the natural elements that are converted into gas to indicate how much of a product is actually biodegraded in industrial compost conditions (aerobic conditions). The ASTM-D5338 test does not include any testing for disintegration. ASTM-D5338 is not a pass/fail test. The reports indicate what percentage biodegraded over the tested time period, which can be selected by the test requestor. |
| ASTM-D5511 | A biodegradation test that is performed in conditions that simulate anaerobic digestion. This is not a pass/fail test. The reports indicate what percentage biodegraded over the tested time period. |
| ASTM-D5338 and ASTM-D5511 (measurement of the amount biodegraded ) | Biodegradation results are compared to negative and positive controls that are tested along with the sample that is being biodegraded to confirm that the test results will be acceptable. 90% biodegradation compared to the positive sample is considered fully biodegraded. Please note that even the control samples may not 100% convert into gas, but they are actually completely biodegraded and are known as materials (usually cellulose) that are 100% biodegradable. The amount of product that is shown in the test reports as being biodegraded requires complete conversion from plastic into natural elements such as CO2, CH4 and water. Once converted into natural elements through biodegradation, small fragments (including microfragments) do not remain, because they have been completely converted (biodegraded) back into natural elements. Scientists believe that 90% biodegradation compared to the cellulose (positive sample) indicates full biodegradation. |
Testing and certification is performed by several organizations which include:
| Test Facilities | Description |
|---|---|
| Eden Research Laboratories | |
| NSF International | |
| OWS |
| Certifying Bodies | Description |
|---|---|
| Vinçotte (TÜV Austria) | A non-profit accredited inspection and certification organization that has several offices located through Europe. They review test results performed by test facilities and issue several different certifications including: OK COMPOST, OK BIOBASED and OK BIODEGRADABLE. |
| Din Certco (TUV Rheinland) | A certifying body located in Germany. They review test results performed by test facilities and issue certifications for: “Seedling” and /or DIN-Geprüft mark. |
| Biodegradable Products Institute (BPI) | Located in the USA and uses test results from certain test facilities to certify the compostability of plastic products. BPI reviews test results that were performed by approved test facilities and issues a certification for products to be Compostable. |