The Compost Quality Assurance Organization was founded in order to monitor the quality of compost and digestate products. Through quality control and support of the producers of compost and digestate products in the marketing and application sectors, the organization aims to promote composting and anaerobic digestion as a key element of a sustainable biowaste management.

Bundesgütemeinschaft Kompost e.V. (BGK) has provided quality assurance for compost since 1992. In 2000 RAL labels for digestate products from biowaste and for digestate products from renewable energy crops were established. The RAL label for humus (sewage sludge compost) was introduced in 2003.