Industrial composting is an established process with commonly agreed requirements concerning temperature and timeframe for biodegradable waste to metabolise to stable, sanitised products (biomass) to be used in agriculture (humus/fertiliser). This process takes place in industrial or municipal composting plants. These plants provide controlled conditions, i.e. controlled temperatures, humidity, aeration, etc. for a quick and safe composting process.
The criteria for the industrial compostability of packaging are set out in the European standard EN 13432. EN 13432 requires the compostable plastics to disintegrate after 12 weeks and completely biodegrade after six months. That means that 90 percent or more of the plastic material will have been converted to CO2. The remaining share is converted into water and biomass – i.e. valuable compost. Materials and products complying with this standard can be certified and labelled accordingly.
There is currently no international standard specifying the conditions for home composting of biodegradable plastics. However, there are several national standards, such as the Australian norm AS 5810 “Biodegradable plastics – biodegradable plastics suitable for home composting”. Belgian certifier TÜV Austria Belgium had developed the OK compost home certification scheme, requiring at least 90% degradation in 12 months at ambient temperature. Based on this scheme, the French standard NF T 51-800 “Plastics — Specifications for plastics suitable for home composting” was developed, specifying the very same requirements for certification.