Operators of anaerobic digestion facilities can now attain a standard which proves that their digestate is safe to spread on land after WRAP this week published its long-awaited British Safety Standard for digestate.

The PAS110 certification scheme is being run by the Renewable Energy Association

Anaerobic digesters which meet the voluntary PAS 110 quality specification, which was originally drafted in April 2008, (see letsrecycle.com story) can assure users of digestate that their product is of a consistent quality and fit for purpose.

Operators which meet the standard and gain certification can say the digestate they produce meets a minimum standard and is safe for use as a fertiliser or soil improver.

In England and Wales the PAS 110 standard can be used alongside the 'Quality Protocol for production and use of quality outputs from anaerobic digestion', which was published in January last year (see letsrecycle.com story) and was designed to allow digestate, or biofertiliser which meets a certain standard, to be reclassified from a waste to a product.

It is hoped that the safety standard, along with the Quality Protocol will remove barriers to increasing anaerobic digestion in England, Scotland and Wales by helping to boost markets for digestate.

Producers that sign up to the PAS 110 will be expected to ensure that digested materials are made using suitable inputs and effectively processed by anaerobic digestion (AD) for sufficient time; and to ensure that the process has been well managed and monitored so as to produce digested material that meets market needs and protects the environment. Any producer who claims digested material conforms to PAS 110 must ensure that it is fit for purpose at all times.

Nina Sweet, organics technical specialist at WRAP, who helped to develop the PAS 110 along with technical manager Emily Nichols of the Association for Organics Recycling (AfOR), said: "The introduction of BSI PAS 110 is a fundamental step in helping to develop sustainable markets for biofertilisers. Making it easier for farmers to use biofertiliser will increase demand within the agricultural community for fertilising and soil conditioning products derived from waste material. This will reduce reliance on chemical fertilisers which has obvious environmental and economic benefits for the agricultural industry."

AD operators have welcomed the scheme; Jake Prior, operations director at Devon-based Andigestion which supplies 40 farms with digestate, commented that the PAS 110 will "provide important validation for farmers that biofertiliser is a safe, effective and environmentally friendly product".

He said the PAS 110 would save AD operators money because it would reduce the need to apply for waste exemptions on behalf of the agricultural sector which cost up to £500 each.

Mr Prior added: "It will also make it economically viable for us to supply farmers who want to use smaller amounts of biofertiliser. Until now, we've had to restrict ourselves to larger-scale users as the exemptions apply to 50 hectare blocks of land."

The Renewable Energy Association (REA) is running an independent certification scheme for biogas plants that wish to comply with the PAS 110 and the Quality Protocol.

David Collins, the expert on anaerobic digestion at the REA, said: "BSI PAS 110 and the ADQP are extremely important developments within the AD industry. They provide assurance to consumers, farmers, food producers and retailers alike that biofertiliser is a safe and good quality product."

The PAS 110 has been sponsored by WRAP and Renewables East. It has been developed in conjunction with the REA and the Association for Organics Recycling in collaboration with the British Standards Institution (BSI).