Composting and Certification

The British Standard Institution published a specification for compost materials known as BSI PAS 100 which applies across the UK. The aim of the BSI PAS 100 is to try and improve confidence in composted materials among end users, specifiers and blenders. Also it will help producers distinguish products that are safe, reliable and high performance from those that are not (Website 1).

The Standard covers the whole of the life cycle by which composting is produced from the production methods, through to quality control and laboratory testing (Website 2). The material must be sampled and tested to make sure that the product fits with the BSI PAS 100 criteria and therefore is fit for use. PAS 100 is only for biodegradable materials that have been kept separate from non-biodegradables. It applies to composted materials produced at centralised, on-farm and community composting facilities; it does not extend to end products of home composting for self-use (Website 1).

The Composting Association run a certification scheme, it is only a UK scheme providing third party assessment and agreement with BSI PAS 100. The process involves an annual inspection of the compost producers (Website 2).

If the compost has been treated to BSI PAS 100 standards then it will have the below certification mark issued from The Composting Association (Website 2).

At present in Scotland and Northern Ireland the only recognised standard for compost is the BSI PAS 100 standard, any compost used that does not comply with PAS 100 must be used in compliance with Waste Management Licensing Regulations (Website 3, 4). Scotland uses the basis BSI PAS 100 to allow such compost to no longer be regarded as a waste (Website 3).

Quality Protocol Compost

In England and Wales the quality protocol for the production and use of quality compost from source-segregated biodegradable waste has been recognised by the Environment Agency since the 7 May 2007 (Website 5). The Environment and Heritage Service in Northern Ireland plan to review their current position on the regulation of outputs from the composting of waste and this review will take the Quality Protocol into consideration (Website 5).

The quality protocol for compost has been developed so that materials produced in accordance with the quality protocol will no longer be considered as waste. It was also developed to try and help reduce the regulatory burden for the production and use of quality compost (Website 5). It also helps provide users with confidence that the compost they purchase conforms to an approved standard and helps to protect the environment and human health by describing acceptable best practice for the use of the compost (Website 6).

Registering for the Quality Protocol for Compost

If the compost producers is already certified to BSI PAS 100 or is in the process of gaining certification and they want to register under the quality protocol also they will have to (Website 7):

  • check that they are only composting types of waste that are allowed in the protocol
  • ensure that they keep the additional records required from 11 May 2007 onwards.

If the compost producer is not in the process of attaining BSI PAS 100 certification then they have to be registered with a certification body and pay their registration fee by the 15 November 2007. For compost producers who have not registered then the only way there compost can be used is if they (Website 7):

have an exemption from the Environment Agency to spread to land

their site has moved to a licensed waste management site for disposal

Once producers have registered on the scheme they can demonstrate they are in accordance with the quality protocol (Website 6):

  • by obtaining certification from an approved certification body
  • by producing and keeping copies of contracts of supply or information to customers which includes a declaration of conformance with this Quality Protocol.

Criteria for Producing Quality Compost

Compost which meets the criteria of the quality protocol will normally be regarded as having ceased to be waste. This means that the compost will no longer be subject to waste regulatory controls when dispatched to the customer. For this to be the case the compost must the following criteria are met (Website 6):

  • The compost is produced using only certain types of source-segregated input materials
  • The compost meets the requirements of an approved standard, producers should be aware that standards are subject to regular periodic review and should ensure they comply with the latest version
  • Compost must be destined for appropriate use within one or more of the following market sectors:
  • land restoration and soft landscape operations;
  • horticulture (this includes domestic use);
  • agriculture and soil-grown horticulture.


Website 1, WRAP, Producing Quality Compost, (Accessed 11/10/07)

Website 2, WRAP, Introduction to PAS 100:2005, Summary of the BSI specification for composted materials, Accessed 11/10/07)

Website 3, The Scottish Government (2007), Annex C: Community Composting, (Accessed 11/10/07)

Website 4, Environment and Heritage Services (2005), Waste Management and Contaminated Land Composting Guidance, (Accessed 11/10/07)

Website 5,The Quality Protocol for the production and use of quality compost from source-segregated biodegradable waste, frequently asked questions, (Accessed 09/10/2007)

Website 6, Environment Agency and WRAP, Quality Protocol Compost, The quality protocol for the production and use of quality compost from source-segregated biodegradable waste, (Accessed 09/10/2007)

Website 7 Environment Agency, Compost leads the way with first Quality Protocol, (Accessed 11/10/2007)