One is a sort of prohibited and referable materials list, things we either ban or would like to ban but cannot because of various materials. Sometimes these are materials which are the only thing to use, but we are trying to avoid the use of those products. There is also a sort of green list, if you like, of materials, things we would like to promote such as FSC certified timber, for example, or materials with a high recycle content. On the project I am working with we have worked previously with WRAP on looking at the percentage of recycled content by the value of the building and the client on my current project has a target or an aspiration to achieve 20%. So we are responding to those sorts of things. - https://goo.gl/UKg4kc

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Note added at 29 mins (2018-05-17 22:06:32 GMT)
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Black and grey lists

The car manufacturer Volvo pioneered the use of 'grey' and 'black' lists to filter out materials and chemicals that are not safe.
Black list substances should never be purchased and those on the grey list should only be used where no alternative exists. Anybody who wants a grey list substance should be required to provide a written justification for doing so. Some organisations help purchasers (and product designers) by providing a 'green list' or 'white list' of preferred substances.

Black and grey lists are highly industry specific, so you will need to research toxic materials in your business and determine which can and can't be replaced. Some sectoral bodies produce these lists, for example, the Oslo and Paris Commission (OSPAR) publishes black, grey and green lists for oil/gas drilling fluids.

https://goo.gl/AUNA4h

4.0 Definitions
Prohibited Materials (Mandatory “Black” List) - Materials and substances that are banned by the UK or European law. For list see paragraph 7.0.

Referable Materials (Advisory "Grey” List) - Materials and substances that, whilst not banned by legislation, are considered by Costain to be potentially hazardous or environmentally deleterious at one or more stages of their life cycle. For list of materials and substances see paragraph 8.0; the list includes supporting information indicating the rationale for appearing on this list. This list also includes guidance for some materials that should not be used in specific situations.

Preferred Materials (Green List) – Materials and substances that are considered by Costain to be preferable, due to their restricted environmental impact or environmental desirability. These materials and substances are outlined in paragraph 9.0 of this document.


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The following materials and substances are not currently banned by legislation, but in the specific circumstances described, are considered to be potentially hazardous and/or environmentally deleterious or technically undesirable at one or more stages of their life cycle. This list includes certain materials and substances that should be avoided in undesirable circumstances but may be acceptable in other circumstances. These materials should not be used without guidance from the SHE Department.

http://planning.islington.gov.uk/NorthgatePublicDocs/0032711...