Green or Environmental claims should follow guidance that is issued by DEFRA. The latest publication was issued in February 2011 and is entitled: 'Green Claims Guidance - How to make a good environmental claim' and is available from: http://www.defra.gov.uk/environment/economy/green-claims-labels/.
The BCF has issued its own industry guidance on claims 'Guide on 'no added lead' and other environmental claims and statements in the Decorative Coatings Sector' and this is available from here.