The EU Directive (96/61 EC) on Integrated Pollution Prevention and Control (IPPC) allows local authorities to grant environmental permits to process industries, including new and existing petrochemical and chemical installations. The final permit sets Emission Limit Values (ELVs) that are defined on the basis of the Best Available Techniques (BAT). These BATs are a reference point against which to judge the current performance of an existing installation or to judge a proposal for a new installation. They result from an exchange of information between the European Commission, member states, industry and NGOs.