Best available techniques: environmental permits

‘Best available techniques’ (BAT) means the available techniques which are the best for preventing or minimising emissions and impacts on the environment. You need to use BAT if your operation is an installation (for example a facility that carries out an industrial process like a refinery, food factory or intensive farm).

‘Techniques’ include both the technology used and the way your installation is designed, built, maintained, operated and decommissioned.

The European Commission produces BAT reference documents or BREF notes. They contain BAT for installations. Any that were published before 1 January 2020 apply in the UK. For example, there’s a BREF for:

The European Commission has also published ‘BAT conclusions’ (BATC) documents which are legal requirements that your operation must meet. From 1 January 2020, UK BATC documents started to be produced – see UK BATC. These will have the same legal status as the EU BATC.

BATC contain a description of BAT and associated emission limits (‘BAT-AELs’) which you must comply with unless the Environment Agency agrees you’ve met certain criteria – see ‘How to propose an alternative technique’.

The guide for your activity will include a link to the BREF note or BATC for each activity (if there’s one available).

The UK regulators have agreed cross-cutting BATC interpretation guidance for the implementation of BAT and interpreting common issues arising in the interpretation of BREFs and BATC.

Your permit conditions may tell you what BAT you must use, or they may set emission limit values (ELVs) or other environmental outcomes based on BAT.

If your permit says you must follow BAT or ‘appropriate measures’ to achieve an outcome or ELV, check the guide for your activity for the BAT for that process.