These Regulations implement in the United Kingdom Directive 2016/2284/EU of the European Parliament and the Council relating to national emission ceilings for certain atmospheric pollutants (OJ No L 344, 17.12.2016, p 1). This Directive implements at the EU level obligations under the United Nations Economic Commission for Europe 1979 Convention on Long-Range Transboundary Air Pollution and its 1999 Protocol to Abate Acidification, Eutrophication and Ground-level Ozone, which was revised in 2012.
Link: The National Emission Ceilings Regulations 2018
Source: Legislation .gov.uk
