Industrial installations
For industrial installations, EU-wide emission limit values were established only for very few types of installations, as Member States were reluctant to accept such emission limit values for stationary sources. Such emission limit values are set by two directives: The Industrial Emissions Directive (2010/75/EU, IED) and the Medium Combustion Plant Directive (2015/2193, MCPD). The MCPD, which was proposed as part of the Clean Air Policy Package in 2013, fills the regulatory gap at EU level between large combustion plants (> 50 MWth), covered by the IED and smaller appliances (heaters and boilers <1 MWth) covered by the Ecodesign Directive (2009/125/EC). Other small-sized industrial installations are generally only subject to air emission restrictions according to national law - where such restrictions exist.
The IED lays down rules to prevent or, where that is not practicable, to reduce industrial emissions into air, water and land and to prevent the generation of waste, in order to achieve a high level of environmental protection. It sets limit values for large combustion plants, for waste incinerators, installations and activities that use organic solvents, and installations for the production of titanium dioxide 
. The emission limit values concern sulfur dioxide, nitrogen oxides, carbon monoxide and particulates; for waste incinerators, also emission limit values for dioxins and furans - two highly toxic chemical substances generated by the incineration process - as well as for a number of heavy metals were fixed. The provisions are sometimes very differentiated, according to the fuel used, the question, whether an "indigenous" fuel (coal) was used, the age or size of the installation etc.
The IED aims to increase the effectiveness of the legislation by supporting Member States in implementing BAT-based permitting. For these large industrial installations, the general approach taken by the EU is that the installations had to comply with the best available technique not entailing excessive costs. For the different types of installations that are covered by the Directive, guidance documents on industrial processes are elaborated by national and EU public authorities, experts, industry representatives and environmental organisations (BREF). The conclusions are formally adopted by the EU (BAT conclusions - BATC) and shall, in principle, serve as a basis for the emission limit values that are fixed in the permits which the national authorities grant to an individual installation.
The MCPD regulates pollutant emissions from the combustion of fuels in plants with a rated thermal input equal to or greater than 1 Megawatt thermal (MWth) and less than 50 MWth. The MCPD regulates emissions of SO2, NOX and dust to air. It aims to reduce those emissions and the resultant risks to human health and the environment. It also requires monitoring of carbon monoxide (CO) emissions. The emission limit values set in the MCPD apply from December 2018 for new plants and 2025 or 2030 for existing plants, depending on their size. The flexibility provisions for district heating plants and biomass firing ensure that climate and air quality policies are consistent and their synergies are maximised. The MCPD also implements obligations arising from the Gothenburg Protocol under the UNECE Convention on Long-Range Transboundary Air Pollution.
The Member States must ensure that all new medium combustion plants put into operation after 19 December 2018 have a permit or are registered: the first group (with input or capacity greater than 5 MW) by 1 January 2024, the second group (with input less than or equal greater to 5 MW) by 1 January 2029. Each EU country’s competent authority must hold a publicly available register with information on each plant, such as the type of fuel used and the expected number of annual operating hours. The legislation sets out emission limit values by fuel category, also distinguishing between new and existing plants. Some plants may be exempted from the limits. The limit values apply from 20 December 2018 for new plants and by 2025 or 2030 for existing plants, depending on their size. Furthermore, effective inspections must be established to check compliance with emission limit values. The Member States must provide the Commission with several reports: with an estimate of the total amount of annual emissions of CO (by 1 January 2021), with qualitative and quantitative information on the directive's implementation (by 1 October 2026), with a second report on implementation (by 1 October 2031).