# The Environmental Authorisations (Scotland) Regulations 2018, Chapter Tables Table 1 Emission limit values (mg/Nm3) for existing medium combustion plants with a rated thermal input equal to or greater than 1 MW and less than or equal to 5 MW, other than engines and gas turbines (1)The value does not apply in the case of plants firing exclusively woody solid biomass. (2)300 mg/Nm3 in the case of plants firing straw. (3)400 mg/Nm3 in the case of low calorific gases from coke ovens in the iron and steel industry. Pollutant Solid biomass Other solid fuels Gas oil Liquid fuels other than gas oil Natural gas Gaseous fuels other than natural gas SO2 200 1100 - 350 - 200 NOx 650 650 200 650 250 250 Dust 50 50 - 50 - - Table 2 Emission limit values (mg/Nm3) for existing medium combustion plants with a rated thermal input greater than 5 MW, other than engines and gas turbines (1)The value does not apply in the case of plants firing exclusively woody solid biomass. (2)300 mg/Nm3 in the case of plants firing straw. (3)1,100 mg/Nm3 in the case of plants with a rated thermal input greater than 5 MW and less than or equal to 20 MW. (4)Until 1 January 2030, 850 mg/Nm3 in the case of plants with a rated thermal input greater than 5 MW and less than or equal to 20 MW firing heavy fuel oil. (5)400 mg/Nm3 in the case of low calorific gases from coke ovens, and 200 mg/Nm3 in the case of low calorific gases from blast furnaces, in the iron and steel industry. (6)170 mg/Nm3 in the case of biogas. (7)50 mg/Nm3 in the case of plants with a rated thermal input greater than 5 MW and less than or equal to 20 MW. Pollutant Solid biomass Other solid fuels Gas oil Liquid fuels other than gas oil Natural gas Gaseous fuels other than natural gas SO2 200 400 - 350 - 35 NOx 650 650 200 650 200 250 Dust 30 30 - 30 - - Table 3 Emission limit values (mg/Nm 3) for existing engines and gas turbines (1)60 mg/Nm3 in the case of biogas. (2)130 mg/Nm3 in the case of low calorific gases from coke ovens, and 65 mg/Nm3 in the case of low calorific gases from blast furnaces, in the iron and steel industry. (3)1,850 mg/Nm3 in the following cases— (i) for diesel engines the construction of which commenced before 18 May 2006, (ii) for dual fuel engines in liquid mode. (4)250 mg/Nm3 in the case of engines with a rated thermal input equal to or greater than 1 MW and less than or equal to 5 MW. (5)250 mg/Nm3 in the case of engines with a rated thermal input equal to or greater than 1 MW and less than or equal to 5 MW, 225 mg/Nm 3 in the case of engines with a rated thermal input greater than 5 MW and less than or equal to 20 MW. (6)380 mg/Nm3 for dual fuel engines in gas mode. (7)Emission limit values are only applicable above 70 % load. (8)20 mg/Nm3 in the case of plants with a rated thermal input equal to or greater than 1 MW and less than or equal to 20 MW. Pollutant Type of medium combustion plant Gas oil Liquid fuels other than gas oil Natural gas Gaseous fuels other than natural gas SO2 Engines and gas turbines - 120 - 15 NOx Engines 190 190 190 190 NOx Gas Turbines 200 200 150 200 Dust Engines and gas turbines - 10 - - Table 4 Emission limit values (mg/Nm3) for new combustion plants other than engines and gas turbines (1)The value does not apply in the case of plants firing exclusively woody solid biomass. (2)Until 1 January 2025, 1700 mg/Nm3 in the case of plants which are part of SIS or MIS. (3)400 mg/Nm3 in the case of low calorific gases from coke ovens, and 200 mg/Nm3 in the case of low calorific gases from blast furnaces, in the iron and steel industry. (4)100 mg/Nm3 in the case of biogas. (5)500 mg/Nm3 in the case of plants with a total rated thermal input equal to or greater than 1 MW and less than or equal to 5 MW. (6)Until 1 January 2025, 450 mg/Nm3 when firing heavy fuel oil containing between 0.2 % and 0.3 % N and 360 mg/Nm3 when firing heavy fuel oil containing less than 0.2 % N in the case of plants which are part of SIS or MIS. (7)50 mg/Nm3 in the case of plants with a total rated thermal input equal to or greater than 1 MW and less than or equal to 5 MW; 30 mg/Nm3 in the case of plants with a total rated thermal input greater than 5 MW and less than or equal to 20 MW. (8)50 mg/Nm3 in the case of plants with a total rated thermal input equal to or greater than 1 MW and less than or equal to 5 MW. Pollutant Solid biomass Other solid fuels Gas oil Liquid fuels other than gas oil Natural gas Gaseous fuels other than natural gas SO2 200 400 - 350 - 35 NOx 300 300 200 300 100 200 Dust 20 20 - 20 - - Table 5 Emission limit values (mg/Nm 3) for new engines and gas turbines (1)Until 1 January 2025, 590 mg/Nm3 for diesel engines which are part of SIS or MIS. (2)40 mg/Nm3 in the case of biogas. (3)Engines running between 500 and 1,500 hours per year may be exempted from compliance with those emission limit values if they are applying primary measures to limit NOx emissions and meet the emission limit values set out in footnote (4). (4)Until 1 January 2025 in SIS and MIS, 1,850 mg/Nm3 for dual fuel engines in liquid mode and 380 mg/Nm3 in gas mode; 1,300 mg/Nm3 for diesel engines with ≤ 1200 rpm with a total rated thermal input less than or equal to 20 MW and 1,850 mg/Nm3 for diesel engines with a total rated thermal input greater than 20 MW; 750 mg/Nm3 for diesel engines with > 1,200 rpm. (5)225 mg/Nm3 for dual fuel engines in liquid mode. (6)225 mg/Nm3 for diesel engines with a total rated thermal input less than or equal to 20 MW with ≤ 1,200 rpm. (7)190 mg/Nm3 for dual fuel engines in gas mode. (8)These emission limit values are only applicable above 70 % load. (9)Until 1 January 2025, 550 mg/Nm3 for plants which are part of SIS or MIS. (10)Until 1 January 2025, 75 mg/Nm3 for diesel engines which are part of SIS or MIS. (11)20 mg/Nm3 in the case of plants with a total rated thermal input equal to or greater than 1 MW and less than or equal to 5 MW. Pollutant Type of medium combustion plant Gas oil Liquid fuels other than gas oil Natural gas Gaseous fuels other than natural gas SO2 Engines and gas turbines - 120 - 15 NOx Engines 190 190 95 190 NOx Gas turbines 75 75 50 75 Dust Engines and gas turbines - 10 - - --- Source: https://www.legislation.gov.uk/ssi/2018/219/schedule/27/part/3/chapter/Tables (the official version) Page: https://openlegislation.uk/environmental-authorisations-scotland-regulations-2018/schedule-27/part-3/chapter-Tables Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.