# Commission Implementing Decision (EU) 2017/1442 of 31 July 2017 establishing best available techniques (BAT) conclusions, under Directive 2010/75/EU of the European Parliament and of the Council, for large combustion plants (notified under document C(2017) 5225) (Text with EEA relevance), Division BAT 43: In order to prevent or reduce NOX emissions to air from the combustion of natural gas in engines, BAT is to use one or a combination of the techniques given below.

Extent: E+W+S+N.I.

Technique
Description
Applicability
a.
Advanced control system
See description in Section 8.3.
This technique is often used in combination with other techniques or may be used alone for combustion plants operated < 500 h/yr
The applicability to old combustion plants may be constrained by the need to retrofit the combustion system and/or control command system
b.
Lean-burn concept
See description in Section 8.3.
Generally used in combination with SCR
Only applicable to new gas-fired engines
c.
Advanced lean-burn concept
See descriptions in Section 8.3
Only applicable to new spark plug ignited engines
d.
Selective catalytic reduction (SCR)
Retrofitting existing combustion plants may be constrained by the availability of sufficient space.
Not applicable to combustion plants operated < 500 h/yr.
There may be technical and economic restrictions for retrofitting existing combustion plants operated between 500 h/yr and 1 500 h/yr

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Source: https://www.legislation.gov.uk/eudn/2017/1442/annex/division/4/division/4.1/division/4.1.2/division/3 (the official version)
Page: https://openlegislation.uk/eu-decision-2017-1442/annex/division-4/division-4.1/division-4.1.2/division-3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.