5.—(1) The regulator must, for the purpose of preventing or, where that is not practicable, reducing emissions into the air, exercise its relevant functions in relation to the installations to which this Schedule applies—
(a)so as to ensure that they are operated in such a way that—
(i)appropriate preventive measures are taken against air pollution, in particular through the application of best available techniques;
(ii)no significant air pollution is caused;
(b)where an environmental quality standard requires stricter conditions than those achievable by the use of best available techniques, additional measures are required by the permit, without prejudice to other measures which might be taken to comply with environmental quality standards;
(c)permits include emission limit values, which may if appropriate be supplemented or replaced by equivalent parameters or technical measures, for polluting substances likely to be emitted into the air from the installation concerned in significant quantities;
(d)where emissions of a greenhouse gas from an installation are specified in Annex 1 to Directive 2003/87/EC of the European Parliament and of the Council establishing a scheme for greenhouse gas emission allowance trading within the Community M1 in relation to an activity carried out in that installation, the permit does not include an emission limit value for direct emissions of that gas unless it is necessary to ensure that no significant local pollution is caused.
(2) The regulator must ensure that emission limit values or equivalent parameters or technical measures are based on best available techniques without prescribing the use of any technique or specific technology, but taking into account the technical characteristics of the installation, including (except in the case of mobile plant) its geographical location and the local environmental conditions.
(3) In this paragraph “substance” means any chemical element and its compounds and any biological entity or micro-organism, with the exception of the following substances—
(a)radioactive substances as defined in Article 1 of the Basic Safety Standards Directive;
(b)genetically modified micro-organisms as defined in Article 2(b) of Directive 2009/41/EC of the European Parliament and of the Council on the contained use of genetically modified micro-organisms M2;
(c)genetically modified organisms as defined in point 2 of Article 2 of Directive 2001/18/EC of the European Parliament and of the Council on the deliberate release into the environment of genetically modified organisms M3.