9.—(1) The Scottish Ministers must install sampling points in accordance with the criteria set out in Annex VIII to Directive 2008/50/EC.
(2) In zones where fixed measurement is the sole source of information for the assessment of air quality, the number of sampling points must be more than or equal to the minimum number specified in Section A of Annex IX to Directive 2008/50/EC.
(3) In zones where concentrations of ozone have been below the long-term objectives for each of the previous five years of measurement, the number of sampling points must be determined in accordance with the criteria set out in Section B of Annex IX to Directive 2008/50/EC.
(4) In zones where the information from fixed measurements is supplemented by information from modelling or indicative measurements or both, the number of sampling points referred to in paragraph (2) may be reduced provided that the following conditions are met:—
(a)the supplementary methods provide sufficient information for the assessment of air quality in relation to target values, long-term objectives, information and alert thresholds;
(b)the number of sampling points to be installed and the spatial resolution of supplementary methods are sufficient for the concentration of ozone to be established in accordance with the data quality objectives set out in Section A of Annex I to Directive 2008/50/EC and to enable assessment results to meet the criteria specified in Section B of the same Annex;
(c)there is at least one sampling point in each zone, with a minimum of one sampling point per two million inhabitants or one sampling point per 50,000km2, whichever produces the greater number of sampling points; and
(d)nitrogen dioxide is measured at all remaining sampling points except at rural background stations as referred to in Section A of Annex VIII to Directive 2008/50/EC.
(5) The Scottish Ministers must ensure that nitrogen dioxide is measured at no less than 50 per cent of the sampling points required under Section A of Annex IX to Directive 2008/50/EC.
(6) The measurement referred to in paragraph (5) must be continuous except at rural background stations.
(7) In choosing the location and number of sampling points for measurements of ozone precursor substances, the Scottish Ministers must take into account the objectives and methods set out in Annex X to Directive 2008/50/EC.