Assessment thresholds
10.—(1) The Scottish Ministers must classify each zone according to whether or not the upper and lower assessment thresholds specified in Section I of Annex II to Directive 2004/107/EC are exceeded in relation to arsenic, cadmium, nickel and benzo(a)pyrene.
(2) The Scottish Ministers must review the classification of zones carried out in accordance with paragraph (1) at least every five years, and must do so more frequently than every five years if there are significant changes in the activities which may affect levels of the pollutants referred to in paragraph (1) in ambient air.
(3) When considering the classification of zones in accordance with assessment thresholds, the Scottish Ministers must comply with Section II of Annex II to Directive 2004/107/EC.