The Department shall classify each zone according to whether or not the upper and lower assessment thresholds specified in Section 1 of Annex II to Council Directive 2004/107/EC are exceeded in relation to arsenic, cadmium, nickel and benzo(a)pyrene.

The Department shall review the classification of zones in paragraph (1) every five years, and shall 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.

When classifying zones in accordance with assessment thresholds, the Department shall comply with Section II of Annex II to Council Directive 2004/107/EC.