SCHEDULE 3 Alert and information thresholds
Regulation 11(7)

PART 1 Alert thresholds for nitrogen dioxide and sulphur dioxide
Nitrogen dioxide	400 μg/m3 measured over three consecutive hours at locations representative of air quality over at least 100 km2 or an entire zone or agglomeration, whichever is the smaller
Sulphur dioxide	500 μg/m3 measured over three consecutive hours at locations representative of air quality over at least 100 km2 or an entire zone or agglomeration, whichever is the smaller

PART 2 Alert and information thresholds for ozone
	Parameter	Threshold
Alert threshold	1 hour average	240 μg/m3
Information threshold	1 hour average	180 μg/m3
(1) For the purposes of regulation 11 (action plans), exceedance of the 1 hour average in respect of the alert threshold is to be measured or predicted for three consecutive hours.		