The Air Quality Standards (Wales) Regulations 2010

Regulations 14, 20(1) and (3), 21(5), 23(1) and, 24(2)

SCHEULE 2 Target values

Arsenic, cadmium, nickel and benzo(a)pyrene

Pollutant	Target value for the total content in the PM10 fraction averaged over a calendar year	Date by which target value should be met
Arsenic	6 ng/m3	31 December 2012
Cadmium	5 ng/m3	31 December 2012
Nickel	20 ng/m3	31 December 2012
Benzo(a)pyrene	1 ng/m3	31 December 2012

Ozone

Objective	Averaging period	Target value
Protection of human health	Maximum daily eight hour mean(1)	120 μg/m3, not to be exceeded on more than 25 days per calendar year averaged over three years(2)
Protection of vegetation	May to July	AOT 40 (calculated from 1h values) 18,000 μg/m3 · h averaged over five years(2)

PM_2·5

Averaging period	Target value
Calendar year	25 μg/m3

(1)

The maximum daily eight hour mean concentration must be selected by examining eight hour running averages, calculated from hourly data and updated each hour. Each eight hour average so calculated must be assigned to the day on which it ends, that is, the first calculation period for any one day will be the period from 17:00 on the previous day to 01:00 on that day, and the last calculation period for any one day must be the period from 16:00 to 24:00 on that day.

(2)

If the three or five year averages cannot be determined on the basis of a full and consecutive set of annual data, the minimum annual data required for checking compliance with the target values will be valid data for one year in relation to the target value for the protection of human health and valid data for three years in relation to the target value for the protection of vegetation.