The Air Quality Standards (Wales) Regulations 2010

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

SCHEULE 2E+WTarget values

Arsenic, cadmium, nickel and benzo(a)pyrene

PollutantTarget value for the total content in the PM10 fraction averaged over a calendar yearDate by which target value should be met
Arsenic6 ng/m331 December 2012
Cadmium5 ng/m331 December 2012
Nickel20 ng/m331 December 2012
Benzo(a)pyrene1 ng/m331 December 2012

Ozone

ObjectiveAveraging periodTarget value
Protection of human healthMaximum daily eight hour mean M1120 μg/m3, not to be exceeded on more than 25 days per calendar year averaged over three years M2
Protection of vegetationMay to JulyAOT 40 (calculated from 1h values) 18,000 μg/m3 · h averaged over five years M2

PM2·5

Averaging periodTarget value
Calendar year25 μg/m3

Marginal Citations

M1The 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.

M2If 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.