# The Air Quality Limit Values (Wales) Regulations 2002, Part III: PARTICULATE MATTER (PM10)

Extent: E+W

Averaging period
Limit value
Margin of tolerance
Date by which limit value is to be met
1.24-hour limit value for the protection of human health
24 hours
50μg/m3 PM10, not to be exceeded more than 35 times a calendar year
10μg/m3 on 1st January 2003, reducing on 1st January of each following year by equal annual amounts to reach 0μg/m3 by 1st January 2005
1st January 2005
2.Annual limit value for the protection of human health
Calendar year
40μ g/m3 PM10
3.2μg/m3 on 1st January 2003, reducing on 1st January of each following year by equal annual amounts to reach 0μg/m3 by 1st January 2005
1st January 2005

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Source: https://www.legislation.gov.uk/wsi/2002/3183/schedule/1/part/III (the official version)
Page: https://openlegislation.uk/air-quality-limit-values-wales-regulations-2002/schedule-1/part-III
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.