# The Environmental Targets (Fine Particulate Matter) (England) Regulations 2022, Regulation 10: Interpretation of this Part


In this Part and in Schedule 1—
“the baseline period” has the meaning given in regulation 7;
“population exposure” means population exposure to PM2.5;
“the Population Exposure Indicator”—
(a) for the baseline period is a measure of average population exposure in that period;
(b) for a year from 2019 onwards is a measure of average population exposure in the three-year period ending on 31st December in that year,
calculated in accordance with Schedule 1;
“the Reference Indicator” for a year is a measure of average population exposure in the three-year period ending on 31st December in the preceding year, calculated in accordance with Schedule 1 and to be used only for the purposes of making the determination required by regulation 8(1)(a) and the calculations required by paragraphs 1(d) and 2(c) of Schedule 1.

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Source: https://www.legislation.gov.uk/ukdsi/2022/9780348242959/regulation/10 (the official version)
Page: https://openlegislation.uk/draft-environmental-targets-fine-particulate-matter-england-regulations-2022/regulation-10
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.