3.—(1) The Secretary of State must—
(a)by 15th February each year prepare an inventory of emissions occurring within the United Kingdom of the pollutants specified in Table 1 of Schedule 1, for the calendar year before the previous calendar year;
(b)by 15th March 2019 and every two years after that date prepare and update a projection of emissions occurring within the United Kingdom of the pollutants set out in Table 2 of Schedule 1, for the years specified in column 3 of that table that have not yet passed.
(2) The inventories and projections referred to in paragraph (1) must be prepared or updated—
(a)in accordance with Parts 1 and 2 of Annex 4 to the Directive;
(b)without prejudice to sub-paragraph (a), in accordance with—
(i)the methodologies in the EMEP Reporting Guidelines;
(ii)the EMEP/EEA Guidebook.
(3) The Secretary of State must take appropriate steps to ensure that the inventories and projections referred to in this regulation are made available to the public.
4.—(1) Where the Secretary of State has prepared an inventory of emissions in accordance with regulation 3(1)(a) that shows an exceedance of a national emission ceiling or a national emission reduction commitment, the Secretary of State may prepare an adjusted inventory of emissions if—
(a)the exceedance is the result of applying improved inventory methods, or
(b)as regards an inventory for the calendar year 2025 or any subsequent year, the exceedance—
(i)is the result of applying significantly different emission factors or methodologies used for determining emissions from specific source categories compared with those which were expected as a result of the implementation of a norm or standard in source-based air pollution control legislation, and
(ii)does not arise from the way in which such legislation has been implemented or enforced in the United Kingdom.
(2) Where an adjusted inventory of emissions is prepared in accordance with this regulation, it replaces, for the purpose of Part 3 and 4, the inventory prepared under regulation 3, and references to an inventory in those Parts are to be read as references to the adjusted inventory of emissions.
(3) The Secretary of State must take appropriate steps to ensure an adjusted inventory of emissions is made available to the public and must publish alongside it the information set out in Schedule 2.
(4) In paragraph (1)(a), “improved inventory methods” means methods for preparing an inventory that have been updated in line with the EMEP Reporting Guidelines and EMEP/EEA Guidebook after 4th May 2012.