# Commission Delegated Regulation (EU) 2020/687 of 17 December 2019 supplementing Regulation (EU) 2016/429 of the European Parliament and the Council, as regards rules for the prevention and control of certain listed diseases (Text with EEA relevance), Division 1: Restricted zones as referred to in Article 85 must be defined on a case-by-case basis taking into account at least the following factors:

Extent: E+W+S+N.I.

(a) the accumulated number, the accumulated percentage and the distribution of the mortalities of molluscs/crustaceans/fish in the establishment or group of farming establishments infected with category A diseases;
(b) relevant information regarding movements to and from the infected establishment(s);
(c) the distance to and density of neighbouring establishments;
(d) the presence of wild aquatic animals;
(e) any knowledge concerning mortalities, suspected cases or outbreaks in wild aquatic animals which are, or could be related to the specific category A disease;
(f) the proximity to processing establishments, and the species present at those establishments, especially as regards listed species;
(g) farming practices applied in the affected and neighbouring establishments;
(h) hydrodynamic conditions and other identified factors of epidemiological significance.

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Source: https://www.legislation.gov.uk/eur/2020/687/annex/XIV/division/1 (the official version)
Page: https://openlegislation.uk/eu-regulation-2020-687/annex-XIV/division-1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.