Article 4 Setting of threshold values through ... regional or subregional cooperationF14

be part of the set of characteristics used by the Secretary of State, in consultation with the devolved policy authorities, in their determination of good environmental status;

be consistent with F4F5assimilated law;

where appropriate, distinguish the quality level that reflects the significance of an adverse effect for a criterion and be set in relation to a reference condition;

be set at appropriate geographic scales of assessment to reflect the different biotic and abiotic characteristics of the regions, subregions and subdivisions;

be set on the basis of the precautionary principle, reflecting the potential risks to the marine environment;

be consistent across different criteria when they relate to the same ecosystem element;

make use of best available science;

be based on long time-series data, where available, to help determine the most appropriate value;

reflect natural ecosystem dynamics, including predator-prey relationships and hydrological and climatic variation, also acknowledging that the ecosystem or parts thereof may recover, if deteriorated, to a state that reflects prevailing physiographic, geographic, climatic and biological conditions, rather than return to a specific state of the past;

be consistent, where practical and appropriate, with relevant values set under regional institutional cooperation structures, including those agreed in the Regional Sea Conventions.

national threshold values, provided the obligation of regional cooperation laid down in Articles 5 and 6 of Directive 2008/56/EC is complied with;

directional trends of the values;

pressure-based threshold values as proxies.