Setting of threshold values through Union, regional or subregional cooperation
Article 4
1. Where Member States are required under this Decision to establish threshold values through Union, regional or subregional cooperation, those values shall: (a) be part of the set of characteristics used by Member States in their determination of good environmental status; (b) be consistent with Union legislation; (c) 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; (d) be set at appropriate geographic scales of assessment to reflect the different biotic and abiotic characteristics of the regions, subregions and subdivisions; (e) be set on the basis of the precautionary principle, reflecting the potential risks to the marine environment; (f) be consistent across different criteria when they relate to the same ecosystem element; (g) make use of best available science; (h) be based on long time-series data, where available, to help determine the most appropriate value; (i) 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; (j) be consistent, where practical and appropriate, with relevant values set under regional institutional cooperation structures, including those agreed in the Regional Sea Conventions. 2. Until Member States have established threshold values through Union, regional or subregional cooperation as required under this Decision, they may use any of the following to express the extent to which good environmental status is being achieved: (a) national threshold values, provided the obligation of regional cooperation laid down in Articles 5 and 6 of Directive 2008/56/EC is complied with; (b) directional trends of the values; (c) pressure-based threshold values as proxies. These shall follow, where possible, the principles set out in points (a) to (i) of paragraph 1. 3. Where threshold values, including those established by Member States in accordance with this Decision, are not met for a particular criterion to the extent which that Member State has determined as constituting good environmental status in accordance with Article 9(1) of Directive 2008/56/EC, Member States shall consider, as appropriate, whether measures should be taken under Article 13 of that Directive or whether further research or investigation should be carried out. 4. Threshold values established by Member States in accordance with this Decision may be periodically reviewed in the light of scientific and technical progress and amended, where necessary, in time for the reviews provided for in Article 17(2)(a) of Directive 2008/56/EC.