UKTAG has developed methodologies for assessing the condition of the biological quality elements and these are set out in the UKTAG method statements below. These biological assessment methods are final except where stated. The method statements listed below explain the sampling and analysis involved and indicate how to calculate the ecological quality ratio for each classification tool. The class boundary standards are not found in these documents. These have been published by Ministers and links to these documents can be found below. 

Scotland River Basin District (Surface Water Typology, Environmental Standards, Conditions Limits and Groundwater Threshold Values) Directions 2009

http://www.scotland.gov.uk/Publications/2010/01/06141049/1

The Solway Tweed (Scotland) River Basin District (Surface Water Typology, Environmental Standards, Conditions Limits and Groundwater Threshold Values) Directions 2009

http://www.scotland.gov.uk/Publications/2009/12/14130958/0

England and Wales River Basin District (Surface Water Typology, Environmental Standards, Conditions Limits and Groundwater Threshold Values) Directions 2009

http://www.defra.gov.uk/environment/quality/water/wfd/documents/river-basin-typology-standards.pdf