Division 2.9.1 Emissions to water United Kingdom Original text. Later amendments are not shown. BAT 43BAT is to monitor pollutants in waste water and potentially contaminated surface run-off water prior to each batch discharge in accordance with EN standards. If EN standards are not available, BAT is to use ISO, national or other international standards that ensure the provision of data of an equivalent scientific quality. ← Division 2.9 Division 2.9.1 Division BAT 43 →