1) This indicator is one of the most frequent indicators used in the emergency context for assessing water quality. Water supply interventions operating in the development context frequently use a range of other biological, chemical and physical aspects of drinking water quality required by the national standards or recommended by WHO's international Guidelines for Drinking Water Quality (see below). If you operate in a development context, consult your WASH advisor and local authorities to identify the most relevant standards and adjust this indicator accordingly.
2) Both in the development and emergency context, it is equally important to assess whether regular water quality controls take place and whether the controls' findings are used for improving the water quality.