Guidelines for drinking-water quality

This 4th edition of the Guidelines further develops concepts, approaches and information introduced in previous editions, including the comprehensive preventive risk management approach for ensuring drinking-water quality that was introduced in the third edition. It considers:
drinking-water safety, including
 • minimum procedures and specific guideline values and how these are intended to be used;
• approaches used in deriving the Guidelines, including guideline values;
• microbial hazards, which continue to be the primary concern in both developing and developed countries;
• climate change;
• chemical contaminants in drinking-water, including information on chemicals
not considered previously;
• those key chemicals responsible for large-scale health effects through drinking water
exposure;
• the important roles of many different stakeholders in ensuring drinking-water
safety;
• guidance in situations other than traditional community supplies or managed
utilities, such as rainwater harvesting and other non-piped supplies or dual piped
systems.