The standard was formulated for the purpose of implementing the Environmental Protection Law of the People's Republic of China, Law of the People's Republic of China on Prevention and Control of Water Pollution, Marine Environmental Protection Law of the People's Republic of China, Air pollution Prevention and Control Law, and the Law of People's Republic of China on Prevention and Control of Pollution by Solid Wastes. It also serves the purpose of promoting the construction and management of municipal waste water treatment plants, strengthening control and reuse of pollutants and protecting human health and environment. Reference was made to the Technical Policy of Municipal Sewage Treatment and Pollution Prevention while drafting the standard. The standard provides control indices and standard for pollutants from outflow, waste gas and sludge for different time period. Municipal wastewater treatment plants shall be subject to the standard upon when it comes into force. Industrial wastewater and wastewater from medical institutes shall meet the national industrial standard, local discharge standard and local requirement for total discharge. The standard also applies to residential communities and industrial companies for their management of pollutants discharged from domestic sewage treatment facilities. The standard is the first of its kind.

Discharge  standard of pollutants for municipal wastewater treatment plant (GB 18918-2002)