Ambient air quality standards in China

China recently announced ambient air quality standards. This article describes the standards and compares them with standards that exist in the Federal Republic of Germany, Japan, and the United States. An unusual feature of the Chinese standards is the establishment of different classes of standards, applicable in different types of areas. The present status of air pollution in several Chinese cities is examined. Data on the levels of suspended particulates, sulfur dioxide, and carbon monoxide in several Chinese cities are presented. Some of the difficulties involved in implementing the new standards are discussed.Work undertaken while at the Environment and Policy Institute, East-West Center, and School of Public Health, University of Hawaii, Manoa, Honolulu, HI 96822, USA.