Ambient air quality standards are variable in Asian countries. In many cases they lag behind international developments in AQ standards designed to protect human health and the environment. As new scientific information becomes available, WHO, EU, and some countries amend their AQ standards or guidelines on a regular basis to protect human health. For example, as new knowledge about the dose-response relationship between particulate and human health have become available, new standards such as standards for PM2.5 and amendments to existing standards (such as for PM10) have been introduced. Most Asian nations have not kept pace with these developments. Most do not have AQ standards for PM2.5, and have standards for PM10 that are outdated and do not provide an adequate margin of protection for human health according to current scientific knowledge

WHO has recently updated the ambient AQ guidelines to protect human health. Although the new standards are more stringent, WHO has also proposed interim targets (3 steps) for PM10, PM2.5, SO2 and Ozone. These can be useful for policy makers in Asian countries as they provide attainable interim targets for actions to reduce pollutant concentrations in urban air.

CAI-Asia has been compiling the legislated ambient AQ standards of countries (and cities whenever available) and checks how they fare with WHO guidelines as well as standards implemented in Europe and USA.

Ozone Standards in Asia [.pdf, 18.2Kb]

PM Standards in Asia [.pdf, 19.4Kb]