Evolution of PM2.5 Measurements and Standards in the U.S

National Ambient Air Quality Standards (NAAQS) were first established in the United States to protect public health and welfare, and the concept has been adopted in China and many other countries.

For particulate matter (PM), the NAAQS indicator evolved from total particle mass concentration, to PM10 and PM2.5 mass concentrations as defined by the PM size-selective properties of the monitoring instrument and human inhalation characteristics.

The objectives of this paper are to:

  • provide a brief summary of the evolution of size-specific fractions for suspended particulate matter (PM)
  • review relationships between inhalation properties and their health effects
  • illustrate changes in PM measurement methods and air quality standards; and
  • look to the future of multipollutant air quality management.

This interesting article may be downloaded here:-

Evolution of PM2.5 article