PM2.5 and PM0.3

PIW Environmental  /  Particles  /  PM2.5 and PM0.3

PM2.5 and PM0.3

What is fine particulate matter?

Particulate matter is characterized according to size - mainly because of the different health effects associated with particles of different diameters. Particulate matter is the general term used for a mixture of solid particles and liquid droplets in the air. It includes aerosols, smoke, fumes, dust, ash and pollen. The composition of particulate matter varies with place, season and weather conditions. Fine particulate matter is particulate matter that is 2.5 microns in diameter and less. It is also known as PM2.5 or respirable particles because it penetrates the respiratory system further than larger particles. PM2.5 in Texas is largely made up of sulphate and nitrate particles, elemental and organic carbon and soil

What are the sources of fine particulate matter?

PM2.5 material is primarily formed from chemical reactions in the atmosphere and through fuel combustion (e.g., motor vehicles, power generation, industrial facilities, residential fire places, wood stoves and agricultural burning). 

Texas Fine Particulate Matter Emissions by Sector - 2012 Estimates

Chart: Ontario Fine Particulate Matter Emissions by Sector - 2012


Texas Fine Particulate Matter Emissions by Sector - 2012 Estimates
Category Percent
Residential 39%
Other Transportation 19%
Other PM2.5 Industrial Processes 15%
Smelters/Primary Metals 11%
Miscellaneous 8%
Cement and Concrete Industry 5%
Road Vehicles 3%

Note: 2012 is the latest complete inventory. Emissions may be revised with updated source/sector information or emission estimation methodologies as they become available.

Approximately 39% and 22% of PM2.5 emitted in Texas in 2012 came from residential and transportation sectors, respectively, while other PM2.5 industrial processes accounted for 15%. Lesser sources of PM2.5 include smelters/primary metals, miscellaneous, and cement and concrete industry.