Air Pollutants

Air Pollutants in Spokane
Of the six criteria pollutants, two are of particular concern in Spokane: Ozone (a summertime pollutant) and Particulate Matter.

In addition to the criteria pollutants, there is a category of pollutants that fall under the Air Toxics rules. Click here for more information.

Ozone	Particulate Matter PM10	Particulate Matter PM2.5

Ozone (O3) Unlike ozone that is present in the Earth’s upper atmosphere, ozone at the Earth’s surface is a harmful air pollutant that poses a risk to human, animal and plant life.

• Ground-level ozone (a key ingredient of smog) is formed as a result of chemical reactions between nitrogen oxides and volatile organic compounds in the presence of sunlight and heat. Most of the ozone-forming emissions come from many small sources, spread over a wide area. Click here to see a short video on how ozone is formed.

Nearly two-thirds of these emissions come from motor vehicles. Other sources of smog-forming emissions include industrial solvents, gasoline refueling, gasoline-powered yard equipment, auto body paint shops, and consumer products such as charcoal lighter fluid, paints, etc.

Even at low concentrations, ozone causes respiratory problems and aggravates asthma in children, people with respiratory diseases, and even otherwise healthy adults who are working or exercising outside on smoggy days. Children are most at risk from exposure to ozone because they are often active outside during the summer and their lungs are not fully developed. Long-term exposure to ozone may lead to premature aging of the lungs and chronic respiratory illnesses.  For information about ozone, click here.

Particulate Matter (PM) is composed of solid or liquid particles from smoke, dust, and condensing vapors. PM is suspended and carried in the air for long periods of time and over long distances. There are health-based standards for two sizes of particles (PM10 and PM2.5). These microscopic particles travel deep in the lungs, damaging lung tissue and affecting breathing.

• Spokane’s PM pollution comes from a variety of sources, including dust stirred up from traveling on unpaved and paved roadways, construction activities, gas and diesel powered engines, wood burning, outdoor burning and industrial/commercial operations.

Carbon Monoxide (CO) is an odorless, colorless gas which is emitted from any form of combustion. When inhaled, CO deprives the body of oxygen by reducing the blood’s capacity to carry oxygen. This can lead to headaches, dizziness, nausea, and at high levels can be lethal.

• Motor vehicles are the largest contributor to CO, and other sources include industrial and commercial operations, wood stoves and fireplaces, and outdoor burning.
  
• CO is generally considered a wintertime pollutant, with its highest levels occurring on cold, stagnant winter days. Spokane’s CO levels have been on the decline over the past couple of decades and for several years in a row we've met all health-based standards established for carbon monoxide.

You can help clear the air! Click here for information.