What is Particulate Matter?
Particle pollution is a mixture of microscopic solids and liquid droplets suspended in air. This pollution, also known as particulate matter, is made up of a number of components, including acids (such as nitrates and sulfates), organic chemicals, metals, soil or dust particles, and allergens (such as fragments of pollen or mold spores). Unlike summertime ozone, particle pollution can occur year-round, and is linked to serious health problems, even at concentrations found in many cities.
Particles come in a wide range of sizes. Fine particles are less than 2.5 micrometers in diameter. How small is that? About 1/30th the diameter of the average human hair – so small, you’d need an electron microscope to see them.
Some fine particles can be emitted directly (think of smoke from a woodstove). But most are formed secondarily from complex atmospheric reactions of gases such as NOx and sulfur dioxide (SO2) that are emitted from power plants, industries, cars, buses and trucks.
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What is the current National Ambient Air Quality Standard for PM2.5?
The Current NAAQS for PM 2.5 is 15 ug/m3 annually, and 35 ug/m3 daily.
Where can I get regional information on Particulate Matter Pollution?
For information on PM2.5 levels in the region and to learn when PM2.5 can be harmful visit Clean Air Partners which provides real time measurements from regional air quality monitors.
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What Can You Do To Reduce Particulate Matter Pollution?
All of the measures you can take to reduce ozone pollution will also reduce the emissions of PM 2.5 and precursor chemicals. In addition,
- Reduce or eliminate fireplace and wood stove use
- Avoid using gas-powered lawn and garden equipment
- Avoid burning leaves, trash and other materials
- Use household, workshop, and garden chemicals in ways that keep evaporation to a minimum, or try to delay using them when poor air quality is forecast.
- Replace your car's air filter and oil regularly
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