Skip to main content

Particulate Matter (PM10 and PM2.5) Pollution

Particulate matter, sometimes referred to as particle pollution or PM, is a complex mix of very small particles, water vapor, and gases. Common small particles can include lead, dust, dirt, and sand. When these components combine, air pollution forms.

EPA regulates two categories of particulate matter for health and welfare reasons:

  • PM10: “Inhalable coarse particles” are between 2.5 and 10 micrometers in diameter
  • PM2.5: “Fine particles” are smaller than 2.5 micrometers in diameter 

For a size comparison, a single strand of human hair on average is 70 micrometers in diameter, making it 30 times larger than the largest fine particle.

Keep in mind, particle pollution can come from many different types of particles, gasses, and liquids. Particle pollution can be sourced from construction sites, unpaved roads, fields, smokestacks, and fires. But they can also come from atmospheric reactions between gasses like sulfur dioxides and nitrogen oxides that are emitted from power plants, other industries, and cars.

Health and Welfare Effects

These fine particles pose more health risks than larger particles like gravel because they can settle deeper into the lungs and even into the bloodstream. Like other air pollution, particles can cause premature death in people with heart or lung disease, nonfatal heart attacks, irregular heartbeat, aggravated asthma, decreased lung function, and respiratory issues like inflamed airways and difficulty breathing.

Particulate Matter Plans

Arizona has a unique mix of urban and agricultural sources of particulate matter. Several areas of the state have historically exceeded the PM10 and PM2.5 air quality standards. See our e-Map for the Particulate Matter (PM) nonattainment and maintenance areas | View e-Map > 

Gila County

2012 Limited Maintenance Plan Update for Payson PM10 Maintenance Area | Download >

Maricopa County

2012 Maricopa Association of Government Five Percent Plan for PM10 for Maricopa County Nonattainment Area | Download >

Mohave County

2012 Limited Maintenance Plan Update for Bullhead City PM10  Nonattainment Area | Download >

Pinal County

2012 Five Percent Plan for PM10 for Pinal County Township 1 North, Range 8 East Nonattainment Area | Download >
2015 West Pinal Moderate PM10  Nonattainment Area Plan | Download >

Pima County

2008 Rillito Moderate Area PM10 Limited Maintenance Plan and Request for Redesignation | Download >

2019 Ajo PM10 Redesignation Request and Maintenance Plan | Download > 

Santa Cruz County

2012 Nogales PM10  Nonattainment Area Plan | Download >
2013 Nogales PM2.5  Nonattainment Area Plan | Download >

Yuma County

2006 Yuma PM10 Maintenance Plan | Download >