2.5 Monitoring - NYS Dept. of Environmental Conservation

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PM2.5 Monitoring

Fine Particulate Matter Monitoring

Picture depicts relative sizes of different types of particulate matter as they relate to the size of a human hair

PM is an abbreviation for particulate matter. PM2.5 is the abbreviation for fine particulate matter with a diameter smaller than 2.5 microns. (By comparison, human hair diameters range from 40 to 120 microns.) Particulate matter are tiny particles or droplets in air. The size of particulate matter is so small, it is hard to imagine.

The picture to the left shows a human hair that has been magnified 900 to 1200 times its real size. The blue circles show how small PM10 is when compared to a human hair. The smaller orange circles inside the blue circle shows how much smaller PM2.5 particles are against a human hair. The green circles inside the orange circle show how even smaller ultrafine particles are in comparison to a human hair.

Sources of PM2.5

PM2.5 is produced by:

  • Burning petroleum-based fuels for heating buildings and powering motor vehicles
  • Chemical reactions between gases such as sulfur dioxide, nitrogen oxides, and volatile organic compounds
  • Dust from industrial activities
  • Residential wood burning, forest fires, and agricultural burning

The total amount of PM2.5 observed or forecasted for a given area forms from a combination of local and upwind sources. The emission of sulfur dioxide or other pollutants can be emitted in one region and undergo chemical reactions in the atmosphere to produce PM2.5 in another region downwind. Similarly, PM2.5 can itself travel great distances. It has been observed that large wildfires from the western part of North America have occasionally impacted air quality monitors in New York.

Health Effects of PM2.5

Adverse health effects from breathing air with a high PM2.5 concentration include:

Division of Air Resources staff performing regular maintenance on the air quality monitoring equipment located at the Queens College air monitoring site.
Division of Air Resources staff Mike Christophersen
performing regular maintenance on the air quality
monitoring equipment located at the Queens College
air monitoring site.

  • Increased respiratory symptoms and disease
  • Chronic bronchitis
  • Decreased lung function, particularly for individuals with asthma
  • Irregular heartbeat
  • Premature death in people with heart or lung disease

Monitoring PM2.5

The EPA has promulgated health-based standards for the concentration of PM2.5 in the outdoors. The National Ambient Air Quality Standards (NAAQS) for the 24-hour average and annual average have been set at 35 and 12 micrograms (one-millionth of a gram) per cubic meter air (µg/m3), respectively. A microgram is a unit of weight. There are a million micrograms in a gram, and a pound is equal to about 450 grams. These measurements are gathered using EPA's Federal Reference Method (FRM). The PM2.5 FRM is a filter-based method whereby one 24-hour sample is collected every sixth day, except for a few sites where a sample is taken every third day. Only FRM data will be used for determining compliance with the health-based standards.

There are also air quality monitors using this technology, modified to collect PM10 samples. PM10 is the abbreviation for fine particulate matter with a diameter smaller than 10 microns. PM10 samples from the Rochester and IS 52 Bronx sites are further analyzed to determine concentrations of selected metals. DEC also complements the FRM network with real-time, direct reading, hourly PM2.5 measurements that can be found on the Current Air Quality Measurement Data web page.

More information about PM2.5 and PM10 is available in the New York State Ambient Air Monitoring Program Monitoring Network Plan.

PM2.5 Monitoring Sites

Map showing Ambient Air Monitoring stations for PM2.5