Particle Pollution and Health

Particle pollution from fine particulates (PM2.5) is a concern when levels in air are unhealthy. Breathing in unhealthy levels of PM2.5 can increase the risk of health problems like heart diseaseasthma, and low birth weight. Unhealthy levels can also reduce visibility and cause the air to appear hazy.

Particle pollution can come from outdoor and indoor sources.

  • Outdoor sources include vehicle exhaust, burning wood, gas and other fuels, and fires. Particle pollution can also travel long distances from its source; for example from wildfires hundreds of miles away. Outdoor particle pollution levels are more likely to be higher on days with little or no wind or air mixing.
  • Common indoor sources are tobacco smoke, broiling or frying food, burning candles or oil lamps, fireplaces, and fuel-burning space heaters.

When Outdoor Air is Unhealthy

  • Spend more time indoors. This is especially important for at-risk groups (“sensitive groups”), like children and teenagers, older adults, people with heart or respiratory problems, pregnant people, and those who exercise or work outdoors.
  • If it gets hot inside, cool off with air conditioning if you can. Find a place to get cool.
  • People who must spend time outdoors should consider wearing a mask (use the best well-fitting face mask you have on hand. A N95 or KN95 will work best), take frequent breaks, and adjust work or exercise schedules for when air conditions improve.
  • Schools, child and adult care facilities, employers and activities programs should plan for more indoor activities or reduce outdoor activities when air quality is unhealthy.
  • People with health symptoms should contact their health care provider.
  • Get the latest air quality conditions by visiting DEC's air quality forecast website or

Follow Air Quality Alerts

New York State alerts the public when particle pollution is expected to be unhealthy. An Air Quality Alert is issued the day before or on the same day for the region of the state that is affected. These alerts are often broadcast on the news or weather station.

AQI Basics for Particle Pollution
Air Quality Index Who is at risk? What to do?
Green: 0 to 50 Good Air quality is good. It's a great day to be outside.
Yellow: 51 to 100 Moderate People unusually sensitive to air pollution. Air quality is acceptable. Consider making outdoor activities shorter and less intense. If you are coughing or have shortness of breath take it easier.
Everyone else: It's a good day to be active outside.
Orange: 101 to 150 Unhealthy for Sensitive Groups Sensitive (at-risk) group: people with heart or lung disease, older adults, children and teens, pregnant people, and those who exercise or work outdoors. Sensitive group: Make outdoor activities shorter and less intense. Take more breaks. Keep medicine handy.
Everyone else is less likely to be affected.
Red: 151 to 200 Unhealthy Everyone Sensitive group: Avoid long or intense outdoor activities. Consider rescheduling or moving activities indoors.
Everyone else: Reduce long or intense outdoor activities. Take more breaks.
Purple: 201 to 300 Very Unhealthy Everyone: Health Alert Sensitive groups: Avoid all physical activity outdoors. Reschedule or move activities indoors.
Everyone else: Avoid long or intense outdoor activities. Consider rescheduling or moving activities indoors.
Maroon: 301-500 Hazardous Everyone: Health Warning Everyone: Avoid all outdoor physical activities.
Sensitive groups: Keep activity levels low at home.

Contact a health care provider if you have symptoms like shortness of breath, heart palpitations, or unusual fatigue.

Filtering Air at Home

  • If you have one, consider using an air cleaner. This can greatly reduce indoor air particle levels.
  • Window or portable air conditioners are good to use if they recirculate air (check your user’s manual).
  • You can run stand-alone fans to recirculate air in the home, but avoid using whole house fans because they draw in air from outside.
  • If you have a central air conditioning and heating system, set the system to “on” so air is constantly filtered, rather than “auto,” which intermittently runs the system.
  • Consider installing a high-efficiency filter (MERV 13 rating or higher) if your system can handle it based on the manufacturer’s recommendation.
  • When outdoor air quality is good, you can open windows and doors and use fans to bring in fresh air.

Recommendations for Workers

  • Long schedules and the physical demands of outdoor work can affect health when air quality is unhealthy.
  • Take frequent breaks and talk to your employer about adjusting your work until air quality improves. Follow advice from NIOSH.

Recommendations for Schools and Child Care Providers

  • Continue to monitor air quality at DEC's air quality forecast website or
  • Consider implementing an Air Quality Flag Program where your organization raises a flag for the day when the air is unhealthy. On these days you can use this information to adjust outdoor activities.
  • New York State recommends that schools and child care providers suspend outdoor activities and field trips when air quality is unhealthy.
  • Children who spend time outdoors should wear a well-fitting face mask.
  • When air quality is good, you can resume normal activities; masking is not necessary.

More About Health Risks

The term fine particles, or particulate matter 2.5 (PM2.5), refers to tiny particles or droplets in the air that are 2 ½ microns or less in width. The largest PM2.5 particles are about 30-times smaller than a human hair. The smaller particles are so small that several thousand of them could fit on the period at the end of this sentence.

Fine particles in the air (measured as PM2.5) are so small that they can travel deeply into the respiratory tract, reaching the lungs, causing short-term health effects such as eye, nose, throat and lung irritation, coughing, sneezing, runny nose, and shortness of breath. Exposure can also affect heart and lung function, worsening medical conditions like heart disease and asthma, and increase the risk for heart attacks. Scientific studies have linked increases in daily PM2.5 exposure with higher cardiovascular and respiratory hospital admissions, emergency department visits, and deaths. Studies also suggest that long-term exposure to fine particles causes increased mortality from heart disease and may be associated with increased rates of chronic bronchitis, reduced lung function, and lung cancer. People with heart and breathing problems, pregnant women, children, and older adults may be particularly sensitive to particle pollution.

The New York State Departments of Health and Environmental Conservation (DEC) alert the public when particle pollution levels in outdoor air are expected to be unhealthy. An air quality health advisory is issued for the next day or on the same day for a specific region when concentrations at one or more monitoring stations in that region are predicted to be elevated. DEC staff review particle pollution monitoring data and weather conditions to determine if an air quality health advisory is warranted. There could be a few days each year when the monitoring data, meteorology and computer modeling fail to correctly predict the need for an advisory.

Yes. Environmental Protection Agency (EPA) established National Ambient Air Quality Standards for PM2.5. National Ambient Air Standards are established to be protective of public health. The short-term standard (24-hour or daily average) is 35 micrograms per cubic meter of air (µg/m3) and the long-term standard (annual average) is 9 µg/m3.

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