Your Guide to Air Quality

Blog post written by Ilana Williams, Montgomery County 2023 Summer Climate Intern

At the beginning of June, Maryland issued a Code Red air quality alert in response to the smoke from the wildfires in Eastern Canada, according to a statement from Governor Wes Moore. The Maryland Department of Health advised everyone to limit outdoor activities.

Poor air quality leads to increased asthma and heart attacks, throat irritation and shortness of breath. More than 60,000 adults in Montgomery County have asthma, according to the Maryland Asthma Control Program. People who live in the Washington, D.C. region are at risk from unhealthy ground-level ozone during the summer because it impacts people’s health and warms the climate.

In January, the EPA announced a proposal to strengthen air quality standards for PM_2.5 to protect communities from fine particles emitted from construction sites, unpaved roads, and fires, according to a press release from the EPA. The proposal with strengthen health-based standards from a level of 12 micrograms per cubic meter to between nine and ten micrograms per cubic meter.

The National Oceanic and Atmospheric Administration monitored more than 400 fires burning across Canada in the beginning of June.  The smoke from the fires spread to the U.S. reaching as far as South Carolina.

The DMV region is typically in Code Green or Code Yellow for air quality. Then on days like, Fourth of July the air quality is worse because of the fireworks. However, the smoke traveling from Canada was the first time the Metropolitan Washington Council of Governments issued a Code Purple on the Air Quality Index for the DMV region, according to Jen Desimone, the air program chief at the COG and the managing director for Clean Air Partners.

The Air Quality Index is divided into six categories that correspond to different health concerns. The AQI reports daily air quality and uses color codes and a numerical scale to report how clean or polluted the air is and what associated health effects be of concern. Purple Code represents the air quality as very unhealthy with a value between 201 to 300. With a Purple alert, the risk of health effects is increased for everyone.

Particle pollution (PM) is measured by looking at PM_2.5 and PM­₁₀. PM­_2.5 is smaller than the diameter of a piece of hair, which makes them dangerous when someone breathes them in, Desimone said. PM_2.5 is not filtered in the nasal passage and can travel through people’s respiratory system.

“Anybody that has respiratory problems (and) heart conditions need to be really careful,” Desimone said. “If (the air) gets really bad, limit your exposure completely.”

Since 1999 the air quality has improved in the metropolitan Washington region. For instance, in 2001, there were 25 days of Code Orange, according to a chart from COG that shows number of days under the PM­_2.5 standard. In 2023, there has been one day of Code Orange and two days of Code Red.

COG monitors track air pollution in the DMV region with help from the Maryland Department of the Environment, the District Department of Energy and Environment and the Virginia Department of Environmental Quality. The data gets shared with the Environmental Protection Agency.

“(Air quality) is a regional issue that everybody needs to think about,” Desimone said. “The air that you’re breathing comes from somewhere else. So, the entire region really does need to work together.”