Behind the Jargon: Air Quality Alerts Simplified

Woman Jogging on Boardwalk

By Kasia Broussalian

In this photo, a woman runs along the piers of the Hudson River Park on a morning with several air quality alerts for the metro area. A brownish haze illuminates the buildings of downtown Jersey City across the river. It seems like every few days this summer, New Yorkers receive a little warning with their morning weather updates; an air quality alert warning. Having lived most of my life near the beautiful mountains in Colorado (yes, the air really is crisp there. I can see why 19th century doctors believed the place could cure tuberculosis), an air quality alert is anything but clear to me. Scrolling down the alert message, I am told to be aware of high ozone and particle matter levels, especially if I am in a high risk group. First of all, is the ozone layer down at my level? Uh hem, Kohl Elementary School, you taught me that the ozone layer was in the stratosphere above me. Did you lead me astray? Second, what are these particles?! That’s very vague. Third, what constitutes a high risk group? But, rest assured fellow New Yorkers equally confused as me, I have done some research.

Ground Level Ozone: There is ozone down at my level. Ozone, which is comprised of three oxygen atoms, is created by a chemical reaction between oxides of nitrogen and volatile organic compounds in the presence of sunlight. Though the chemical makeup is the same at ground level as it is in the atmosphere, this ozone is labeled as “bad.” New fact of the day: ground-level ozone is a bit classier way of saying “smog.”

Particle Matter/Particle Pollution: It’s a bit vague… “particle pollution is a complex mixture of extremely small particles and liquid droplets.” It gets a bit better. These particles include “acids such as nitrates and sulfates, organic chemicals, metals, and soil or dust.” EPA is particularly concerned with particles that are smaller than 10 micrometers, because they can seep deep into our lungs and stay there. Even worse, more is at stake than our personal health. Particle pollution is responsible for visibility impairment such as haze, contributes to acid rain fall out in our rivers and lakes, and can damage and stain stone and other architectural materials.

High Risk Group/ Sensitive Group/Code Orange: I particularly like that last one; code orange. It sounds fairly alarming. A day labeled as code orange means that air pollution levels are unhealthy for those in sensitive groups. Sensitive groups include young children, the elderly, those suffering from heart and lung disease or asthma, or those planning on strenuous outdoor activity.

Check out more about air quality and pollution on EPA’s Web site.

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