You may have heard of Knozone Action Days in Central Indiana, but you might be less familiar with what exactly ozone is or what you’re supposed to do when it hits peak levels. Here are the basics.
Ozone is a gas created when certain VOCs (volatile organic compounds) react chemically with NOx (nitrogen oxides) in the presence of intense sunlight. That’s why ozone levels spike in the summer months when it’s sunny and hot.
Ozone is most often associated with the ozone level in the stratosphere - where it shields the Earth below from harmful UV radiation. When it hovers over close to the ground as smog, however, ozone is harmful to human health and natural ecosystems.
PM2.5 - or particulate matter - is another unit of measure we talk about often. It refers to tiny solid particles or liquid droplets found in the air, including common pollutants such as soot, smoke, dust, and dirt, as well as chemical compounds like sulfates and nitrates. Your body is remarkably good at cleaning the air you inhale before it reaches your lungs and bloodstream. PM2.5 particles, though, are so small - you could fit 40 or more across the width of a single strand of hair - that they can sneak past the body’s defenses and damage health over time.
Knozone Action Days are declared when factors likely to produce high levels of ozone and PM2.5 align - high temperatures, sunny skies, little wind, etc. On these days, air quality can be unhealthy for Indianapolis and Central Indiana residents. Everyone should look to reduce their outdoor activity - especially strenuous exercise - on Action Days, but certain groups may be more affected than others. These include:
Fortunately, there are many ways to help combat high levels of ozone and air pollution:
Of course, protecting air quality isn’t only important on Knozone Action Days. There are things you can do every day of the year to help clean up Central Indiana’s air. Check out our How You Can Help section for ways to get started.