Chesterton Tribune



Watch for IDEM air quality action days this summer; cut down on emissions

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Summer officially begins on June 21--the longest day of the year--and the Indiana Department of Environmental Management (IDEM) wants to remind Hoosiers that longer days mean more energy from the sun beating down on the state.

“That energy from sunlight mixes with emissions from vehicles and industrial plants, producing ozone in our lower atmosphere,” IDEM says. “While ozone high in the stratosphere protects us from the sun’s harmful ultra-violet (UV) rays, when ozone is created down where we live, it can make breathing difficult for some people.”

As weather forecasts point to conditions favorable for the accumulation of this ozone, IDEM will issue “air quality action days” over the course of the summer.

An air quality action day is declared when IDEM’s meteorologists have looked at weather patterns, cloud forecasts, and other data to determine that a certain period of time will likely see higher ozone levels than normal for a particular area.

Whenever there is an air quality action day for your area, doing the following will reduce the chance that the air you breathe will become unhealthy.

* Drive only when necessary. Fewer vehicle emissions in the air mean fewer compounds that can turn into ozone when the sun’s heat bakes down on them. Instead of driving. So walk, ride your bike, or just lounge around at home. If you have to work that day, take the bus in or carpool. If you live close to your job, think about walking or biking to work. That way you can stay healthy, while reducing air pollution.

* Fuel your vehicle after 7 p.m. When you gas up your car, vapors that escape can react with the sun to produce ozone. After 7 p.m., there is less energy in the atmosphere to create this reaction.

* Mow your lawn after 7 p.m. as well. Even though your lawn mower’s motor is likely smaller than your car’s, it has a less sophisticated emissions control system, so it probably pollutes more than a modern automobile does.

* Don’t idle your vehicle. Instead of using the drive-through lane, park your car and go inside to pick up your food.

Air quality action days are also called if fine particulate matter (PM 2.5) is at levels that can interfere with some people’s health. These tiny particles are the result of vehicle emissions, burning coal or wood, and some industrial processes. PM 2.5 refers to the size of the particles which are 2.5 microns in width or smaller. These particles create a hazy, foggy cloud over an area.

Like ozone, the prevalence of PM 2.5 is closely tied to the weather forecast. IDEM meteorologists look especially at wind patterns and temperature changes to determine if PM 2.5 levels are likely to be high for a certain day. Hot days with stagnant air are more likely to become air quality action days. The same methods of preventing ozone help to prevent an increase of PM 2.5 in the air as well.

SmogWatch is an informational online tool created by IDEM to share air quality forecasts for each day. It provides daily information about ground-level ozone and particulate matter air quality forecasts, health information, and monitoring data for seven regions of Indiana. You can find it at

More information on how to reduce ozone can be found at



Posted 6/5/2013