Illinois EPA announces early start to 2017 Ozone Season

Ozone Season Begins March 1

SPRINGFIELD — Illinois Environmental Protection Agency (Illinois EPA) Director Alec Messina has announced the early start to the 2017 Ozone Season. This is the time of year where meteorology and air pollution could result in elevated ground-level ozone. Previously, the ozone season ran from April through October, and 2017 is expanding by one month at the direction of U.S. EPA.

In 2015, U.S. EPA strengthened the national ambient air quality standard for ground-level ozone. Following the implementation of the new standard in 2016, U.S. EPA updated the Air Quality Index and subsequently updated the ozone monitoring seasons in 32 states, including Illinois. The extra month of monitoring will standardize the ozone season across a number of states.

“The earlier start to the ozone season offers an important reminder to residents to check their daily air quality forecasts,” said Director Messina. “Illinois EPA issues the forecasts to provide residents with important information to protect their health and take special precautions. Residents should check their daily air quality just like they check the daily weather.”

States use the Air Quality Index (AQI) to forecast each day’s air quality according to the six-colored system ranging from “Good” (Green) to “Hazardous” (Maroon). Historically, Illinois has not reached the top two categories of “Very Unhealthy” or “Hazardous.”

Ground-level ozone is formed through a complex chemical reaction with air pollution and sunlight. Emissions from vehicles and industry are heated up by the sunlight to form ground-level ozone. Elevated ozone levels can impact individuals, especially seniors, children and those with respiratory and heart conditions. Those individuals should take special precautions and follow their physician prescribed regimen when ozone levels are elevated.

The Illinois EPA provides the daily air quality forecast at https://www.airnow.gov. Residents can also receive free air quality forecasts via email or text by registering at http://illinois.enviroflash.info. The Agency also posts daily air quality forecasts for five regions on Twitter @IL_AirQuality. Air quality information for the Chicago Metropolitan area is provided in partnership with Illinois Partners for Clean Air at www.cleantheair.org and @IL_PFCA.

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