Levels of ozone pollution spurred by warm, sunny weather are expected to climb through today, leading to the first ozone alert of the season for Denver and the Front Range.
The state health department has issued the alert through 4 p.m. today.
“This is just to notify people – people who may have health issues – that ozone levels may climb,” said Christopher Dann, a spokesman for the state air pollution control division.
The alert also urges motorists to refuel cars and home owners to mow lawns in the evenings.
Ozone, which is a prime ingredient in smog, is an acrid gas formed when volatile compounds, from auto tailpipes, power plants and other sources, interact with light and heat. High ozone levels can impair breathing and exacerbate asthma and other respiratory ailments. They also can affect healthy people who work or exercise outdoors and can cause breathing difficulties and eye irritations.
“This isn’t surprising,” Dann said. “Last year 49 alerts were issued, with more than 20 in June.”
Federal clean-air regulations deem ozone levels above an average of 85 parts per billion to be unhealthy. The state issues an alert any time it believes levels will reach 75 parts per billion, Dann said.
This is a crucial ozone season for the Denver region. After two summers of exceeding federal health standards, the Front Range must meet ozone targets this year or run afoul of the Clean Air Act.
Not meeting clean-air standards could lead to federal sanctions, such as restrictions on highway projects and industry expansions.
The federal Environmental Protection Agency is proposing a tighter standard of 60 parts per billion.
Staff writer Mark Jaffe can be reached at 303-954-1912 or mjaffe@denverpost.com.
