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  • Ozone Air Pollution Season On Its Way

    May 18, 2015 | Read More News
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    Hot and stagnant summer air provides the perfect conditions for the creation of an air pollutant called ground-level ozone. Miles above us in the naturally occurring layer, ozone acts as a protective shield against damaging solar radiation. But at ground level, ozone irritates respiratory system tissue and can damage the lining of the lungs, causing a reaction similar to sunburn. Ozone aggravates asthma, emphysema and other respiratory diseases.Human Respiratory System

    “We have sun pretty much all year in Pima County, but it is that intense summer sun combined with motionless air and long hours of daylight that increase the amount of ozone pollution,” said Beth Gorman, Pima County Department of Environmental Quality Senior Program Manager.  In the presence of strong summertime solar radiation and slow-moving high pressure systems, emissions from motor vehicle tailpipes, fossil fuel power plants and other sources react with fumes from gasoline, industrial processes, paints, lighter fluid and solvents to form ground-level ozone. 

    Over the last three years, the eight ozone-monitoring stations operated by PDEQ have reported ozone levels at more than 90 percent of the U.S. Environmental Protection Agency’s Air Quality Standard on several days each summer.

    “Exceeding the ozone standard puts individuals’ health at risk and could result in regulatory changes that would affect residents and local businesses,” Gorman said. In Pima County during 2014, there were 42 days when ozone levels were in the ‘moderate’ range and one day when the pollutant’s levels were in the ‘unhealthy for sensitive groups’ range.

    The U.S. EPA has proposed changing the ozone standard to make it even more protective of public health. The deadline for the announcement of this EPA decision is October 2015. If the standard is made more protective by EPA, our ozone levels will likely violate that new standard.

    Children’s health is at risk when ozone levels are elevated because they breathe in more air per pound of body weight and they play outside more than adults.  Others who are negatively affected by ozone include senior citizens, people who work or exercise outdoors, people with lung disease and individuals who are unusually sensitive to ozone. Residents can view up-to-the-hour air quality information to avoid unnecessary exposure to elevated levels of air pollution.

    What actions can be taken to reduce the emissions that contribute to ground-level ozone?

    • Pick one day a week for a “No-Drive Day” and reduce pollution by 1,000 pounds a year
    • Drive less by carpooling, walking, biking or taking public transportation
    • Avoid engine idling
    • Combine errands into one trip
    • Keep your vehicle well-maintained, including proper tire pressure
    • Reduce electricity use
    • Avoid the use of charcoal lighter fluid when barbequing
    • Use manual gardening equipment instead of gas-powered
    • Fill your gas tank in the evening hours during the summer, so the gasoline fumes don’t have the strong solar radiation available to form ozone

    For more information on air pollution, visit the Pima County Department of Environmental Quality Clean Air Program or call (520) 724-7446.