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  • Early return of ground-level ozone season possible

    Mar 27, 2018 | Read More News
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    Now that spring has officially sprung and the angle of the sun is becoming more direct above us, our region will see increased ground-level ozone in the air we breathe. In the layer far above the surface of the Earth, ozone helps protect our planet from solar radiation. However, when ozone forms at “nose-level” from various emissions reacting with intense sunlight, it is harmful to our health. In Pima County, the largest single source of the emissions that form ozone is motor vehicle use.air quality
    In the past, elevated ozone levels typically began in May, but last year Pima County Department of Environmental Quality (PDEQ) monitors detected elevated ozone levels in April. Depending on weather conditions and emissions in the air, we could see that trend continue this year. Driving and idling less will help reduce some of the emissions that combine to form ozone.
    In 2015, the U.S. Environmental Protection Agency (EPA) changed the National Ambient Air Quality Standard (NAAQS) for ozone to make it more protective of public health. Ozone levels in Pima County are now very close to violating the health standard.
    How Close Are We to the EPA Ozone Standard? Ozone levels are just under the EPA health standard. The EPA NAAQS for ozone is 0.070 parts per million (8-hour average) and the 3-year average levels in Pima County are at 0.069 ppm.

    What Does Ozone Do To Our Health?
    • According to EPA, ozone can have the follow health effects:
    • Make it more difficult to breathe deeply and vigorously.
    • Cause shortness of breath and pain when taking a deep breath.
    • Cause coughing and sore or scratchy throat.
    • Inflame and damage the airways.
    • Aggravate lung diseases such as asthma, emphysema, and chronic bronchitis.
    • Increase the frequency of asthma attacks.
    • Reduce lung function and harm lung tissue.
    • Make the lungs more susceptible to infection.
    • Continue to damage the lungs even when the symptoms have disappeared. Cause chronic obstructive pulmonary disease.
    The health effects from unhealthy levels of ozone can lead to increased school and work absences, medication use, visits to doctors and emergency rooms, and hospital admissions.
    Who Is At Risk? People most at risk from breathing air containing unhealthy levels of ozone include people with asthma and other respiratory illnesses, children, older adults, and people who are active outdoors, especially outdoor workers.  If you are sensitive to ozone, you can let your health care provider know that EPA has developed a course for medical providers to teach them more about ground-level ozone.
    Who Determines if We Violate the Standard?  EPA decides if our region meets the new health standard by using an average of the most recent three years of ozone data from PDEQ monitors. Reducing ozone levels will be key in keeping Pima County in attainment of the new EPA standard.
    What Can We Do To Keep Ozone Levels Healthy? As previously mentioned, one of the largest single sources of the ingredients that form ozone are vehicle emissions. The good news is we can take individual actions on a daily basis to keep the air healthy to breathe. There are multiple ways to reduce ozone including: driving less and sharing rides, taking transit, biking, and walking when possible; limiting engine idling; combining errands into one trip; keeping tires properly inflated, stopping at the click when refueling to avoid spills; refueling after 6 p.m. during the summer; and conserving electricity.
    How Can We Protect Ourselves If We Are Sensitive to Ozone? Know what air pollution levels are before going out and, if levels are high, spend less time outdoors and reduce your level of excursion if outside. The Pima County Department of Environmental Quality (PDEQ) monitors for ozone at eight different monitoring sites throughout eastern Pima County. Five-day Air Quality Forecasts are now available through Arizona Department of Environmental Quality. Real-time air quality data is provided on the PDEQ website and the public can sign up with PDEQ to receive air quality advisories when high pollution levels are imminent via email or through Twitter @PimaDEQ.