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Ozone: Good up High, Bad Nearby

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Ozone: Good up High, Bad Nearby actions you can take High-Altitude “Good” Ozone Ground-Level “Bad” Ozone •Protect yourself against sunburn. When the UV Index is •Check the air quality forecast in your area. At times when the Air “high” or “very high”: Limit outdoor activities between 10 Quality Index (AQI) is forecast to be unhealthy, limit physical exertion am and 4 pm, when the sun is most intense. Twenty minutes outdoors. In many places, ozone peaks in mid-afternoon to early before going outside, liberally apply a broad-spectrum evening. Change the time of day of strenuous outdoor activity to avoid sunscreen with a Sun Protection Factor (SPF) of at least 15. these hours, or reduce the intensity of the activity. For AQI forecasts, Reapply every two hours or after swimming or sweating. For check your local media reports or visit: www.epa.gov/airnow UV Index forecasts, check local media reports or visit: www.epa.gov/sunwise/uvindex.html •Help your local electric utilities reduce ozone air pollution by conserving energy at home and the office. Consider setting your •Use approved refrigerants in air conditioning and thermostat a little higher in the summer. Participate in your local refrigeration equipment. Make sure technicians that work on utilities’ load-sharing and energy conservation programs. your car or home air conditioners or refrigerator are certified to recover the refrigerant. Repair leaky air conditioning units •Reduce air pollution from cars, trucks, gas-powered lawn and garden before refilling them. equipment, boats and other engines by keeping equipment properly tuned and maintained. During the summer, fill your gas tank during the cooler evening hours and be careful not to spill gasoline. Reduce driving, carpool, use public transportation, walk, or bicycle to reduce ozone pollution, especially on hot summer days. •Use household and garden chemicals wisely. Use low VOC paints and solvents. And be sure to read labels for proper use and disposal. Region 8 - (800) 227-8917 Region 2 www.epa.gov/region8/ - (212) 637-4249 For air program www.epa.gov/region2/ 10 1 information, 8 Region 5 - (312) 353-2211 contact www.epa.gov/region5/ 2 Region 10 - (206) 553-1505 www.epa.gov/region10/ Region 1 - (617) 918-1660 your Regional www.epa.gov/region1/ EPA Office: 5 EPA Headquarters 7 3 (202) 564-7400 9 http://www.ephttp://www.epa.gov/air ...or visit EPA’s website at Region 7 - (913) 551-7020 www.epa.gov/region7/ Region 3 - (215) 814-2100 http://www.epa.gov/air Region 9 - (415) 947-8715 www.epa.gov/region3/ www.epa.gov/region9/ 4 6 Region 4 - (404) 562-9077 www.epa.gov/region4/ Region 6 - (214) 665-7229 www.epa.gov/region6/ 2 about the cover... TOP: The “good” ozone layer in the stratosphere protects life on Earth from the Sun’s harmful ultraviolet (UV) rays. MIDDLE: Antarctic Ozone Thinning–shown in blue and purple, extended out over 16 million square miles or about the same size as North America (2001 NASA satellite image). BOTTOM: “Bad” ozone at ground-level is harmful to breathe and damages crops, trees, and other vegetation. United States Office of Air and Radiation EPA-451/K-03-001 Environmental MC6101A June 2003 Protection Agency 1200 Pennsylvania Avenue, NW Washington, DC 20460 PRINTED ON RECYCLED PAPER good up high bad nearby What is Ozone? What is Happening to the protective ozone layer. Research indicates What Causes “Bad” Ozone? breathe. Many urban and suburban emphysema, and asthma. “Bad” ozone also “Good” Ozone Layer? that depletion of the “good” ozone layer is areas throughout the United States have can reduce lung function and inflame the Ozone is a gas that occurs both in the being reduced worldwide. Thinning of the Ground-level or “bad” ozone is not high levels of “bad” ozone. But many linings of the lungs. Repeated exposure Earth’s upper atmosphere and at ground Ozone is produced naturally in the protective ozone layer can be observed emitted directly into the air, but is created rural areas of the country are also subject may permanently scar lung tissue. level. Ozone can be “good” or “bad” for stratosphere. But this “good” ozone is using satellite measurements, particularly by chemical reactions between oxides of to high ozone levels as winds carry Healthy people also experience difficulty your health and the environment, gradually being destroyed by man-made over the Polar Regions. nitrogen (NOx) and volatile organic emissions hundreds of miles away from depending on its location in the chemicals referred to as ozone-depleting compounds (VOC) in the presence of their original sources. breathing when exposed to ozone atmosphere. substances (ODS), including sunlight. Emissions from industrial pollution. Because ozone forms in hot weather, anyone who spends time outdoors chlorofluorocarbons (CFCs), How Does the Depletion of facilities and electric utilities, motor hydrochlorofluorocarbons (HCFCs), “Good” Ozone Affect Human vehicle exhaust, gasoline vapors, and How Does “Bad” Ozone Affect in the summer may be affected, How Can Ozone Be Both Good halons, methyl bromide, carbon chemical solvents are some of the major particularly children, outdoor workers and Health and the Environment? Human Health and the people exercising. Millions of Americans and Bad? tetrachloride, and methyl chloroform. sources of NOx and VOC. Environment? These substances were formerly used and Ozone depletion can cause increased live in areas where the national ozone Ozone occurs in two layers of the sometimes still are used in coolants, amounts of UV radiation to reach the Earth At ground level, ozone is a harmful health standards are exceeded. atmosphere. The layer closest to the Earth’s pollutant. Ozone pollution is a concern Breathing ozone can trigger a variety of foaming agents, fire extinguishers, which can lead to more cases of skin cancer, Ground-level or “bad” ozone also damages surface is the troposphere. Here, ground- during the summer months because strong health problems including chest pain, solvents, pesticides, and aerosol cataracts, and impaired immune systems. vegetation and ecosystems. It leads to level or “bad” ozone is an air pollutant that propellants. Once released into the air Overexposure to UV is believed to be sunlight and hot weather result in harmful coughing, throat irritation, and is harmful to breathe and it damages ozone concentrations in the air we congestion. It can worsen bronchitis, reduced agricultural crop and commercial these ozone-depleting substances degrade contributing to the increase in melanoma, forest yields, reduced growth and crops, trees and other vegetation. It is a very slowly. In fact, they can remain the most fatal of all skin cancers. Since survivability of tree seedlings, and main ingredient of urban smog. The intact for years as they move through the 1990, the risk of developing melanoma has troposphere generally extends to a level All other sources increased susceptibility to diseases, pests troposphere until they reach the more than doubled. and other stresses such as harsh weather. about 6 miles up, where it meets the stratosphere. There they are broken Industrial/ In the United States alone, ground-level second layer, the stratosphere. The down by the intensity of the sun’s UV UV can also damage sensitive crops, such stratosphere or “good” ozone layer extends as soybeans, and reduce crop yields. Some Commercial/ ozone is responsible for an estimated $500 rays and release chlorine and bromine Residential million in reduced crop production each upward from about 6 to 30 miles and scientists suggest that marine Motor molecules, which destroy the “good” Fuel Combustion protects life on Earth from the sun’s phytoplankton, which are the base of the Vehicles year. Ground-level ozone also damages the ozone. Scientists estimate that one foliage of trees and other plants, affecting harmful ultraviolet (UV) rays. chlorine atom can destroy 100,000 ocean food chain, are already under stress from UV radiation. This stress could have the landscape of cities, national parks and “good” ozone molecules. forests, and recreation areas. Too little there… Many popular consumer adverse consequences for human food products like air conditioners and Even though we have reduced or supplies from the oceans. refrigerators involve CFCs or halons eliminated the use of many ODSs, their What is Being Done About use in the past can still affect the during either manufacture or use. Over What is Being Done About the “Bad” Ozone? time, these chemicals damage the earth’s Utilities protective ozone layer. Depletion of “Good” Ozone? Under the Clean Air Act, EPA has set protective health-based standards for ozone The United States, along with over 180 other countries, recognized the threats in the air we breathe. EPA, states, and cities posed by ozone depletion and in 1987 have instituted a variety of multi-faceted Sources of NOx programs to meet these health-based adopted a treaty called the Montreal Protocol to phase out the production and standards. Throughout the country, use of ozone-depleting substances. additional programs are being put into place Consumer Solvents to cut NOx and VOC emissions from EPA has established regulations to phase vehicles, industrial facilities, and electric out ozone-depleting chemicals in the utilities. Programs are also aimed at reducing United States. Warning labels must be Motor pollution by reformulating fuels and placed on all products containing CFCs or Vehicles consumer/commercial products, such as similar substances and nonessential uses of paints and chemical solvents, that contain ozone-depleting products are prohibited. VOC. Voluntary programs also encourage Releases into the air of refrigerants used in communities to adopt practices, such as car and home air conditioning units and carpooling, to reduce harmful emissions. appliances are also prohibited. Some substitutes to ozone-depleting products Industrial/ have been produced and others are being Commercial We live with ozone every day.
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