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Fri, Apr 1, 2011

Ozone Season Begins April 1

PHOENIX (April 1, 2011) - The Valley enters its official ozone season today and does not conclude its watch for the ground level pollutant until the end of September.
Ozone pollution is granted a summertime status due to its need for interaction with heat and sunlight. Ground level ozone forms when emissions from fossil-fuel fired equipment, industrial and chemical processes, and even household activities react in the sun.

This summer, the U.S. Environmental Protection Agency is expected to announce a new, lower health standard for the pollutant. The agency states it is proposing to set the “primary” standard, which protects public health, at a level between 0.060 and 0.070 parts per million measured over eight hours. The current health standard is 0.075 ppm.

Last year was a busy one for air-quality forecasters. Ten days had exceedances of the federal ozone health standard. ADEQ issued five high-pollution advisories and 33 health watches for ozone during 2010.

“The health threat from ozone should motivate each of us to take action,” explains Maricopa County Air Quality Department Director Bill Wiley. “By making simple changes to our daily activities such as reducing our driving, refueling after dark or turning off lights, we can have a great impact on ozone concentrations.”

Ground level ozone pollution is a direct threat to your lungs and can trigger asthma. Children are at the greatest risk from ozone because their lungs are still developing, they are most likely to be active outdoors, and they are more likely than adults to have asthma. Adults with asthma or other lung diseases, and older adults are also sensitive to ozone.

“The condition of the Valley’s air quality is relative to the action we take to improve it,” said David A. Boggs, Valley Metro RPTA executive director. “As a commuter, take steps to reduce your travel one day a week by joining a carpool, riding transit or telecommuting.”

Ozone pollution prevention tips:

• Drive less. When possible carpool, vanpool, telecommute or use public transportation
• Avoid waiting in long drive-thru lines, for example, at coffee shops, fast-food restaurants or banks. Park your car and go inside
• Refuel your vehicle after dark or during cooler evening hours
• Use low-VOC (Volatile Organic Compounds) or water-based paints, stains, finishes and paint strippers
• Delay big painting projects until high-pollution advisories or health watches have passed
• Make sure containers of household cleaners, garage and yard chemicals and other solvents are sealed properly to prevent vapors from evaporating into the air
• Conserve electricity

To track how much pollution your commute generates, visit and select ShareTheRide. Sign up to receive air quality updates by email or text message at
OZONE BACKGROUND: Ground level ozone is formed by a chemical reaction that needs heat from sunlight, nitrogen oxides and volatile organic compounds [VOCs] to form. The months of April through September make up our Valley’s longer-than-normal “ozone season.”


The Arizona Department of Environmental Quality [ADEQ] provides a daily forecast for air quality. When conditions exist, ADEQ will issue high pollution advisories or health watches. Please visit or call (602) 771-2367. To receive the air quality forecast via email and/or text message please visit Mark Shaffer – (602) 771-2215 desk / (480) 433-9551 cell

The Maricopa County Air Quality Department is a regulatory agency whose goal is to ensure federal clean air standards are achieved and maintained for the residents and visitors of Maricopa County. The department is governed by the Maricopa County Board of Supervisors and follows air quality standards set forth by the federal Clean Air Act. The department offers air quality information and resources on its Clean Air Make More website. Please visit to learn more.
CONTACT: Holly Ward – (602) 506-6713 desk / (602) 526-7307 cell

Valley Metro/RPTA provides eco-friendly public transit options to residents of greater Phoenix and Maricopa County, including a clean-fuel bus fleet, low-emissions light rail, online carpool matching and bus trip mapping, and bicycle and telework assistance. Funding is provided by local, state and federal revenues; and administered by a board of 16 governments working to improve and regionalize the public transit system. Please visit to learn more.
CONTACT: Susan Tierney – (602) 523-6004 desk / (602) 292-4093 cell


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