What is Ozone Pollution?

Ozone pollution is a concern in the warmer months of April through September. Ground level ozone is formed by a chemical reaction that needs heat from sunlight, nitrogen oxides and volatile organic compounds (VOCs). Ozone Heath Watches are issued when the highest concentration of ozone pollution may approach the federal health standard.


Drive less. When possible, walk, ride a bike, carpool, van pool 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.

Re-fuel your vehicle after dark (or during cooler, evening hours).


During an Ozone High Pollution Advisory, leaf blowers & open burning/woodburning activity is restricted in Maricopa County. This includes individuals and businesses which have burn permits for open burning and woodburning fires at hotels and restaurants. are prohibited from being used in Maricopa County.