PHOENIX (AP) - Environmental regulators have issued another ozone pollution advisory for metro Phoenix.
The latest advisory was issued because the Phoenix area is expected to exceed the federal health standard for air quality on Tuesday.
Arizona Department of Environmental Quality officials recommend people with respiratory problems limit their outdoor activities on days of elevated ozone levels.
People are encouraged to drive only when necessary, use carpools or public transportation and avoid using gas-powered lawn equipment and drive-thru lines.
Ozone forms when vehicle exhaust and chemical solvents combine with heat and sunlight.