PHOENIX — Regulators have issued an ozone high pollution advisory Tuesday and Wednesday for metro Phoenix.

The advisory was issued because the area’s ozone levels are expected to exceed the federal health standard for air quality.

Regulators say people with respiratory problems should limit their outdoor activities on Tuesday and Wednesday.

Other recommendations include driving as little as possible, using carpools or public transportation, avoiding drive-thru lines and making sure that containers with household cleaners and other chemicals are sealed to prevent vapors from evaporating into the air.

Ozone forms when vehicle exhaust and chemical solvents combine with heat and sunlight.