The Utah Division of Air Quality’s summer season ozone no-drive "Choose-Clean-Air" program begins on May 1 each year and ends on September 30. During the summer ozone season, the Division’s Air Monitoring Center calls a "Choose Clean Air" alert when ozone pollution levels are expected to increase to unhealthy levels.
The voluntary summer season "ozone no-drive" or "Choose-Clean-Air" alert program primarily affects residents in Salt Lake, Davis, Utah and Weber counties. During an ozone no-drive "Choose-Clean-Air" alert day, people are asked to voluntarily reduce driving and avoid outdoor activities.
Ozone is an invisible gas caused by vehicle emissions in the presence of sunlight. It is a major health and environmental concern in Utah’s urban counties during the summer. Continued exposure to ozone can cause breathing problems, reduce lung function, irritate eyes and nasal passages and reduce resistance to colds and other infections.