The Charlotte region is under a “Code Red” air quality alert Tuesday for the first time since late June 2012.
Code Red means the potential exists for unhealthy ozone levels. It means everyone should try to limit their time outdoors, not just children, older adults and people with respiratory conditions.
The N.C. Department of Environmental Quality in Raleigh issued the Code Red alert for Charlotte until 8 p.m. Tuesday.
Charlotte hasn’t seen a Code Red day in recent years largely because of wet summers, said Tom Mather, spokesman for the N.C. Division of Air Quality.
Hot, still air and lots of sunshine combine with auto and smokestack emissions to raise ozone levels.
Code Red days were declared every third day somewhere in the state in the late 1990s and early 2000s, but new regulations to cut smokestack and auto emissions helped to reduce ozone levels over the years, Mather said. Those efforts included the N.C. Clean Smokestacks Act approved by legislators in 2002.
The Charlotte area has experienced four “Code Orange” days this year, including Monday. That’s one level below Code Red and means air quality is potentially unhealthy for sensitive groups and people exercising or working outdoors for prolonged periods.
Code Orange is forecast Wednesday for the Charlotte area.
The Charlotte region had two Code Orange days in 2015 and none in 2014 and 2013.