A poor air quality warning is posted over a highway Wednesday, Jan. 23, 2013, in Salt Lake City. A group of doctors is declaring a health emergency over northern Utah's lingering pollu

 

              A poor air quality warning is posted over a highway Wednesday, Jan. 23, 2013, in Salt Lake City.  A group of doctors is declaring a health emergency over northern Utah
A poor air quality warning is posted over a highway Wednesday, Jan. 23, 2013, in Salt Lake City. A group of doctors is declaring a health emergency over northern Utah's lingering pollution problem. Utah Physicians for a Healthy Environment planned to deliver a petition Wednesday demanding immediate action by elected officials. (AP Photo/Rick Bowmer)