Thousands of residents in communities across parts of Alaska, Pennsylvania, and Alabama have been advised to stay indoors on Tuesday, February 10, as pockets of fine particle pollution (PM2.5) have reached "unhealthy" and "unhealthy for sensitive groups" levels, according to the Environmental Protection Agency ( EPA ) and National Weather Service (NWS) alerts. According to the NWS alerts , Fairbanks city in Alaska, the Liberty/Clairton area—including Clairton, Glassport, Lincoln, Liberty, and