Senior Airman Alexis Lopez, dental assistant with the 319th Medical Group, demonstrates proper sanitary procedure by putting on a face mask at the medical treatment facility at Grand Forks Air Force Base, N.D., Sept. 7, 2017. Lopez said in addition to personal sanitation, there are also multiple steps taken to ensure treatment rooms are sanitary and prepared for patient use. (U.S. Air Force photo by Airman 1st Class Elora J. Martinez)