Airman 1st Class Joel Rogel, left, and William Raetz, 341st Medical Operations Squadron bioenvironmental engineering technicians, perform a ventilation survey inside a paint booth at the Auto Hobby shop April 8, 2015, Malmstrom Air Force Base, Mont. Bioenvironmental routinely monitor 66 ventilation systems across the base to ensure safe working conditions. (U.S. Air Force photo/Chris Willis)