April 8, 2021 341st OMRS, 819th RED HORSE conduct final swipe on density gauges Airman 1st Class Raul Rodriguez, 341st Operational Medical Readiness Squadron bioenvironmental engineer apprentice, conducts a radiation swipe test on a density gauge April 6, 2021, at Malmstrom Air Force Base, Mont. The density gauges use radiation to measure which areas need foundation during