The M.E.D.TM allows workers to enter and exit small man-size openings while maintaining continuous ventilation. Without such a device, duct fills the manhole opening, which prevents proper rapid entry and exit. Tightly integrated into the UB-Line of confined space ventilation equipment, the RAMFAN M.E.D.™️ system is quick to assemble, and the new swiveling elbow makes duct alignment easy.