The hospital HVAC unit is a reservoir, amplifier and disseminator of microorganisms commonly attributed to HAIs. These microorganisms contribute to the growth of a complex microbiological material called “biofilm” (above) that adheres to HVAC coils and drain pans. Air quality studies show that these problematic microorganisms are circulated and are present in the air for inhalation by patients, increasing HAI risk. Air filtration and regular cleaning alone are insufficient. The solution is to address the underlying cause of contamination at the source.