Hospitals often use the Hospi-Guard air purifier in intensive areas where an extra measure of precautions and cleanliness is needed. Even though other measures have been introduced to scrub the office air, this unit is placed in our waiting area/front office where patients and other visitors/staff may tend to congregate. Basically this is a method of protection stacked upon other protection. These units provide HEPA and internal UV sanitation. See www.Envirco.com for more information.