Medical Air Solutions, Inc.

Entire Hospital Wing or Floor as a Negative Pressure Environment

             This question has arisen more than occasionally recently, “can you make an entire floor of  our hospital into a negative pressure ward?”.  The genesis of this concept was a public address by the Director of the CDC in January, 2003.  Dr. Julie Gerberding suggested the ideal method of containing a large number of people either infected with a common contagious disease or in the case of a biochemical attack would be to place them in a common, ward-like, enclosure.  Hospitals today are not built as they were in the early to mid-1900’s with wards to accommodate tubercular patients.  Today there are very few, if any, recently built hospitals with inclusion of a  ward concept of 10 to 50 beds or more. 

            It is possible to create negative pressure wings or an entire floor (or floors) of a hospital into a negative pressure environment in relation to the area immediately outside the isolated section.  The hallways would be negative in relation to the section outside the environment (with multiple 24/7 monitoring devices), but the rooms in the isolation area would have to be MORE negative than the hallways and other public parts of the isolated wing/floor. 

            The general areas could have negative pressure created by a BAS (building automation system, i.e., Johnson Controls, Siemens, etc.) controlling supply and returned air or by balancing dampers to create an offset of return air to supplied air.  The room, which must have a more negative environment than the hallways (and other public areas), would need to be brought up to the new JCAHO/AIA standards dated 1/1/03 of 12 ACH (air changes per hour)  and  a  negative 0.005” W.C. pressure.  These individual rooms would also have to be monitored 24/7 as per JCAHO’S  E.C. standard dated 10/1/03. 

            Most existing hospital AHU’s (air handling units) can be set to give the negative pressure in the general areas of the wing/floor with few problems, but most cannot deliver the 12 ACH and/or adequate negative pressure for the individual rooms.  If the hospital was constructed in the last few years, or so, they may have the capacity to do so, but this is not normally the case for older facilities.

Modular APS (air purification systems) would generally be the least costly and most efficient way to handle the individual room ACH and negative pressure requirements for the rooms involved. 

            The other challenge would be to totally seal the wing/floor from the area outside the isolated environment.   This takes time and a lot of patience, but it can be accomplished.               

            The alternative to isolating a wing or floor of the hospital is to erect a building outside the facility to house a specific number of patients.  This building would be, in HVAC terms, totally independent of the main air handling system of the hospital.  When not being used for emergency purposes, this area could be used as an “urgent care center” for non-critical emergency patients or as an outpatient clinic. 

  © 1999-2012 Medical Air Solutions, Inc. All rights reserved.