GENERAL CONFERENCE OF JAPAN ENVIRONMENTAL INFECTION –
STUDY THE EFFECTIVENESS OF THE SILENTAIR AIR PURIFIER

   
   
Test Performed By Dr. Kohno
Fukuoka University Hospital
February 1993
   
   
Purpose Infection by MRSA (Methicillin Resistance Staphylococcus Aureus) in hospitals has now become a great issue to be solved worldwide.

Ventilation is mandatory in order to protect patients from air infection in hospitals. However, ventilation is difficult in isolated patient rooms where opening of doors and windows is very limited. Under the circumstances, colony counts of falling MRSA and which were airborne in patient rooms were measured, and the effectiveness of SilentAir was studied on MRSA.
   
   
Study 1: Study of Falling MRSA in an Individual Patient Room
   
   
Patient A patient in a serious case (disease is not specified)
   
   
Places Measured Three places: in front of door, near patient's pillow and near air conditioner.
   
   
Period Studied Two 7-day periods before and after use of SilentAir.
   
   
Time Measured 1:00 a.m., 9:00 a.m., 5:00 p.m.
   
   
Results Significant decreases of MRSA colonies were observed. Counts of MRSA colonies in total, 9 plates were 91.3 before use of SilentAir and 54.8 after use.

It is presumed that the frequency of attendance by hospital staff to make drips and to replace bed sheets gave an observation of an insignificant decrease.
   
   
Study 2: Study of Airborne MRSA in an Individual Patient Room
   
   
Patient A serious case patient who vomited sputa in which MRSA was observed.
   
   
Period Studied Two 4-day periods before and after use of SilentAir.
   
   
Time Measured 1:00 a.m., 10:00 a.m., 5:00 p.m.
   
   
Analyzer Bio-Air Checker (50 liters/min.) Nikken Bio-Medical Laboratory.
   
   
Results Total counts of all kinds of airborne virus measured three times a day were significantly decreased from 32.8 before use of SilentAir to 15.5 after use. Similarly, counts of MRSA were decreased from 3.8 to 0.3.
   
   
Study 3: Comparison Study of Isolator and SilentAir Air Purifier in Falling Virus Counts
   
   
Patient Hemopathy patient
   
   
Places Measured Two places near patient's pillow in a vinyl tent and near boundary between bed and tent.
   
   
Period Studied Two 3-day periods before and after use of SilentAir.
   
   
Time Measured 1:00 a.m., 9:00 a.m., 5:00 p.m.
   
   
Results No significant difference was observed in total average counts: 8.3 when isolator was used and 9.3 when SilentAir was used.
   
   
Consideration Falling MRSA and airborne MRSA were significantly reduced when SilentAir was used in an individual patient's room.

It is estimated that SilentAir has an effectiveness equivalent to that of isolators, as no significant difference was observed in the comparison study on counts of falling virus in a tent.

Statements above show the SilentAir Air Purifier has an obvious effect on air cleaning in patients' rooms in hospitals. The SilentAir Air Purifier is recommendable for use in rooms with MRSA infected patients and for use to protect immunodeficient patients from air infections.

The difference between filtering air and purifying it.