The inactivation and removal of airborne Bacillus atrophaeus endospores from air circulation systems using UVC and HEPA filters.
J Appl Microbiol
; 104(2): 489-98, 2008 Feb.
Article
in En
| MEDLINE
| ID: mdl-17927759
ABSTRACT
AIMS:
To (i) evaluate the UV radiation in the 'C' band/high efficient particulate air (UVC/HEPA) instrument's potential to inactivate spores of Bacillus atrophaeus and selected Bacillus species and (ii) test whether a titanium dioxide coating inside the cylindrical HEPA filter improves the system's efficacy. METHODS ANDRESULTS:
Known amounts of dried spore preparations of B. atrophaeus, Bacillus cereus, Bacillus megaterium, Bacillus stearothermophilus and Bacillus thuringiensis were exposed to the UVC lamp within a cylindrical HEPA filter for different time lengths (30 min to 48 h) and with different air flow speeds (0-235 l s(-1)). The log(10) reduction (range 5-16 logs) of colony forming units for spores exposed to the UVC compared with the unexposed spores was significant (P < 0.0001). The addition of a titanium dioxide (TiO(2)) veneer to the interior surface of the HEPA filter significantly increased the inactivation of spores (P < 0.0001).CONCLUSIONS:
The UVC/HEPA unit could inactivate spores of B. atrophaeus, B. cereus, B. megaterium, B. stearothermophilus and B. thuringiensis. SIGNIFICANCE AND IMPACT OF THE STUDY The UVC/HEPA unit represents an effective method of decontaminating circulating air within an air-duct system as found in a building.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Bacillus
/
Decontamination
/
Air Conditioning
/
Air Microbiology
Language:
En
Journal:
J Appl Microbiol
Journal subject:
MICROBIOLOGIA
Year:
2008
Document type:
Article
Affiliation country:
United States