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Surface disinfection by exposure to germicidal UV light
G Katara1, N Hemvani, S Chitnis
1Department of Microbiology and Immunology, Choithram Hospital and Research Centre, Manik Bagh Road, Indore - 452 014, MP, India.
Indian Journal of Medical Microbiology
|August 13, 2008
Summary
Germicidal ultraviolet (UV) light effectively inactivates medically important bacteria, bacterial spores, and fungi. A 30-minute exposure at up to eight feet demonstrates significant microbial reduction.
Area of Science:
- Microbiology
- Environmental Science
- Public Health
Background:
- Germicidal ultraviolet (UV) light is a recognized method for microbial disinfection.
- Standardization of UV-C irradiation parameters is crucial for effective microbial control.
Purpose of the Study:
- To design a model for assessing germicidal UV tube efficacy.
- To standardize UV light parameters (position, distance, time).
- To evaluate UV efficacy against medically important bacteria, spores, and fungi.
Main Methods:
- Microbial cultures including gram-positive and gram-negative bacteria, bacterial spores, and fungal spores were used.
- Microbes streaked on solid media were exposed to germicidal UV light.
- Inactivation was quantified through microbial counts post-exposure.
Main Results:
- UV light achieved a four-log reduction in bacterial populations.
- Effective bacterial inactivation was observed up to a distance of eight feet.
- An exposure time of 30 minutes was found to be adequate for significant microbial inactivation.
Conclusions:
- A simple model can effectively assess germicidal UV tube efficacy.
- Standardized UV irradiation parameters ensure consistent disinfection.
- Germicidal UV light is a potent tool for controlling medically relevant microorganisms.
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