Method for Evaluating Germicidal Ultraviolet Inactivation of Biocontaminated Surfaces

• Autorzy: Gorsuch E. L. , Grinshpun S. A. , Willeke K. , Reponen T. , Moss C. E. , Jensen P. A.
• Języki publikacji: EN

Abstrakty

EN

Safety issues related to work-site conditions often deal with potential worker exposure to infectious airborne microorganisms due to their dissemination in indoor air and contamination of surfaces. Germicidal ultraviolet (GUV) radiation is used in health-care settings and other occupational environments for microbial inactivation. In this study, a new methodology for determining the efficiency of GUV microbial inactivation of surfaces was developed and evaluated. The method utilizes identical chambers in which test microorganisms are irradiated on agar surfaces at different humidity and irradiation intensity levels. The effects of GUV intensity and exposure time on microbial inactivation were examined for Micrococcus luteus and Serratia marcescens. It was found that at low humidity levels (20-25%) both organisms can be inactivated with at least 95% efficiency if the GUV intensity exceeds 50 /zW/cm2 for at least 3-5 min (corresponding to a dose of ~ 1 0 mJ/cm2). The radiation dose needed for effective inactivation of S. marcescens, as measured by a UV meter near the microbial sample, was found not to be affected by the humidity level, whereas that of M. luteus increased at higher humidities. The findings of this study can be used to determine sufficient GUV inactivation doses for occupational environments with various microbial contaminations.

Słowa kluczowe

EN

UV inactivation; microorganisms; agar; colony; chamber

PL

mikroorganizmy; zanieczyszczenia mikrobiologiczne; powietrze; warunki pracy

• Wydawca: Taylor & Francis
• Czasopismo: International Journal of Occupational Safety and Ergonomics
• Rocznik: 1998
• Tom: Vol. 4, No. 3
• Strony: 287--297
• Opis fizyczny: Bibliogr. 15 poz., rys., tab., wykr.

Twórcy

autor

Gorsuch E. L.

• University of Cincinnati, USA

autor

Grinshpun S. A.

• University of Cincinnati, USA

autor

Willeke K.

• University of Cincinnati, USA

autor

Reponen T.

• University of Cincinnati, USA

autor

Moss C. E.

• National Institute for Occupational Safety and Health, USA

autor

Jensen P. A.

• National Institute for Occupational Safety and Health, USA

Bibliografia

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