Effectiveness Study of Disinfection of Microbes by Innovation Robotic UVC Radiation: Response to COVID-19 Pandemic

Main Article Content

Pannika Vorapaluk


Background: During the COVID-19 pandemic, many
patients have been quarantined and hospitalized.
Healthcare providers thus have a high risk in contacting
the SARS-CoV-2. Measures for disinfection not involving
human works might decrease such risk and decrease
transmission rate inside the hospital.
Objectives: To study the effectiveness of innovative
robotic ultraviolet C (UVC) radiation in killing Pseudomonas
aeruginosa as a surrogate for SARS-CoV-2.
Materials and methods: The robotic UVC comprised of
12 UVC lamps (TUV 36W SLV) forming in cylinder shape
perpendicular to robotic 4 wheels base controlled direction
of movement by remote control. P. aeruginosa are
common etiology of hospital-acquired infection and

generally tolerate to UVC more than the coronaviruses.
We studied killing effect of innovative robotic UVC to these
bacteria on various surfaces including glass, plastic and
stainless-steel at 0.5-3 meters from the device.
Results: Under the same exposure time and UVC dose,
eradication of P. aeruginosa on the glass surface was the
hardest comparing to other surfaces. This robotic
innovation was effective in killing 99.9% of P. aeruginosa
on the plastic and the stainless-steel surfaces within 3
minutes at the distance of 3 meters from the device. When
the exposure time was increased to 10 minutes, 99.9% of
the microbes on all surfaces in this study were killed.
Conclusion: Robotic UVC radiation was effective in killing
P. aeruginosa, which is more tolerate to UVC than the
coronaviruses. Implementing UVC radiation might help
decrease risk of hospital transmission in operating theater,
intensive care unit or cohort ward.

Article Details

Original articles


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