Evaluating the efficacy of a rotating upper-room UVC-LED irradiation device in inactivating aerosolized Escherichia coli under different disinfection ranges, air mixing, and irradiation conditions

Nunayon, Sunday S.; Wang, Minghao; Zhang, Hui H.; Lai, Alvin C.K.

doi:10.1016/j.jhazmat.2022.129791

Cited by 18 publications

(13 citation statements)

References 34 publications

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“…The dose–response relationship exhibited a first-order decay without any observable shoulder or tail, indicating that a single-stage dose response was observed. This first-order kinetic decay has also been widely observed in other air disinfection studies including a scaled chamber, full-scale room, and small cylindrical UV unit . The order of bacterial inactivation efficacy of different UV wavelengths was 268 nm > 254 nm > 222 nm > 298 nm > 311 nm > 365 nm.…”

Section: Resultssupporting

confidence: 69%

Evaluating the Performance of UV Disinfection across the 222–365 nm Spectrum against Aerosolized Bacteria and Viruses

Lu,

Wang,

Liu

et al. 2024

Environ. Sci. Technol.

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Bioaerosols play a significant role in the transmission of many infectious diseases, especially in enclosed indoor environments. Ultraviolet (UV) disinfection has demonstrated a high efficacy in inactivating microorganisms suspended in the air. To develop more effective and efficient UV disinfection protocols, it is necessary to evaluate and optimize the effectiveness of UV disinfection against aerosolized bacteria and viruses across the entire UV spectrum. In this study, we evaluated the performance of UV disinfection across the UV spectrum, ranging from 222 to 365 nm, against aerosolized bacteria and viruses, including Escherichia coli, Staphylococcus epidermidis, Salmonella enterica, MS2, P22, and Phi6. Six commonly available UV sources, including gas discharge tubes and light-emitting diodes with different emission spectra, were utilized, and their performance in terms of inactivation efficacy, action spectrum, and energy efficiency was determined. Among these UV sources, the krypton chloride excilamp emitting at a peak wavelength of 222 nm was the most efficient in inactivating viral bioaerosols. A low-pressure mercury lamp emitting at 254 nm performed well on both inactivation efficacy and energy efficiency. A UV light-emitting diode emitting at 268 nm demonstrated the highest bacterial inactivation efficacy, but required approximately 10 times more energy to achieve an equivalent inactivation level compared with that of the krypton chloride excilamp and low-pressure mercury lamp. This study provides insights into UV inactivation on bioaerosols, which can guide the development of effective wavelength-targeted UV air disinfection technologies and may significantly help reduce bioaerosol transmission in public areas.

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Section: Resultssupporting

confidence: 69%

Evaluating the Performance of UV Disinfection across the 222–365 nm Spectrum against Aerosolized Bacteria and Viruses

Lu,

Wang,

Liu

et al. 2024

Environ. Sci. Technol.

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“…However, it is hazardous to human health, being both carcinogenic and damaging to eye tissues, and can hardly be applied to living beings. Therefore, it is mainly used for environmental disinfection in clinical and daily life ( 27 ). The wavelength at 260 to 265 nm is considered to inactivate microbes mainly by nucleic acid damage and CPD damage ( 41 ).…”

Section: Discussionmentioning

confidence: 99%

“…UV C (UVC) light within the range of 200 to 280 nm is in widespread use for disinfection of water ( 23 – 25 ), food processing ( 26 ), and air disinfection of hospitals, laboratories, and daily life ( 27 ). It is one of the most common techniques for inactivating pathogenic microorganisms ( 28 ).…”

Section: Introductionmentioning

confidence: 99%

UV C Light from a Light-Emitting Diode at 275 Nanometers Shortens Wound Healing Time in Bacterium- and Fungus-Infected Skin in Mice

et al. 2022

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“…O uso da luz UV-C é eficiente na eliminação de microrganismos na superfície dos materiais, juntamente com bioaerossóis 16 , entretanto, a eficácia da luz pode apresentar alguns obstáculos como: o posicionamento da luz frente a superfície a ser descontaminada, o tempo de exposição à luz e a presença de impurezas que possam bloquear o contato da luz a superfície 11,17,18 . Esses interferentes influenciam diretamente nos danos causados no DNA dos vírus ou bactéria, podendo ter o efeito descontaminante reduzido se a luz for mal inspecionada e utilizada 11 .…”

Section: Introductionunclassified

Avaliação Da Eficácia Da Luz Ultravioleta Contínua Na Descontaminação De Cédulas Do Real

Brito,

Camargo,

Cardoso

2024

EVS

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As mãos são vias de transmissão de microrganismos pois entram em contato com diferentes objetos no dia a dia, incluindo o dinheiro. Com o desgaste das cédulas, ocorre acúmulo de umidade, impurezas e bactérias, que são favorecidas pelo óleo produzido na polpa dos dedos e depositados em meio às rachaduras no papel-moeda. Embora a luz ultravioleta contínua (UV-C) possa ser empregada na descontaminação de objetos e superfícies, é necessário conhecer o tempo de exposição ideal, para assim, utilizá-la de forma eficiente. Esse estudo objetivou avaliar a eficácia da exposição à UV-C na descontaminação de cédulas do real. Foram analisadas quatro cédulas sendo três de R$2,00 e uma de R$5,00, selecionadas aleatoriamente. Os experimentos foram realizados em duplicata no Laboratório Clínico da PUC Goiás, empregando-se os meios de cultura TSB e PCA. As amostras foram coletadas com swabs umedecidos em caldo TSB estéril, antes e após a exposição das cédulas à luz UV-C durante 5, 10 e 20 minutos. Após a coleta, as amostras foram semeadas em caldo TSB e incubadas à 36ºC. Após 24h, 100μl do caldo TSB foram semeados na superfície do ágar PCA, o qual foi incubado à 36ºC por 24h. Na sequência realizou-se a leitura dos experimentos. Os resultados evidenciaram a presença de de microrganismos mesófilos aeróbios totais (MMAT) em todas as cédulas avaliadas antes e após exposição durante 5 e 10 minutos à luz UV-C. Por outro lado constatou-se que após 20 minutos de exposição à luz UV-C, houve 100% de descontaminação das cédulas do real.

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Evaluating the efficacy of a rotating upper-room UVC-LED irradiation device in inactivating aerosolized Escherichia coli under different disinfection ranges, air mixing, and irradiation conditions

Cited by 18 publications

References 34 publications

Evaluating the Performance of UV Disinfection across the 222–365 nm Spectrum against Aerosolized Bacteria and Viruses

Evaluating the Performance of UV Disinfection across the 222–365 nm Spectrum against Aerosolized Bacteria and Viruses

UV C Light from a Light-Emitting Diode at 275 Nanometers Shortens Wound Healing Time in Bacterium- and Fungus-Infected Skin in Mice

Avaliação Da Eficácia Da Luz Ultravioleta Contínua Na Descontaminação De Cédulas Do Real

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