Model Evaluation of Secondary Chemistry due to Disinfection of Indoor Air with Germicidal Ultraviolet Lamps

• DOI: 10.1021/acs.estlett.2c00599
• Publication Date: 2022-12-02T16:01:41Z
• Authors: Zhe Peng; Shelly L. Miller; Jose L. Jimenez
• Keywords: Ultraviolet

Air disinfection using germicidal ultraviolet light (GUV) has received increasing attention during the COVID-19 pandemic. GUV uses UVC lamps to inactivate microorganisms, but it also initiates photochemistry in air. However, GUV's indoor-air-quality impact not been investigated detail. Here, we model chemistry initiated by at 254 ("GUV254") or 222 nm ("GUV222") a typical indoor setting for different ventilation levels. Our analysis shows that GUV254, usually installed upper room, can significantly photolyze O3, generating OH radicals oxidize volatile organic compounds (VOCs) into more oxidized VOCs. Secondary aerosol (SOA) is formed as VOC-oxidation product. GUV254-induced SOA formation of order 0.1–1 μg/m3 cases studied here. GUV222 (described some harmless humans and thus applicable whole room) with same effective virus-removal rate makes smaller mid-to-high rates. This mainly because lower UV irradiance needed less efficient OH-generating O3 photolysis than GUV254. higher GUV254 under poor due small significant photochemical production nm, which does occur