The public ‐health significance of far‐UVC‐induced indoor ozone and its associated secondary chemistry

Far-UVC (around 220  nm) produces very low levels of ozone—in real-world indoor rooms compliant with far-UVC dose limits, far-UVC-induced ozone levels are<<10  ppb. At these very low ozone levels, there is no epidemiological evidence of increased health risks from any of the very large outdoor ozone studies Indoors, at the low ozone concentrations of relevance here, ozone does not react rapidly enough with preexisting airborne volatile organic compounds to compete with even extremely low levels of room ventilation, so significant ozone-induced ultrafine particle production is very unlikely. Direct measurements in real-life room scenarios are consistent with these conclusions. AbstractThere has been much recent interest in whole-room far-UVC (wavelength around 222  nm) to markedly and safely reduce overall levels of airborne pathogens in occupied indoor locations. Far-UVC light produces very low levels of ozone—in real-world scenarios induced ozone levels of less than 10 ppb, and much less in moderately or well-ventilated rooms compliant with US far-UVC dose recommendations, and very much less in rooms compliant with international far-UVC dose standards. At these very low ozone levels, there is no epidemiological evidence of increased health risks from any of the very large outdoor ozone studies, whether from ozone alone or from ozone plus associa ted pollutants. Indoors, at the low ozone concentrations of relevance here, ozone does not react rapidly enough w...
Source: Photochemistry and Photobiology - Category: Science Authors: Tags: INVITED REVIEW Source Type: research