Germicidal UV Sources and Systems†

Abstract

The COVID-19 pandemic has generated great interest in reviving an old intervention technology, particularly for air disinfection—ultraviolet germicidal irradiation (UVGI). Since UVGI was developed and refined more than 80–90 years ago, the ultraviolet source of choice has been almost exclusively the low-pressure mercury vapor discharge lamp. Today, with new lamp technologies, there has been significant interest in the application of ultraviolet light-emitting diodes and excimer lamps that emit in the UV-C (180–280 nm) spectral band. This paper reviews these competing technologies with the aim of giving a sound basis for decisions on how to choose and install UV systems for disinfection of air and surfaces given the COVID-19 pandemic.