“…Inactivation rate constants (k-values) are species-dependent and relate the susceptibility of a given microorganism population to UV radiation (Hollaender 1943;Jensen 1964;Sharp 1939Sharp , 1940. Measured k-values for many species of viruses, bacteria, and fungi have been published in the scientific literature and previously summarized (Brickner et al 2003;Kowalski 2009;Philips 2006). As shown in Figure 4, bacteria are generally more susceptible to UVC energy than fungi, but this is not always the case (see Chapter 17 of the 2016 ASHRAE Handbook-HVAC Systems and Equipment).…”