  The physical basis and algorithm of the ultraviolet germicidal irradiation
(UVGI) scientific calculator are presented herein. The algorithm was
implemented in the web application UVGI Scientific Calculator (found at
https://covid-19-clean.org/calculator-journal-report/) that has been used to
facilitate the engineering and design of air-purifying equipment being
developed for use in hospitals, commercial and residential applications.
Presented examples of the calculations illustrate how different factors of the
construction of a UVGI air-purifier may influence the degree of virus
inactivation.
