UVGI System Modeling

Abstract

The modeling of systems for air and surface disinfection can be used to assess the UV dose, which can then be used to determine disinfection rates for specific microbes. The modeling of UV irradiance fields can produce fairly accurate results for the purposes of system sizing. Several components in UV disinfection systems may require modeling – the lamp UV irradiance, the reflective enclosure, if any is used, and the total UV dose imparted by any UV system. The methods presented here can be adapted to evaluating any type of air and surface disinfection system, including cooling coil irradiation systems, Upper Room systems, packaging disinfection, air disinfection, and food disinfection. This chapter presents modeling methods and tools that are available and that have been well-corroborated by empirical data on UV lamps and microbial disinfection rates. These are computational methods and are best applied using software or spreadsheets. Models and methods have been presented in the literature other than those given here, and some of these are accurate while others are either less so or are theoretical models that have not yet been applied (Buttolph and Haynes 1950, Philips 1985, IESNA 2000, Gardner and Shama 1999, Krasnochub 2005). It is not the intent of this chapter to review or compare the various models, but to present the reader with a workable set of tools for designing UV systems for air and surface disinfection.