Ultraviolet germicidal irradiation (UVGI) is an important technology used to improve indoor air quality in a wide variety of applications, from residences and schools to highly sensitive healthcare facilities. There is a false perception that HEPA air filters sufficiently sterilize air, but studies demonstrate that while filters are necessary, they are not sufficient to neutralize the smallest particulates — UVGI can be a key partner in this battle. This course will review the importance of optimizing indoor air quality for building occupants and how ultraviolet air purification can be used to sanitize surfaces and air, remove odors, and reduce allergens. The course will also examine how to properly engineer an ultraviolet germicidal irradiation system to ensure it operates optimally when used in conjunction with ventilation and filtration systems.