On the qualities of the air as affected by radiant energies (photocatalytic ionization processes for remediation of indoor environments)

Airborne contaminants in indoor environments can affect the health of building occupants. Increased costs have prompted energy conservation and more stringent operational standards for buildings. Tight building envelopes reduce energy losses, but force reassessment of building designs and retrofits. The paradigm has shifted from "ventilation" to "comfort" to "indoor environmental quality" (IEQ). Various air treatment technologies can be used for control of trace contaminants. Conventional processes, such as sorption, filtration, and disinfection, are combined with advanced treatment processes (ATP), such as photocatalytic oxidation to oxidize volatile organic compounds (VOCs), bipolar air ionization to agglomerate particulate matter (PM_x), and ultraviolet disinfection to inactivate bioaerosols. Modular hybrid devices are integrated into engineered systems to control low levels of these contaminants. The extensive early development of these technologies is supplemented with improved diagnostic techniques applied to domestic, institutional, and commercial installations. Key words: indoor environmental quality, IEQ, advanced treatment, ultraviolet, UV, titanium dioxide, TiO₂, photocatalytic oxidation, PCO, volatile organic compounds, particulate matter, bioaerosols.