Indoor microbial contaminants may induce the eye stimulation, asthma, allergic dermatitis and pneumonia and infectious diseases as well, even to die due to the serious infection. The main contamination source is constructional materials (especially the decorative materials) of the inner space of the building as well as the electric appliance (especially the center air conditioner system). Not only the direct stimulation from the chemicals released, but also all of them provide a suitable environment for some pathogenic microorganisms in the inner space of room. Using the anti-microorganism decorative materials to inhabit/decrease the microorganisms may improve the indoor air quality.

Objective To evaluate the removal effectiveness of air pollutants by photocatalytic nanocomposite coating. Methods TiO2-coated glass board was exposed to UV light of 365 nm in chamber with volume of 4 m3. The purification efficiencies of TiO2 nanocomposite coating for SO2?NO2 and formaldehyde were determined at light intensity of 107-271 ?W/cm2 and wind velocity of 0.3-1.5 m/s. Results The purification efficiencies of TiO2-coated glass board treated under this experimental condition for 30 min were 97%?90%, 69% for SO2?NO2 and formaldehyde in indoor air respectively, and only 48% for SO2 without exposure to UV light. Conclusion This method provided basic data for establishing an evaluation method for purification effectiveness of photocatalytic nanocomposite coating for indoor air pollutants. Further approach was needed for exploring the effects of various environmental influential factors on the purification effectiveness of TiO2 nanocomposite coating.