Study on Indoor Air Quality Characteristics and Air Contaminants Control Strategies in Urban Residential Environment in Xi´an

Investigates the space-time distribution of indoor air pollution from five newly decorated residences in Xi´an and proposes its control methods. From Oct. 2007 to Nov. 2008, according to the GB/T18883-2002 Indoor Air Quality Standard, the airborne total volatile organic compounds (TVOC), benzene, formaldehyde, radon and dust PM₁₀ concentration were tracking test in difference spatial distribution in these residences 1,6 and 12 months after decorating. Through model experiment, TVOC divergence 1 month after decorating can be forecasted. After decorated 6 months, except for the individual measuring point (eg. stock room), the TVOC concentrations of other positions are below its standard value; However, after decorated 12 months, the exceeing standard rate of benzene concentration remains up to 62%; The concentration of formaldehyde and radon does not exceed its standard value during 12 months after decorating; the variation of PM₁₀ with time is not obvious. Indoor various spatial positons, the most seriously polluted rooms of TVOC and benzene are study and stock room. The inhomogeneity of spatial distribution changed with time is not obvious; But the dimensionless concentration of TVOC and benzene changed with time are followed the logarithmic function attenuation. Indoor air changes of ventilation is suggested not to be lower than 5.5 times /h^-1 for TVOC concentration reaching its standard requirement when inhabitants moved in 1 month after decorating.