Investigation of indoor environmental quality in urban dwellings with schoolchildren in Beijing, China

Abstract

This study attempts to collect more comprehensive data about the indoor environmental quality in urban dwellings with schoolchildren in Beijing, China. For this purpose, indoor air temperature, relative humidity and the levels of indoor chemical and biological pollutants in 14 households were measured in 2013. Results show that, in cold winter, indoor relative humidity was often lower than the comfort limit of 30%, while indoor CO 2 concentration was often higher than the acceptable level of 1000 ppm in poorly ventilated homes with high occupant load. Indoor PM 2.5 pollution was very severe with the highest level of 523 mg/m 3 in living room and 345 mg/m 3 in children's bedroom in winter. Compared with the recommended thresholds, the levels of indoor volatile organic compounds and carbonyl compounds in most homes were low. Cigarette smoke is an important indoor source of PM 2.5 , formaldehyde, acetaldehyde, acetone and benzene. Also, there are significant correlations between the concentration of total volatile organic compounds and other compounds (acetaldehyde, acetone, benzene and toluene). Furthermore, two phthalates: di (2-ethylhexyl) phthalate and din -butyl phthalate were frequently detected in house dust. Penicillium, Cladosporium, and Aspergillus were predominant fungi in indoor air. The fungal pollution levels in different seasons and rooms were also compared.

Indoor exposure levels of bacteria and fungi in residences, schools, and offices in China: A systematic review

“…68 Cladosporium may cause keratitis, skin lesions, sinusitis, onychomycosis, and pulmonary infections. 78 were found to be protective against asthma, and gram-negative rods in dust were found to be protective factors against atopy. 3 Studies also found that early exposure to pets reduced the risk of childhood asthma because of the rich environment microorganism.…”

Indoor environmental conditions in schoolchildren’s homes in central-south China

“…The winter indoor RH in Beijing was relatively low (<34%) due to central heating. 51 However, indoor RHs in some investigated homes from Shanghai and Changsha were greater than 70%, and the corresponding rates of RH !70% were 16.5% in Changsha and 60% in Shanghai, respectively. 2.…”

“…Indoor CO 2 level usually increases with an increase in occupant density. 51 In order to keep CO 2 concentration at an acceptable level, adequate natural ventilation should be maintained in homes with high density of occupants. concentration in all these homes exceeded the Chinese national standard GB 3095-2012 (75 lg/m 3 ).…”

Can plants be considered a building service?

“…Data post 2010 is taken from literature. 43,44,50,51,[56][57][58][59][60][61][62][63][64][65][66][67][68][69][70] significantly in the next 100 years. 30 Several health guidelines exist for maximum safe CO 2 concentrations, with the lowest 8 h guideline being recommended by ASHRAE at 1000 ppm.…”