Study On Indoor Air Quality At Rural Houses In Severe Cold Region

The heating period lasts6months in severe cold region. The peasants take strawand inferior coal as the primary fuels, which make indoor air polluted seriously. Theprimary fuels taken by the peasents are straw and inferior coal which may bring outpoor indoor air quality.To explore the indoor air pollution at rural houses in severe cold region, a fieldstudy was conducted from July,2012to May,2013. The pollutants including PM_2.5,PM₁₀, TVOC, CO₂, CO, SO₂, NO_Xand NH₃were monitored and the subjectivequestionnaires were administered simultaneously.2074data and129questionnaireswere collected.The results showed that93%,75%,23.3%,61.7%,99.2%and64.2%of thesamples for the PM_2.5, PM₁₀, CO, CO₂, SO₂and NO_x exceeded the limits required in thestandard. The mean concentrations of them were0.369mg/m³,0.414mg/m³,12.7ppm,1363ppm,0.42ppm and0.24ppm, which were3.9,1.8,0.6,0.4,2.6and0.6times higherthan the values specified in the standard, respectively. It is indicated that PM_2.5, PM₁₀,SO₂, NO_x, CO₂in most of the samples exceeded the normal levels seriously. Above all,PM_2.5, PM₁₀, CO, CO, SO₂and NO_x were the main pollutants that affect the indoor airquality at rural houses in Chinese severe cold area. The indoor air quality at rural houseswas quite poor.Most peasants were satisfied with the indoor air quality even with the strong sootodor and foul sense. However, it is found that there was a quite high prevalence ofrespiratory disease among the respondents. More attention should be paid to the indoorair quality at rural houses.The straw burning affected PM_2.5, CO and CO₂greatly. However, there was notsignificant influence on SO₂. It also showed higher concentrations of PM_2.5and CO inbedroom than kitchen. In addition, the concentrations of PM_2.5and CO in bedroom werehigher than those in kitchen.There were significant differences of the pollutants in different seasons. Badsealing of Chinese kang or firewall contributed most to the poorer indoor air quality atsome houses than others. It also showed that the concentrations of most indoorpollutants were higher than the equivalents outdoor in the later heating period.The multiple linear regression models for PM_2.5were proposed by themethod ofstepwise regression. There were good relations between PM₁₀and PM_2.5, CO and PM_2.5,PM₁₀and CO, respectively. In addition, linear correlations were also found between SO₂and CO₂, NO_Xand SO₂, respectively. Some measures were proposed to improve theindoor air quality at rural houses in severe cold region at last.