The influence of outdoor exposure concentrations on indoor air quality in rudimentary designed household structures: Mpumalanga Province, South Africa

Abstract

There is a belief that ambient air pollution is accountable for degrading the air quality indoors. Although in principle the indoor air quality should be better than that of outdoor air quality given the shielding effect of a house structure. However, ambient air quality can infiltrate and influence indoor air pollution concentrations in low-income urban informal settlements due to rudimentary designed household structures. Given this phenomenon, the current study endeavoured to explore the influence of outdoor exposure concentration on indoor air quality within the informal settlements of urban neighbourhoods. The exposure concentrations of indoor and outdoor particulate matter and nitrogen dioxide pollutants were simultaneously measured during summer and winter seasons. The GilAir Plus air sample pump was used to acquire measurements of particulate matter collected over 48 hours. While nitrogen dioxide gases were measured using passive diffusive samplers. All statistical analyses were performed using Python (version 3.8) Spyder. The current study has discovered that in many instances the results were comparable indoors and outdoors. For instance, this has been corroborated by the nitrogen dioxide discoveries where the current results were slightly comparable as indoor exposure concentrations values were recorded to be between (4 µg/m3 and 13 µg/m3), whilst the outdoor concentration ranged between (6 µg/m3 and 11 µg/m3). Likewise, a similar trend was observed for particulate matter exposure concentrations indoors (14 µg/m3 ) and (12 µg/m3) outdoors. The statistical inferences futher confirmed that the exposure values of indoor and outdoor were not significant (p>0.05) within the study areas of concern.