Evaluation of Household Air Pollution of Carbon Monoxide and Nitrogen Dioxide Concentrations during Dry and Wet Seasons in a Mud Building that Uses Biomass Solid Fuel for Cooking in the Rural Area of Ifewara, Osun State, Nigeria

The use of biomass solid fuel (BSF) for cooking has an adverse effect on indoor air quality in homes. Consequently, the objective of this paper was to evaluate household air pollution (HAP) of carbon monoxide (CO) and nitrogen dioxide (NO2) concentrations during dry and wet seasons in a mud building that uses biomass solid fuel (BSF) for cooking in a rural area of Ifewara, Osun State, Nigeria, using appropriate standard procedures. Data obtained shows that the mean of CO and NO2 in the indoor spaces are 47.13 ppm and 1.94 ppm, respectively, with standard deviation (SD) of 28.77 ppm and 0.19 ppm, respectively. The results revealed significant differences in pollutant concentration levels between the two seasons. Indoor CO levels showed higher concentrations during dispersal from the kitchen, with lower levels observed during the wet season compared to the dry season. In contrast, indoor NO2 concentration levels in the kitchen were markedly lower during the dry season than in the wet season. The lowest pollutant concentration levels were recorded in the bedroom; however, these minimum values still exceeded the maximum concentration levels recommended for humans by the WHO, ASHRAE, and other IAQ regulatory bodies. Thus, this study provides insight into the variation in pollutant dispersion across seasons in mud houses. The findings will support the formulation of policies to improve indoor air quality and enhance building designs for rural dwellers.