Estimating the Key Factors Contributing to Vehicular Exhaust Emission in Ghana

The study examined the factors that contribute significantly to automobile exhaust pollution in the major city of Ghana, Accra. Using an SV-5Q automobile exhaust-gas analyzer, the concentrations of carbon dioxide (CO₂), hydrocarbon (HC), carbon monoxide (CO), and nitrogen oxides (NO_x) were measured on 1002 light-duty gasoline automobiles taking into consideration age, maintenance, and emission technology (catalytic converters). To achieve the aim of the study, the emissions data gathered were analyzed against the vehicle parameters (Age of the vehicle, Frequency of maintenance, and Emission technology). The significant parameters explained variance of 42%, 22%, 32%, and 7% in CO, CO₂, HC, and NO_x, respectively. The results showed that the age of a vehicle is a significant positive predictor of CO, CO₂, and HC emission but has no significant effect on NO_x. The result further shows that the frequency of maintenance negatively predicted HC emissions with no significant effect on CO, CO₂, and NO_x. The results also demonstrated that emission technology was consistently negatively related to CO, CO₂, HC, and NO_x. Finally, the result established that an increase in vehicle age increases the emission level, while regular vehicle maintenance, two-way and three-way catalytic converters fitted on vehicle exhaust system decrease the exhaust emission level.