摘要：The study investigated the emission of Hydrocarbons (HC), Oxides of Nitrogen (NOx), Carbon monoxide (CO) and Carbon dioxide (CO2) in vehicles. The study adopted a multiple research design approach to select five cities, garages and vehicles for the study. Whilst the cities were purposefully selected, the garages or fitting shops were selected by first identifying a garage owner who then introduces the researcher to another garage. This approach continued until the 200 targeted vehicles were reached. Two hundred vehicles used for the study were randomly selected as owners of vehicles visited the fitting shops for regular maintenance of their vehicles. The data was analyzed using analysis of variance (ANOVA) to compare the emission of various gasses. The study revealed that diesel vehicles emissions at 34.1 km/hr were considerably reduced when compared with EURO-6. At this speed CO emission was 0.01 g/km and lower than the standard level of 0.50 g/km. Oxides of Nitrogen (NOx) emissions of 2.3g/km was higher than the EURO-6 standard of 0.08g/km. Hydrogen Carbons (HC) emission of 0.65g/km was higher than EURO-6 standard of 0.17g/km. It is recommended that advanced technologies with no or little gaseous emissions must be adopted by vehicular manufacturing nations to curb or reduce the emission of harmful gases that leads to global warming.
