Prognosis of Emission Limits and Regulations for Vehicular Emission Pollutants in Nigeria
The main purpose of this study is to propose a limit and regulation for vehicular emission in Nigeria using a prediction tool. Two (2) gas Analysers (the UEI – Automotive 5 gas fuel efficiency analyzer and Infrared Industries Inc – DC 5 gas analyzer) were used to measure concentrations of CO, CO2, HC, NOX, O2 and A/F Ratio from vehicular exhaust both in the idle and motion mode. The analyzer determines the Emission Factors (EFs) in gram per kilometer of pollutants based on distance covered and fuel consumption. EFs for both new and used vehicles are, at best, as good as EURO II. But EF for CO is 3 to 4 times that of EURO II. The determined EFs were used to calculate the Emission Inventory along a chosen corridor in Lagos Metropolis. A Simple Interactive Model is applied to estimate percentage reduction on emission from various six scenarios. Optimal reduction values are obtained when emission standards are changed from EURO II to EURO V, currently in vogue in India, Egypt and Brazil. Fuel switch from gas oil to CNG gives promising results. Emission standards based on EURO IV are proposed and methods of regulation and enforcement are discussed.