Urban air pollution is increasingly getting attention in developing
countries in recent years. It was against this backdrop that this piece
of work examined three indices of air pollution along a single carriage
road (Kissy Road) and dual carriage road (Wilkinson Road) on either
direction. Brief monitoring spell of nitrogen dioxide (NO2); sulphur
dioxide (SO2) and carbon monoxide (CO) were made between August 2015 and
September 2015 using the Drager X am 5000 realtime monitor for the
different gases. Diurnal monitoring was made in the morning, afternoon
and evening periods representing peak and off peak periods. Results
indicated higher levels of pollution at Kissy Road relative to Wilkinson
Road. Considerable variation were also observed among the pollutants
for the two sites and the hourly average values revealed levels that are
within ambient air quality standards except for SO2. Field observations
revealed poorly maintained vehicles, human behavioral pattern, frequent
traffic jams were attributed to the observed values.
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This work was fully supported and financed by the Environment Protection Agency Sierra Leone (EPA-SL) as part of their periodic research into the environment.
The authors declare that they have no competing interests.
Special thanks again extended to the field assistants; Mr. Joe Milton
Beah, student at the Institute of Environmental Management and Quality
Control; Mr. James During who also provided security support during the