Estimation and measurement of the automobile pollution : application to Bejaia case

In this paper, we present the estimate and results of measurement of air pollution in Béjaia
city in Algeria.
We used an enclosure of 0,80 m3 for the collection of gases directly on the outlet side of the
tailpipe of the vehicles. A three-gas detector (MX21 plus), introduced inside the enclosure,
measures the rates of carbon monoxide CO, sulphur dioxide SO2 and nitric monoxide NO. We
studied the exhaust pollutants according to the age of the vehicle (1980 – 2004) and the
acceleration of the engine. Measurements related to a sample of 204 vehicles using gasoline
or diesel oil fuel.
The comparison between the rejections and the standards European, American and
Japanese norms encourages us to challenge the authorities on the urgency of the
introduction of the vehicle inspection and technical control. Except the new vehicles (less than
5 years old), where the results are comparable, the others exceed largely the standards.
We have counted the number of vehicles passing through the Daouadji square during one
month (March 2004) and calculated the total pollution rejected. The comparison with the air
pollution measured in situ confirmed that urban pollution is primarily from automobile sources.
On the curve of the weekly evolution of the air pollution the days and peak hours of the
automobile traffic appear clearly. The correlation with the number of vehicles is very
significant (0,78).
By taking account of the annual rate of increase in the number of vehicles and keeping the
current park without adequate maintenance, a statistical model envisages an unbearable
urban pollution near 2010.