A Quantitative Approach to Estimate the Damage Inflicted by Traffic Pollution on Historic Buildings in Al-Salt City, Jordan

Abstract

Traffic in the city of Al-Salt is not only putting pedestrians at risk and threatening the health of citizens, it is also damaging the town's historic buildings. Most stone buildings in the heritage-rich city are suffering adverse effects from vehicle-related pollution. This effect is highly visible soiling and discoloration from deposited carbon particles in the form of fine soot on most buildings. The level and progress of the damage depends on the geology of the stone and the proximity of the structure from traffic congestion. The accumulation of soot leads to the buildup of black sulfate (gypsum) skins on the limestone facade which causes the sound stone behind it to disintegrate. It is vital to the well-being of this historic treasure that the volume of the city traffic must be reduced and traffic flow improved. The main objective of this study is to qualitatively and quantitatively assess the damage caused to buildings of historical and cultural value by traffic pollution. Age of vehicles running on city’s streets and the rate of their emissions are quantified and analyzed. Several field investigations and laboratory tests were conducted to identify the chemical relations between pollutants and stone decay on these buildings.

Keywords: Traffic pollution, tailpipe emission, vehicular emission, historic buildings, limestone