Air pollutant emissions and acoustic performance of hot mix asphalts

This paper presents a study aiming at assessing the air pollutant and noise emissions of asphalt pavements. Four types of asphalt mixtures commonly used in Hong Kong were studied in the laboratory and field. Temperature was found to be the most critical factor affecting pollutant emissions. The volatile organic compounds (VOCs), particulate matter 2.5 μm (PM2.5) and polycyclic aromatic hydrocarbons (PAHs) concentrations varied in accordance with the types of mixtures. The stone mastic asphalt with a nominal aggregate size of 10 mm (SMA10) produced the highest total VOCs, while the polymer modified friction course (PMFC) had the lowest. The polymer modified stone mastic asphalt with a nominal aggregate size of 6 mm (PMSMA6) emitted the most PM2.5 of 114.2 μg/m3. PAHs were well below the health warning level of 200,000 ng/m3. The PMSMA6 was the quietest road surface.