Air Quality

The quality and purity of air is vitally important to the health and wellbeing of the population, particularly in urban areas. All sectors need to contribute to help reduce the level of ambient air pollutants and road traffic will continue to make important contributions as part of an integrated and coordinated approach dealing with both air emissions and greenhouse gas emissions.

Road transport has made huge progress in recent years and continues to make significant advances. The implementation of advanced engine technology, advanced exhaust after-treatment systems and cleaner petrol and diesel fuel has helped slash pollutant emissions from cars, vans, trucks and buses, leading to huge improvements in overall air quality in urban areas.

Exhaust pollutants from road transport are now a fraction of what they were two decades ago. Engine efficiency improvements and exhaust after-treatment systems have brought about massive reductions in carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NOx), particulate matter (PM) and ultra-fine particles (PN) from cars, vans and heavy commercial vehicles:

• The most advanced trucks now emit 86% less NOx and 95% less particulate matter than those trucks from the early 1990s.
• Over the past 10 years, truck exhaust emissions have reduced by 35% despite an increase in ‘work done’ (measured in tonne-km) by 30%.

Modern road vehicles with diesel engines use highly efficient particle filters that remove well over 99% of all particles formed in the combustion process (by number or mass), resulting in an exhaust particle content that is comparable, sometimes even cleaner, than the ambient air.