Transport and mobility result in a range of costs and benefits. Some of these are felt directly by transport users: the costs of petrol or a rail ticket, or the benefit of getting to work conveniently by car or train. By paying for fuel or a ticket, transport users assume a share of the costs that they cause. There are other costs, however. Although these are caused by mobility, they are not reflected in its price. These are known as external costs, and they are environmental and accident and health-related in nature. These costs are borne by third parties, by the general public, or by future generations.
A wide range of scientific disciplines is involved in determining transport-related damages and costs. For example, we know from medical studies how exhaust fumes and noise affect human health. From this, the nature and severity of the illness triggered by transport can be established. Expertise in environmental science is also needed, to quantify the negative impacts of pollutants or transport infrastructures on plant and animal species. Finally, the effects determined in this way must be quantified in monetary terms. A metric known as the ‘value of statistical life’, or VOSL, is an important factor when placing a financial value on damage to health. It expresses how much a society is willing to pay to prevent a death.
External benefits are the counterpoint to external costs. Certain mobility behaviours generate a benefit that extends beyond the personal benefit to the transport user concerned. This is particularly true of walking, where physical activity generates benefits to health which then have a positive effect on society as a whole: less illness and thus more productive workers, as well as lower healthcare and social security costs.
For optimum resource allocation within an economy, external costs and benefits should be internalised. In other words, they must be charged or credited to those who produce them.
Externe Effekte des Verkehrs 2015 - Aktualisierung der Berechnungen von Umwelt-, Unfall- und Gesundheitseffekten des Strassen-, Schienen-, Luft- und Schiffsverkehrs 2010 bis 2015 (PDF, 1 MB, 26.03.2019)Schlussbericht (überarbeitete Version)
External Effects of Transport 2010 (PDF, 10 MB, 17.12.2014)Monetising Environmental, Accident and Health-Related Effects (english abstract and summarised version).