Why is necessary to reduce the speed in urban areas to 30 KM/H?

Resumen

In Spain, on November 2020, a new law imposed that the generic speed limit on single carriageway two-lane roads is reduced from 50 km/h to 30 km/h. The changes in the general rules of traffic, proposed by the Spanish government, are a sample of the evolution, in the use of the shared space of the streets, and at the same time shows its sensitivity towards road safety. Traditionally, the objective of the regulation was to attend to the growing increase in the use of motor vehicles (mainly cars), and for this reason, it was the protagonist in most of the articles of the General Traffic Regulations. Today, in many cities, the car is no longer the protagonist and shares the space on the streets, not only with other motor vehicles as buses or motorcycles, but also with pedestrians, bicycles, electric pedal-assisted cycles (EPAC), personal mobility vehicle (PMV)... Pedestrian mobility is becoming more and more important every day but the number of pedestrians that died inside Spanish urban areas in road accidents is almost 50% of total urban areas road fatalities. In this sense, the mobility and road safety policies developed by local administrations have to focus on the objective of the reduction of accidents and their severity involving pedestrians and other vulnerable users in urban areas. This article collects studies and experiences in other countries that show the effects of reducing the speed of motor vehicles in urban areas in order to reduce accidents and/or their severity if they occur. It also analyzes other options that reinforce this measure and that could help reduce this problem.