Pedestrian level of service: the impact of social groups on pedestrian flow characteristics

A comprehensive measure of the level of pedestrian comfort can lead to an improved design of public spaces, to the appropriate dimensioning of urban infrastructure (such as airports, stations and commercial centers), and, most importantly, to a design that is more responsive to people and to that very fundamental human activity: walking. The planning and design of the pedestrian environment is based on pedestrian Levels of Service (LOS). These levels currently classify the level of comfort based on space available for movement and speed (and delay, in case of crosswalks). Guidance is provided for different area types and times of day. Although many methods of assessing pedestrian LOS have been developed, all these do not consider spontaneous pedestrian groups. However, social groups, such as friends, couples, colleagues and families, represent an important component of urban crowds. The paper presents first, an overview of the current methods for assessing pedestrian environment LOS. Then the paper presents the application of the HCM method for the evaluation of a selected site LOS. The calculation is based on collected measurements of pedestrian flow. Some critical issues and inconsistencies result. These have been reviewed and read taking into account the presence of groups in pedestrian flows.