Real Standing Capacity of Public Transport Vehicles: Area-Differentiated Passenger Densities at the Behavioural Capacity Limit—The Case of Vienna

The standing capacity of public transport vehicles is usually derived from flat area assumptions of four to 6.7 passengers per square metre (P/m2) or from structural load assumptions, while empirical values from regular service are lacking. This study determines real standing densities from 227 structured observations of stopping events in the Vienna metro, tram, bus and suburban rail network; in 126 of these, waiting passengers were left behind although space was still geometrically available (limit capacity). Densities were recorded separately for the door, aisle and transition areas of nine vehicle types and compared with field experiments with test persons. At limit capacity, mean densities were 3.19 P/m2 (door area), 2.37 P/m2 (aisle area) and 2.30 P/m2 (transition area), differing systematically with the accessibility of the areas. Service disruptions raised the door area densities to about 3.3 P/m2 and major events to around 4 P/m2; the experimental maximum occupancy reached 4.0 to 4.4 P/m2 without luggage and up to 40% less with luggage. Regulatory and manufacturer values were practically never reached in Vienna. Capacity figures for procurement, service planning and simulation should therefore use area-differentiated, empirically calibrated densities—about 3 P/m2 in door areas and 2.3 P/m2 in aisle and transition areas—instead of a single flat value.