The article explores the capacity of zero-emission urban public transport (PT) and proposes a standardised method for calculating it across different PT corridors (bus, tram, metro and urban railway). As the European Union (EU) tightens regulations on emissions, targeting also PT, cities are increasingly shifting to electric and hydrogen-powered vehicles. A significant challenge was the lack of a unified methodology to calculate the capacity of zero-emission vehicles, e.g., battery-powered buses carry fewer passengers than diesel ones due to weight restrictions. The article addresses this gap by creating capacity matrices for various vehicle types based on standardised assumptions. Vehicle capacity is calculated based on seating and standing space, with standing passenger space standardised to 0.2 m²/person (E Level of Service). A detailed rolling stock analysis shows how modern designs and floor layouts impact passenger space. Matrices were developed for each mode of transport, showing the number of transported passengers per hour depending on vehicle type and service frequency. The highest capacity is achieved by metro and urban railway systems (up to 95,000+ passengers/hour/direction), while buses offer the lowest (up to 7800 passengers/hour/direction). The authors recommend standardising calculation methods and integrating matrices into planning tools for urban PT corridors.

Traffic calming zones (TCZs) are increasingly being implemented in urban areas to enhance road safety, reduce vehicle speeds, and support sustainable mobility. However, their impact on public transport (PT) operations, particularly bus services, remains underexplored. This study examines the impact of classifying streets into TCZs on bus transport performance in Poland’s ten largest cities. Geospatial analysis and a custom R algorithm delineated areas suitable for TCZs based on road class and administrative category. GTFS data were analysed for almost 1000 bus lines to evaluate the overlap of their routes with TCZs. The findings reveal that in several cities, a significant portion of bus operations would run through TCZs, with the average route segment affected notably by city and zone classification methods. Differences in TCZ size and shape across cities were also statistically significant. This study concludes that although TCZs contribute to safer and more liveable urban environments, their influence on bus speeds, which can lead to changes in fuel or energy consumption, and route design must be carefully managed. Strategic planning is essential to find a balance between the benefits of traffic calming and the operational efficiency of PT. These insights offer valuable guidance for integrating TCZs into sustainable urban transport policy without compromising PT performance.