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Safety of rail vehicles is an important feature of sustainable public transport. Proofs of an effort in that area are new recommendations and regulations from the expert commission (WG2 of the Technical Committee CEN / TC 256) regarding trams and light rail vehicles aimed at vulnerable road users. Additional requirements on tram safety can be requested by the vehicle operator and/or city. Pedestrian safety measures can be adopted from the automotive sector utilising the protection principles from Regulation EC No. 78/2009, ECE/UN regulations, and EuroNCAP tests. The purpose of this publication is to introduce a simplified testing method for the tram front end with respect to pedestrian head-on collisions. Testing methods based on segment impactors were generally accepted. The wrap-around distance defines the assessment of vehicle impact areas. A mathematical model was created to compare the results of the full-scale tests and the segment tests done by the standard and simplified aluminium head impactors. The tram front-end design can be tested using this alternate method, based on a simple impactor and easy methodology, providing an efficient tool to inspire both the tram manufacturers and vehicle operators to improve the vulnerable road users’ safety in city traffic.

As was shown in the previous part of the study, windshields are an important part of the passive safety means of modern low-floor trams with an extraordinary effect on pedestrian safety in a pedestrian–tram collisions. Therefore, maximum attention must be paid to the definition of tram windshield characteristics. This article describes a windshield crash test, from which data are obtained to verify the feasibility of the applied computational approaches. A developed analytical model is utilised for a simple description of the energy balance during collision with an illustrative definition of the important parameters of laminated glass as well as their clear physical interpretations. The finite element analysis (FEA) performed in Ansys software using two versions of material definition, namely a simpler (*MAT_ELASTIC with nonlocal failure criterion) and a more complex (*MAT_GLASS with brittle stress-state-dependent failure) material model, which are presented as suitable for obtaining a detailed description of the shattering process of laminated glass, which can also be used effectively in windshield engineering.

This article represents the first paper in a two-part series dealing with safety during tram–pedestrian collisions. This research is dedicated to the safety of trams for pedestrians during collisions and is motivated by the increased number of lethal cases. The first part of this paper includes an overview of tram face development from the earliest designs to the current ones in use and, at the same time, provides a synopsis and explanation of the technical context, including a link to current and forthcoming legislation. The historical design development can be characterised by three steps, from an almost vertical front face, to leaned and pointed shapes, to the current inclined low-edged windshield without a protruding coupler. However, since most major manufacturers now export their products worldwide and customisation is only of a technically insignificant nature, our conclusions are generalisable (supported by the example of Berlin). The most advantageous shape of the tram’s front, minimising the effects on pedestrians in all collision phases, has evolved rather spontaneously and was unprompted, and it is now being built into the European Commission regulations. The goal of the second part of this paper is to conduct a series of tram–pedestrian collisions with a focus on the frontal and side impacts using a crash test dummy (anthropomorphic test device—ATD). Four tram types approaching the collision at four different impact speeds (5 km/h, 10 km/h, 15 km/h, and 20 km/h) were used. The primary outcome variable was the resultant head acceleration. The risk and severity of possible head injuries were assessed using the head injury criterion (HIC15) and its linkage to the injury level on the Abbreviated Injury Scale (AIS). The results showed increasing head impacts with an increasing speed for all tram types and collision scenarios. Higher values of head acceleration were reached during the frontal impact (17–124 g) compared to the side one (2–84 g). The HIC15 values did not exceed the value of 300 for any experimental setting, and the probability of AIS4+ injuries did not exceed 10%. The outcomes of tram–pedestrian collisions can be influenced by the ATD’s position and orientation, the impact speed and front-end design of trams, and the site of initial contact.