What is PD CEN/TR 17420 about?
PD CEN/TR 17420 describes passive safety measures to reduce the consequences of collisions with pedestrians. These measures provide the last means of protection when all other possibilities of preventing an accident have failed.
NOTE: The following measures to actively improve safety are not mentioned in PD CEN/TR 17420:
- Additional position lights
- Additional cameras
- Driver assistance systems
- Additional acoustic warning devices, etc.
- View of the driver/mirrors
- Consequences for pedestrian injuries due to secondary impact with infrastructure (side posts, Concrete ground, poles, trees, etc.).
NOTE: The recommendations of this technical report only apply to new vehicles.
Who is PD CEN/TR 17420 for?
PD CEN/TR 17420 on vehicle end design for trams and light rail vehicles is relevant to:
- Manufacturers of tram-train vehicles
- Electrical engineers
- Pedestrians
Why should you use PD CEN/TR 17420?
PD CEN/TR 17420 describes the front-end design of tram vehicles and light rail vehicles that enables a pedestrian’s body to be deflected rather than be run over during an impact.
The entire sequence of an impact can be divided into three phases. All three phases can cause severe injuries to the involved pedestrian.
Also, PD CEN/TR 17420 provides the reference collision scenarios with pedestrians that should be considered as:
- Type A: Collision with a passing pedestrian in the front area of the vehicle
- Type B: Collision with a lying pedestrian on the ground in front of the vehicle
Collision type A covers the effects of a primary impact and influences the effects of the downstream phases, as well as collision type B, which covers the tertiary impact.
The geometrical recommendations and numerical simulations of pedestrian impact scenarios are given in PD CEN/TR 17420 to demonstrate the ability of the front-end design to limit the risk of severe injuries and to encourage lateral ejection.
Pedestrian anti-crush mechanism (PACM) is described in order to provide full effectiveness, protruding elements under the chassis that should not injure the pedestrian before he reaches the mechanism including the information on its assessment and validation program to verify the PACM’s capabilities during a collision with a person.
Overall, PD CEN/TR 17420 allows you to design and manufacture tram-train vehicles by keeping in mind human collisions that can be prevented by following certain safety measures.
