Seat belts are now commonplace in cars and airplanes, but why aren’t they found on board trains? The question arises whenever one occurs railway tragedy like the one in Andalusia: among other things, in Spain itself, the fourth train accident in just 4 dayswith a train hitting a crane causing a couple of minor injuries.
In reality, the absence of seat belts on trains is not linked to savings or a design oversight, but it is a precise strategy of safety engineering.
The first thing to consider, in fact, is the physics of the vehicle: in most railway accidents the deceleration it’s much more gradual compared to that of a car, thanks to the enormous mass of the train. Furthermore, the very nature of train travel requires many passengers to be standing or moving.
As also highlighted in a study on the topic published on Oxford Academic in 2022, to ensure real safety it should be used 3-point seat belts (like those of cars). However, these would require seats extremely rigid And reinforced anchors to the floor. If an unrestrained or standing passenger were to hit one of these reinforced seats during an impact they would suffer much more serious injuries compared to those caused by a traditional seat, which it is designed for deform.
So what is the solution? There compartmentalization. This system requires that the interior of the wagon is designed as a “shell“protective: the seats have high backrests, are positioned at calculated distances and are built with materials capable of absorbing energy. In the event of a collision, the passenger is projected forwardbut the shock comes amortized by the controlled deformation of the seat in front, drastically reducing the risk of fatal trauma.the
Another fundamental pillar is the management of “survival space“. While in the car the seat belt serves to keep you in place, in the train it is essential that the passenger can be “free” not to remain anchored to a structure that could collapse. If the carriage undergoes structural deformation, a passenger strapped into the seat would be crushed along with it; without a seat belt, he is instead more likely to be moved to an area of the carriage that has remained intact.
Added to this is the passive safety of the structure: The ends of the carriages are designed to crumple and dissipate energy, preserving the integrity of the central passenger compartment.
Finally, the use of seat belts it would complicate rapid evacuation in case of emergency, especially if the train structure were to deform, blocking the seat belts. For these same reasons, the airbags: in an environment where the positions of the passengers are not fixed and predictable, their operation would risk causing more harm than good.
