They are safer without them

When an accident occurs as terrible as the one experienced this Sunday with the crash between two trains in Adamuz, CórdobaAfter the initial impact, the questions begin. How this could have happened is one of the first, but also how the damage could have been minimized. The normal thing is to apply the logic of everyday life and what we have closest at hand: the car security systems. And that’s where the question arises as to why trains don’t have seat belts.

The answer is that the cure would be worse than the disease.

what has happened. Occurred On the afternoon of January 18: an Iryo train that left Malaga heading to Madrid derailed near the Cordoba municipality of Adamuz. It happened on a straight line and the last cars of the train were scattered along the track. However, an Alvia was traveling in the opposite direction, which collided with those Iryo cars, causing the derailment of the second train.

The victim count is not definitive, but according to emergency serviceswe are talking about 39 deaths, 173 slightly injured and 73 injured who required hospitalization.

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Prevent, do not restrain. After the terrible event, a question that is easy to come to mind is why we have a seat belt in any vehicle except on the train. The first thing is that the security philosophy of the railway focuses on avoiding accidents. There are multiple active systems, such as signaling communicated with switchboards to automate some sections and control speed, but also passive ones.

In the unlikely event of a collision due to the fact that they are vehicles that circulate on exclusive tracks, or in case they derail, high-speed trains incorporate crash energy management systems. It is a compendium of elements that are designed to minimize the impact force suffered inside the cabin:

• Highly deformable zones.
• Cabs and frames designed to absorb impact.

Furthermore, since they are so heavy, even if a violent deceleration is caused, the emergency braking system is usually below 1 m/s², which minimizes the risk of being thrown.

Theory. It is not all about trusting these prevention systems: studies have been done. A few years ago, the British Rail Safety & Standards Board concluded that, in a longitudinal collision, both two-point (airplane) and three-point (car) seat belts would increase the risk of injury to the passenger.

Apart from the systems mentioned, high-speed trains have seats designed to deform. Again: it serves so that, in the event of a crash, the seat is that last line of defense so that the passenger does not absorb the impact. If a belt were fitted, the seat would have to be more rigid, transmitting energy to the passenger’s knees, head and back in the event of an accident.

Practice. There is another question: If the carriage overturns or deforms, the passenger can be ‘tied’ with the belt, preventing them from seeking shelter or carrying out a quick evacuation. This aggravates the consequences of the accident and maximizes the difficulty at the time of extraction. But it’s not all theory.

In the Rail Safety & Standards Board study, six real accidents were analyzed and the conclusion was terrifying:

• The belts would have saved 11 lives by preventing expulsions.
• However, 88 victims would have been claimed by trapping passengers in the crushed areas in the cabin.

The conclusion was that it was a system that could do more harm than good. Also, due to the number of passengers who stand up during the journey, it would be difficult for everyone to wear it, aggravating the result in the event of a crash convert some in projectiles against others who are in their seats. In the British study also commented that those who do not use belts, when thrown and colliding with rigid seats that accommodate the belt system, would suffer more serious injuries than if they had collided with a standard deformable seat.

And on airplanes? It’s different. It’s okay that they go much faster and that, due to the characteristics of the environment, a seat belt seems more like a placebo than a real safety measure. However, on an airplane the seat belt has more sense if we take into account the type of vehicle movements. In the event of strong turbulence or decompression, the belt would act as it should, holding the passenger in his seat and preventing him from being thrown off or from a ‘boat’, potentially harming himself or those around him.

In the case of seat belts on the train, in the end it was a design decision between seat belts or deformable seats, since both are not compatible, relying on the low probability of an accident and the passive measures that the trains themselves incorporate.

Unfortunately, there are always exceptions.

Images | Robot8A, Daniel Schwen

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