On the night from 10 to 11 May 2026, SBB commissioned trackside derailment detectors at around ten locations on the approaches to the Gotthard Base Tunnel. They have been installed on a particularly sensitive section, namely before the portal cross-over points on the access lines to the Gotthard Base Tunnel. Both passenger and freight trains travel at high speed on this line, whereby "high-speed switches" enable cross-overs.

Derailment detectors are the only proven technology for detecting a derailment on the infrastructure side. Their aim is to prevent a collision between two trains in the unlikely event of a recurrence. However, derailment detectors cannot prevent derailments; this requires better maintenance of freight wagons and adapted liability law in railway freight traffic.

Following the derailment of a freight train in the Gotthard Base Tunnel, the Swiss Transportation Safety Investigation Board (STSB) found that the cause was a wheel fracture on a freight wagon. To prevent such incidents in future, cracks in wheels must be detected at an early stage.

SBB supports the conclusions of the STSB's final report on the derailment. It is convinced that the resulting measures will further enhance safety in international railway freight traffic.

The most important measure will be the introduction of significant improvements in freight wagon maintenance. The current situation is that if an accident is caused by a defect in a wagon, the railway undertaking (RU) transporting the wagon is liable, not the wagon keeper. Wagon keepers therefore have little incentive to invest more than the absolute minimum in wagon safety. Liability legislation must therefore be amended. SBB supports the requirements issued by the Federal Office of Transport (FOT) and advocates a fair allocation of risk in railway freight traffic, which is generally one of the safest modes of transport.

With the commissioning of the derailment detectors, the temporary speed restriction to 160 km/h around the two portal cross-overs on the approaches to the Gotthard Base Tunnel has been lifted. The restriction had been in place since the tunnel returned to operation in September 2024 and remained in force until the derailment detectors were commissioned. The speed reduction had no impact on passengers or on connections in Ticino or German-speaking Switzerland. However, it did reduce travel time reserves, for example for absorbing delays.