Au cœur du "facteur humain" en crise par Urda: "Dans un système dégradé, nous sommes la dernière protection"

Spanish railway operator Adif operates nineteen traffic regulation and control centers distributed across the country, which function as the operational core of the national rail network. In Madrid, two such facilities manage distinct networks. The center at Chamartin directs conventional lines for suburban services, freight, and medium-distance travel. The facility at Atocha manages high-speed routes toward Seville and Antequera, as well as connections to Extremadura. This week, Transport Minister Oscar Puente identified operators at the Atocha center as one factor contributing to the tragedy in Urda, Toledo, which resulted in sixty-nine deaths. The internal structure of these centers divides railway lines into regulation bands, segments spanning multiple stations and installations. Each band is assigned to a centralized traffic control desk. At each desk, a single circulation officer works alone before several screens. One monitor displays the video graphic, a schematic of the tracks used to track trains and operate stations. A second screen runs Sitra software, plotting train movements with stops on one axis and time on another. The workstation includes two telephones, one for internal line communication and another for external management tasks such as contacting maintenance or drivers via corporate mobile phones. A radio telephone allows direct speech with train cabins. To authorize a train’s passage, the officer sets an itinerary, marking start and destination signals. The physical interlocking system then verifies the route is clear, moves switches, and determines signal aspects. Train presence is detected through track circuits; when steel axles close the electrical contact between rails, the segment turns red on the screen alongside the train number. On the Madrid-Seville line, the LZB system provides protection by indicating allowable distance and maximum speed. This system failed during the Urda collision. When LZB fails, the control center orders trains to switch to lateral signaling block mode via standardized text messages. Drivers then rely on side-of-track signals and adhere to a maximum speed of two hundred kilometers per hour under the lower-performance ASFA system. A former Madrid circulation worker described the regulatory texts governing these degraded operations as three hundred and fifty pages intended to be memorized. He noted that some messages are nearly identical, questioning a model lacking quick-reference guides similar to aviation checklists. Both the control operator and the driver must manually record these orders in large ring-bound logbooks. In such degraded situations, the human element serves as the final safety barrier. Staffing changes have become a point of contention within the sector. Prior to the pandemic, a wave of retirements among veteran railway workers occurred. These employees were replaced by younger staff aged twenty-one to thirty-one. While newer workers navigate computer systems more effectively, industry insiders claim they lack decision-making experience compared to previous generations. Former employees stated that older workers were required to know all procedures because they bore total responsibility. Current complaints highlight a shortage of experienced personnel available to mentor new hires in practical application. The shift has been attributed to increased automation, which reduced the need for comprehensive manual knowledge previously required of controllers.