Interior of an automatic train (line 9 of the Barcelona metro) where a TOLA is present.
Automatic Line Operation Technician (TOLA) is the name given to the technicians assigned to automatic subway lines (Automatic Train Operation). Although they operate without a driver, the automatic lines have a technician who has two main functions: the customer service and the recovery of the railway service in case of failure.
In Spain, they only exist in Barcelona, where they are present on lines L9, L10 and L11 of the Barcelona metro.
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