V skladu z Direktivo Sveta 91/440/EGS z dne 29. julija 1991 o razvoju železnic v Skupnosti fn morajo imeti prevozniki v železniškem prometu povečan dostop do železniških omrežij držav članic, kar zahteva interoperabilnost infrastrukture, opreme, voznega parka ter sistemov upravljanja in vodenja, vključno s strokovno usposobljenostjo, higienskimi in varnostnimi pogoji pri delu za tisto osebje, ki je potrebno za vodenje in vzdrževanje zadevnih podsistemov ter za izvajanje posameznih TSI.
Pursuant to Council Directive 91/440/EEC of 29 July 1991 on the development of the Community's railways(6), railway companies must have increased access to Member States' rail networks, which in turn requires the interoperability of infrastructure, equipment, rolling stock and systems of management and operation, including those staff qualifications and hygiene and safety conditions at work required for the operation and maintenance of the subsystems in question and for the implementation of each TSI.