For the last few years, road and railway tunnels have to comply with a growing number of rules in terms of passenger safety. These increasing safety requirements demand new electro-mechanic (E+M) systems to be installed inside the tunnels.At the same time, the tunnel owners and operators are asking for reliable and cost optimized electro-mechanic installations. The only way to satisfy both demands simultaneously is by designing very efficient systems with highly integrated and standardized components. ZITRÓN has contributed to achieving this objective by developing a standardized modular solution for tunnel cross passages. It consists of pre-fabricated structures, where the access doors and all the different systems to be installed in the tunnel cross passages are integrated.