The European Rail Traffic Management System, or ERTMS, ERTMS was introduced by the EU in 1992 as a means of creating a uniform system of command, control and coordination of rail traffic to allow for ‘‘interoperability’’ throughout EU territory. The ERTMS standard exists at three levels (ERTMS 1, 2 and 3) depending on use, each distinguished by the type of wayside and on-board equipment used and the manner in which this equipment communicates relevant data.