Railways Abbreviations and Acronyms
-   NWZNorth West Zone
-   OCCOccupied
-   OCLOperational Communications Link
-   OCSOnegcontrol Switch
-   OCUOperator’s Controk Unit
-   OEOperating Expenditure
-   OETROutline Engineering Train Requirements
-   OFNOptical Fibre Network
-   OHLOverhead Line
-   OHNSOverhead Line Neutral Section
-   OLBIOff-Line Battery Inverter
-   OLEAROverhead Line Equipment Asset Register
-   OLEMIOverhead Line Equipment Master Index
-   OOROut of Round
-   OPEXOperating Expenditure
-   OPMOperational Planning Manager
-   OPUGOther Passengtr Upgrades
-   ORNOverlay Radio Network
-   OSGOperation Safety Group
-   OSGROrdnance Survey Grid Reference
Last updated: — Total entries: 691