BR initially numbered departmental stock inherited at nationalisation with a regional prefix (eg DE, DM, DS or DW). From 1967 this became DB regardless of region. A prefix could also be allocated to indicate the use of the vehicle, for example ‘A’ represented Mechanical & Electrical Engineers. Thus during its later use as a breakdown tool van, [[GWR 5804 Brake Third]] became ADW150304.
[[TOPS codes]] for Departmental vehicles were in the ranges:<br>
*Yxx: Departmental bogie wagons
*Zxx: Departmental two-axle carriage or wagon
==Internal User vehicles==