Equipment envelope for hopper wagon

The present invention relates to an equipment envelope (10) for a hopper wagon. The equipment envelope comprises a housing (11) that is configured to define an enclosed cavity storage space (12) in a bulk commodities storage chamber of a hopper wagon body, in which hopper wagon control means and/or other component parts of the hopper wagon (30) can be housed for use. The equipment envelope may be configured to be arranged in the chamber such that it is located above a hopper wagon bogie (40), preferably adjacent a closable outlet. The equipment envelope may comprise a first end wall (111) that is configured to extend at a predetermined incline angle a towards the outlet. Depending on the configuration of the hopper wagon, the equipment housing may be configured to be located adjacent a further or alternative closable outlet. The equipment envelope may comprise a second end wall (112) that is configured to extend at a predetermined incline angle β towards the further outlet. The first end wall and second end may be configured to meet at an apex (14) such that the equipment envelope has a cross- sectional profile of a triangle, preferably a scalene triangle. A further aspect of the present invention relates to a hopper wagon comprising at least one equipment envelope.