The external steel staircase provides access to the new training classrooms in the renovated annex and also serves as an emergency escape route for the main building. The staircase is composed of solid steel square and rectangular sections. At ground level, the structure is supported by a single concrete plinth. In order to avoid obstructions within the escape route, the structural concept consists of a truss girder that spans the full distance from the concrete plinth to the main building in a single span. Elsewhere, the staircase is suspended from the existing annex; however, this configuration required the integration of beams and tension members to prevent tearing or pull-out of the façade structure.