Pedestrian access to tram-stops has been intensively researched to ensure maximum case of access irrespective of passenger disabilities.  Ergonomic studies by Cranfield Institute of Technology have established the layout features of the stops including two new types of tactile paving to locate the tram doors and define the platform edge, shallow approach ramps and differential coloured paving to indicate safe and unsafe areas.  This has set standard tram-stop layout to be adopted throughout the system but has created slight specific problems on-street due to lack of road width or adverse impacts on the threshold of adjacent premises.  In these cases specific solutions, such as lowering the highway rather than building up the platform on the foot-way, have been adopted.