As standard, the steps of industrial staircases are galvanised. Specific metal steps are an option: with mesh grids, sheet metal grids, etc.
For PAB staircases, the steps are normally wooden. The steps’ width is determined by the minimum width depending on the total number of people who are going to use it. This width is called "Unit of passage”.
A staircase without risers will be lighter in terms of architecture and design. But risers can be installed to avoid feet slipping between steps.
