The predecessor limits carpets and other soft flexible coverings on the path: pile height or thickness no more than 6 mm and backing no more than 4 mm; exposed edges fastened down with a trim along their full length; and leading edges of trims no taller than 3 mm with a vertical face or 5 mm with a rounded or bevelled face, any greater height being ramped at no steeper than 1 in 8. It also covered recessed matting, whose level difference is capped at the same 3 mm and 5 mm values; the 2021 contents list only carpets and soft flexible materials under 4.3.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.