Grates on the path must have circular openings no more than 13 mm in diameter and slotted openings no more than 13 mm wide and 150 mm long, set with the long side across the main direction of travel. Linear openings must also run transverse (at 90 degrees) to the main direction of travel unless they are narrower than 8 mm, when orientation is free. The 150 mm slot length limit and the linear opening provision are new in 2021.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.