An unenclosed shower is Type 1 where it has a frameless screen (unless the screen carries seals and deflectors that control spread) or is a shower over a bath with a fixed glass screen up to 900 mm. It is Type 2 where the shower has a curtain, is a shower over a bath with a curtain, has no curtain at all, or has a screen on one side only with an open entry through which spray can still escape. An unenclosed shower must not adjoin a Category 3 area, and such showers are unsuitable directly beside exits from the wet area (see 4.8.5).
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.