immediately submerged in water, the design can feel less sanitary to modern users.
As a result, most contemporary toilets now employ “wash-down” or “siphonic” designs featuring smooth, sloped bowls that guide waste directly into the trapway—faster, cleaner, and more efficient.
Regional and Historical Context
Europe: Shelf-style toilets remain in use in some countries, particularly in public restrooms, due to longstanding plumbing standards or water-conservation priorities.
United States: Following the 1994 Energy Policy Act, which mandated low-flow fixtures, innovation shifted toward powerful, shelf-free bowl designs that maximize flush efficiency with minimal
