“Underwater shelf” means a flat, shallow area of a pool that adjoins the pool wall below the surface of the water, typically used for lounging, sitting, and playing in shallow water. The term includes “swim-out”, “sun shelf”, “Baja shelf”, “tanning ledge”, and “tanning shelf”.

Source. #13198, eff 5-1-21 (see Revision Note #3 at chapter heading for Env-Wq 1100)