You're on the fourteenth floor of a prewar Manhattan office tower being gutted for a tech tenant. The plans say it's a straightforward interior demo — pull the walls, expose the slab, set new MEP. You step into what's drawn on the prints as a service alcove, and the floor underneath you fails. A concealed slab pocket — never disclosed by the owner, never noted in any survey — collapses with you on top of it. Steel decking pins your pelvis and femur against rebar. By the time