Foreign Structure Posted on 11th November 201531st August 2020 by ThePD (The Project Definition) A Foreign Structure is any type of metallic structure that is not intended as a part of a system under cathodic protection. Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window)Click to share on LinkedIn (Opens in new window) Related Posted in Technology and tagged corrosion. ThePD (The Project Definition) ThePD has been developing the Preferred Project Definitions based on the actual project execution and operation experiences and knowledge with the Project Language, and sharing with you daily basis.