Health Physics Posted on 15th November 20154th September 2020 by ThePD (The Project Definition) Health Physics is the branch of radiological science dealing with the protection of personnel from the harmful effect of ionizing radiation. 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 HSE and tagged science. 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.