Answer to Question #11455 Submitted to "Ask the Experts"

Category: Medical and Dental Patient Issues — Diagnostic X Ray and CT

The following question was answered by an expert in the appropriate field:


Can you be exposed to radiation if you walk by an x-ray machine or computed tomography (CT) scanner that is not in use? Sometimes the doors are open when the test isn't being performed, and people walk by the open doors. Does that pose any danger at all? Shouldn't the doors be closed at all times so that people walking by are not exposed to radiation?


X-ray machines and CT scanners do not produce radiation except when they are being used to take images.

Although you did not ask about magnetic resonance imaging (MRI) machines, the MRI magnet is always on even if a scan is not being performed. This is why no ferromagnetic material (material attracted by magnetic fields) is allowed in the MRI room at any time.

Kent Lambert, CHP

Answer posted on 29 March 2016. The information posted on this web page is intended as general reference information only. Specific facts and circumstances may affect the applicability of concepts, materials, and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice. To the best of our knowledge, answers are correct at the time they are posted. Be advised that over time, requirements could change, new data could be made available, and Internet links could change, affecting the correctness of the answers. Answers are the professional opinions of the expert responding to each question; they do not necessarily represent the position of the Health Physics Society.