Answer to Question #9586 Submitted to "Ask the Experts"

Category: Medical and Dental Equipment/Shielding — Shielding

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

I'm going to perform a radiation survey for a clinic where the height of the walls between the dental x-ray rooms is about 2.1 m; beyond this height is a void (an empty space). What is the maximum recommended height of the separation of walls between dental x-ray rooms? Is it acceptable to have such a design as long as it is recommended by the manufacturer? Regarding the sky-shine effect, is it neglected in this case?

From the National Council on Radiation Protection and Measurements (NCRP) Report No. 147, Structural Shielding Design for Medical X-Ray Imaging Facilities, "Although floor-to-floor height will range from 3 to 5 m, protective shielding need normally extend only to a height of 2.1 m above the floor, unless additional shielding is required in the ceiling directly above the x-ray room." (NCRP, p. 21). This will also apply to dental installations. While it is unlikely that shielding will have to extend above this height for a dental installation, you should still obtain the services of a qualified radiation expert to make an accurate determination for your application.

Ken "Duke" Lovins, MS, CHP

Answer posted on 8 March 2011. 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.