Answer to Question #13856 Submitted to "Ask the Experts"

Category: Medical and Dental Patient Issues — Worker Issues

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


I am a radiology resident. Today, during a fluoroscopy procedure, I put on lead covering my pelvis and thyroid area, but completely forgot to put on lead covering my chest/abdomen. The patient exposure was about 300 mGy. I was standing to the side of the patient next to the C-Arm. The C-Arm was pointing towards the floor. I am in disbelief I could do something so absentminded and have been worried sick all day. How concerned I should be?


I understand how you can be concerned over something that was avoidable, but you are certainly not the first resident (or the last) to have this happen. First, let me allay your concern—your exposure to radiation was most likely still fairly low even though the patient was exposed to 300 mGy. You were exposed to scatter radiation from the patient which is far less than what he or she received, and your distance from the patient was also a factor in reducing your exposure. Although I cannot state explicitly what your exposure was, because I don't know your specific details, I can make some simplifying assumptions based on known factors. As a general rule of thumb, the exposure at a distance of 1 meter (m) from a patient undergoing fluoroscopy is approximately 0.1% of what the patient received. If you were less than 1 m from the patient, your dose was slightly higher, and if you were further away, your dose was slightly lower. If you were 2 m or more from the patient, your exposure was likely very low. Using the information you provided and the rule of thumb described above, your exposure may have been about 0.3 mGy. To put this into perspective, a dose of 0.3 mGy is the same as about three chest x rays and is considered very low. 

I wish you the best of luck in your studies and your future as a radiologist!

Christopher B Martel, PhD, DABHP

Ask the Experts is posting answers using only SI (the International System of Units) in accordance with international practice. To convert these to traditional units we have prepared a conversion table. You can also view a diagram to help put the radiation information presented in this question and answer in perspective. Explanations of radiation terms can be found here.
Answer posted on 24 February 2021. 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.