Answer to Question #10251 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:

Q

I work as a veterinary nurse and am currently exposed to approximately 24 x rays per week. While these x rays are occurring, I wear only a lead apron. We have no thyroid protectors or radiation badge readers available. I am right next to the x-ray machine, with my head and neck very close to (but out of) the main beam, due to the necessity of holding our patients in position. I have no way of measuring my exposure, and I am very worried about the effects this exposure may have on my health and cancer risks in the future. Have I anything to worry about?

A

It's unlikely you are approaching any levels of radiation dose that exceed regulatory limits and even more unlikely that you are approaching radiation doses that cause harmful effect.

It is difficult to estimate the radiation doses you might be receiving since you are not wearing any radiation exposure monitoring devices. These devices are required if a worker is expected to receive 10 percent of the annual radiation dose limit. You might want to inquire about whether devices should be worn or how it was determined that workers at your organization wouldn't receive 10 percent of the annual limit.

I can say, as long as you are wearing a lead apron, that your body is well protected since an apron generally stops greater than 90 percent of the x rays coming in contact with it. And, since you are not in the primary beam, it is very unlikely that any unprotected organs are receiving very much radiation dose.

I'm sorry I can't be more precise. I can share with you, however, that in a recent report by the National Council on Radiation Protection and Measurements (NCRP Report 160), it was shown that, out of nearly 300,000 monitored veterinary workers exposed to radiation, the average annual radiation dose was 0.28 mSv. To put that in perspective, a chest x ray delivers about 0.1 mSv to the patient, a CT scan about 10 mSv to the patient, and one year of natural background radiation is about 3 mSv.

The only way to know your personal exposure for sure is to wear a personal monitoring device.

Kelly Classic
Certified Medical Health Physicist

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 25 April 2012. 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.