Answer to Question #11184 Submitted to "Ask the Experts"

Category: Medical and Dental Equipment/Shielding — Lead Aprons

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

Q

During medical imaging procedures, why is a lead vest worn from the neck to below the reproductive organs? Why is it not necessary to protect from the neck up?

A

That is an excellent question, and the answer is rather simple. There are no lead aprons on the market that cover the head simply because you cannot see through them. Ideally, the lead apron would cover the entire body; however, covering the head is not practical with typical lead aprons. Compared to the torso, there are no critical organs in the arms and legs, except for bone marrow production in the bones. The femurs in the upper legs produce a significant portion of the bone marrow, and lead aprons typically cover down to the knees. Many lead aprons also include a built-in flap to cover the thyroid in the neck. Typical lead aprons, then, cover all critical organs except for the lens of the eyes. Leaded glasses are available to protect the eyes and are typically used in x-ray rooms where radiation doses tend to be the highest (interventional radiology and cardiac catheterization laboratories).

There is at least one product on the market that is made to cover the entire body down to at least the knees. It consists of a suspended lead apron with a lead glass shield on top. The user stands behind this device and can see through the top and is able to move around with the device in front of him or her.

Kennith "Duke" Lovins, CHP 

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 2 March 2015. 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.