The goal of wearing a dosimeter badge is to measure or estimate the radiation dose to organs not covered by the apron, such as eyes and the thyroid. It is best to place the badge outside of the lead apron, as it will be able to detect any radiation that passes through the apron. This is because aprons are effective at stopping most scattered X-rays. Areas where workers may be required to use personal dosimetry are: medical centers, dental centers, doctor's offices, and chiropractic offices. Keep in mind, local and national laws will help determine who needs to wear dosimeter devices. Manufacturing, mail rooms, mining and other areas may also require dosimeter badges and rings.
While dental centers and doctor's offices may not be required to provide dosimetry, it is still a good idea to use a film badge or TLD service as a permanent reference for documentation. The results should be reviewed and compared to regulatory standards and individual exposure histories. If a report is out of the ordinary (too high), then it is necessary to find out why the exposure is abnormal and correct the problem. The best way to determine the amount of exposure a person receives over an extended period of time is through the use of personal dosimetry.
If two clearly designated dosimeters (inside and outside) are assigned to a worker wearing an apron, one can be used inside the apron. The specified point is generally given by the position in which the person's dosimeter is worn and should NOT be used outside of their work or laboratory-related activities. Dosimeters DO NOT protect anyone from radiation exposure; they simply report the amount of radiation (if any) the user received. It is important to keep this in mind when wearing your dosimeter badge outside of your lead apron at collar level. Of course, always check with your RSO to get specific guidelines.
