Physics Corner #6: Care and feeding of radiation badges

Physics Corner was a series of articles I wrote for an incarnation of the department newsletter between 2000 - 2001. They're collected here for posterity and maybe to provoke me into starting it up again as an online column.

If you're following, you might be wondering what happened to #5. Physics Corner #5 was an unfinished article on quality control for diagnostic quality monitors. I may get around to finishing it one of these days.

Care and feeding of radiation badges

There always seems to be confusion over where and how to wear film/radiation badges. Employers are required by law to track radiation doses for any employee that may potentially receive at least 10% of the maximum annual permissible dose of 5 rem/year. This is why radiation badges are issued.

The type of radiation badge being issued to MUSC employees contains a relatively new type of material that is significantly more sensitive than the traditional film badge and can record exposures as low as 1 mrem. Film badges are limited to a minimum detectable exposure of 10 mrem.

So, how do you wear the badge properly?

Most radiation workers are issued only one badge. This badge should always be worn on the torso area between the neck and waist. If a lead apron is worn, the badge is worn on the outside. Don't forget to take the badge with you after you're finished with the apron!

In some areas, usually in interventional radiology and cardiology, employees are issued two badges. Both badges are worn on the torso area again, with one badge worn underneath the apron while the other is worn outside the apron. The badges will indicate where each one should be worn.

Employees working with radioactive materials are generally issued one regular badge and one ring badge. The regular badge is worn on the torso area, while the ring badge should be worn with the white ID section facing the surface receiving the highest exposure. For example, if you're working in the hotlab preparing a dose, the ID section should be worn on the palm side of the hand. Out in the clinic after the patient has been injected, the ID section should be turned around to face the outside.

Pregnant workers who have declared their pregnancy to the Radiation Safety Office are issued a second badge to monitor the radiation exposure to the fetus. The second badge is worn under the apron at the waist.

Badges should be changed on a monthly basis, and should be stored in a radiation free area when not in use.