Dosimetry

What is a dosimeter?

A radiation dosimeter, also known as a radiation badge, is a wearable device that measures the amount of ionizing radiation an individual has been exposed to. There are many facilities that may require individuals who work with or near to sources of ionizing radiation to wear personal dosimetry including medical, dental, veterinary and research facilities. Some facilities are better served by using area monitors which track the exposure in a given location rather than an individual.

Who needs dosimetry?

The Nuclear Regulatory Commission (NRC) and the Minnesota Department of Health (MDH) both require individuals who use sources of ionizing radiation be monitored for radiation exposure if their potential for exposure from external and/or internal radiation sources exceed certain levels. These levels are currently 10% of the annual occupational dose limits.

The Department of Radiation Safety (DRS) reviews each research and medical protocol that involves the use of ionizing radiation and assesses dosimetry needs on an individual basis.

What to do if you are required to wear a dosimeter? 

Individuals who are required to be monitored must do the following before using radiation sources:

  • Complete the Dosimetry Request Form to obtain the required dosimetry needed.
  • Wait to begin your work with ionizing radiation until your receive your permanent dosimeter(s). If you are unable to wait for the arrival of your permanent dosimeter, you may request a temporary dosimeter by selecting the option on the initial request form or by contacting DRS.
  • Complete any applicable radiation safety and operations training.
  • Wear the required dosimeter(s) any time you are handling radioactive material or will be potentially exposed to ionizing radiation while on the job.
  • Contact DRS with any other questions at [email protected].

NOTE: If you are assigned a dosimeter, it is required by state and federal rules to wear it while using radioactive materials

How to care for your dosimeter?

  • Store the dosimeter(s) in a designated work site area away from radiation sources and excessive heat and/or moisture.
  • Do not take a dosimeter home or wear it during non-job related radiation exposures such as medical or dental x-ray examinations.
  • Do not intentionally expose the dosimeter to a radiation source, or damage it in any way.
  • It is the responsibility of the wearer to exchange their dosimeter(s) during the designated exchange period. Information on the time periods for exchanging dosimeters will be provided when a dosimeter is issued.
  • Immediately inform your supervisor and/or DRS if your dosimeter has become lost, damaged, or misplaced. We will issue a temporary replacement as soon as possible.

REMEMBER: Personnel dosimeters do not protect an individual from ionizing radiation. Dosimeters only record the radiation dose an individual has accumulated.