Dosimetry

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 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:

  • Contact the Department of Radiation Safety to obtain a dosimeter request card at rpd@umn.edu. 
  • Wait to receive your dosimeter(s)
  • Complete applicable radiation safety and operations training 
  • Wear the required dosimeter at any time you are handling radioactive material or will be potentially exposed to ionizing radiation while on the job

Note: It is against state and federal rules not to wear a dosimeter if you are issued one.

Fact: Most individuals don't need to be monitored because their potential for exposure is extremely low.

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 change his or her dosimeter during the designated change period. Information on the time periods for changing dosimeters will be provided when a dosimeter is issued. 
  • Immediately inform your supervisor and/or the Department of Radiation Safety if you have lost or misplaced your dosimeter (we need to issue a temporary replacement as soon as possible).

REMEMBER! Personnel dosimeters do not protect an individual from the effects of radiation, but only record the radiation dose an individual has accumulated.