Explanation of Individual Exposure History

Information in this report is required by state and federal regulations and contains data for the NRC Form 5 and other equivalent forms. This report is for the individual to keep. The Radiation Safety Office keeps a copy of this report on file.


Explanation of Annual Form

Sections of Form 5 that do not apply to a participant will be blank. Annual Form 5 report doses are in rem , while monthly reports are shown in mrem. To convert Form 5 doses to mrem, multiply the dose in rem by 1000.


External Doses

External dosimetry - whole body (Luxel) and extremities (rings). Doses will be left blank when all dosimeters issued for the year were unused or unreturned.

"ND" = not detectable. This indicates that a dosimeter(s) was issued but did not record any dose, meaning the dose was much lower than natural background radiation, which is about 300 mrem per year.

Item No. Description
Item 11. Deep Dose Equivalent (DDE) - dose at a depth of 1 cm in tissue recorded by film badge.
Item 12. Eye Dose Equivalent To The Lens Of The Eye (LDE) - dose at a depth of 0.3 cm in tissue (approximately the depth of the lens of the eye) recorded by the whole body dosimeter.
Item 13. Shallow Dose Equivalent (SDE, WB) - dose at a depth of 0.007 cm in tissue (the approximate thickness of the outer protective layer of skin (stratum corneum)) recorded by the whole body dosimeter.
Item 14. Shallow Dose Equivalent (SDE, ME) - dose at a depth of 0.007 cm in tissue, as recorded by a ring badge (if applicable).
Item 15. Committed Effective Dose Equivalent (CEDE) - whole body dose for the amount of radioactive material in Item 10D.
Item 16. Committed Dose Equivalent, Maximally Exposed Organ (CDE) - largest dose to any organ from the intake.
Item 17. Total Effective Dose Equivalent (TEDE) - internal dose and external dose combined.
Item 18. Total Organ Dose Equivalent, Max Organ (TODE) - external "whole body" dose plus the maximum organ dose for the internally deposited radionuclide (if applicable).

If you have questions regarding your external exposure call the Radiation Safety Office at 206.543.0463 or email radsaf@u.washington.edu .

Comments

Item No. Description
Item 19. Contains the Landauer summary of all UW Landauer dosimeters for all years prior to and including the reported year. Does not include history from other employers or dosimetry companies.

Intakes

Internal dosimetry - bioassay (thyroid count or urinalysis). Evaluated for individuals working with relatively large quantities of radioactive iodine in liquid form. Involves thyroid counts using a sensitive detector held in front of the neck, and measures any radioactive materials inhaled or ingested. Unless an individual worked directly with millicurie quantities of radioactive iodine, these sections of the form will be blank.

Item No. Description
Item 10A. Radionuclide
Item 10B. Class - an assumption about the chemical behavior of the radioactive material inside the body.
Item 10C. Mode - usually "H" (inhalation).
Item 10D. Intake - an estimate of the amount of radioactive material inhaled or ingested. (Applies only to bioassays)

If you have questions regarding bioassays call the Radiation Safety Office at 206.543.0463 or email radsaf@u.washington.edu .


Questions

If you have any further questions or would like an in-service presentation on radiation safety or dosimetry service, please call the Radiation Safety Office at 206.543.0463 or email radsaf@u.washington.edu .


Signature Block


Item No. Description
Item 20. Signature Licensee - The signature block is included for NRC licensees. However, the UW is licensed through the State of Washington. As such, this NRC Form 5 does not need to be signed nor returned.

State and Federal Standards for Exposure to Radiation

Occupational Dose Limits*

(Different tissues have different sensitivities, and therefore different dose limits.)

Dose Category Annual Limit in mrem Annual Limit in rem
Deep Dose Equivalent 5,000 5.0
Lens Dose Equivalent 15,000 15.0
Shallow Dose Equivalent 50,000 50.0
Extremities 50,000 50.0

*Well below the thresholds for any observable health effects from radiation.
* Yield an occupational risk that is comparable to other light industries.

Comparison

  • An individual receives approximately 300 mrem per year from natural background radiation which includes natural sources, such as cosmic rays, and naturally occurring radioactive materials.
  • Control dosimeters are used to subtract the signal from natural background radiation, so that it is not included as part of your occupational dose.
  • Average Occupational dose for workers in the nuclear industry is 450 mrem per year.