For a declared pregnant worker who chooses to continue work involving occupational exposure:
The dose limit for the embryo/fetus from conception to birth (entire gestation period) as a result of the
occupational exposure of the declared pregnant worker is 500 millirem [see 835.206(a)]. The dose to the
embryo/fetus is equal to the sum of doses received from external doses, sources inside the mother, and sources
inside the embryo/fetus.
Measures shall be taken to avoid substantial variation above the uniform exposure rate necessary to meet the
500 millirem limit for the gestation period [see 835.206(b)]. Efforts should be made to avoid exceeding 50
millirem per month to the declared pregnant worker.
If the dose to the embryo/fetus is determined to have already exceeded 500 millirem when a worker notifies her
employer of her pregnancy, the worker shall not be assigned to tasks where additional occupational radiation
exposure is likely during the remainder of the gestation period [see 835.206(c)].
Table 2-1 Summary of Occupational Dose Limits
TYPE OF EXPOSURE
General Employee: Whole Body (internal + external) (TEDE) [see 835.202(a)(1)]
General Employee: Lens of the Eye (external) [see 835.202(a)(3)]
General Employee: Skin and extremities (external shallow dose) [see 835.202(a)(4)]
General Employee: Any organ or tissue (other than lens of eye) (internal + external)
Declared Pregnant Worker: Embryo/Fetus (internal + external) [see 835.206(a)]
Minors: Whole Body (internal + external) (TEDE) [see 835.207]
10% of General
Minors: Lens of the eye, skin, and extremities [see 835.207]
The weighting factors in Appendix 2B shall be used in converting organ dose equivalent to effective dose equivalent for the whole body dose
The annual limit of dose to "any organ or tissue" is based on the committed dose equivalent to that organ or tissue resulting from internally
deposited radionuclides over a 50-year period after intake plus any deep dose equivalent to that organ from external exposures during the
Exposures due to background radiation, as a patient undergoing therapeutic and diagnostic medical procedures, and participation as a subject in
medical research programs shall not be included in either personnel radiation dose records or assessment of dose against the limits in this Table
See Appendix 2C for guidance on non-uniform exposure of the skin.
Whole body dose (TEDE) = effective dose equivalent from external exposures + committed effective dose equivalent from internal exposures
Lens of the eye dose equivalent = dose equivalent from external exposure determined at a tissue depth of 0.3 cm [see 835.2(a)].
Shallow dose equivalent = dose equivalent from external exposure determined at a tissue depth of 0.007 cm [see 835.2(a)].