radguide

31 Radiation for Radionuclide Users Regulatory Limits for Exposure of Declared Pregnant Workers Because of the increased susceptibility of the human embryo and fetus to damage from ionizing radiation, the National Council on Radiation Protection and Measurement (NCRP) recommends that the whole body radiation dose received by a female worker during the 9 months of her pregnancy not exceed 500 mrem (i.e., 10 percent of the normal annual occupational dose limits). The Nuclear Regulatory Commission has published Regulatory Guide 8.13 that details potential health risks of prenatal exposures and suggests precautions and options for the pregnant worker. The 10CFR20 and related state regulations have adopted the NCRP recommendations. These regulation allow a worker to voluntarily inform her employer, in writing , of her pregnancy and the estimated conception date. The “ Declaration of Pregnancy ” form is to be used to declare her pregnancy. A TEDE of 500 mrem must not be exceeded by the declared pregnant worker throughout her entire pregnancy. If the worker has received greater than 500 mrem since the conception date, but prior to her declaration, she may not receive a TEDE of more than 50 mrem for the duration of her pregnancy. The declared worker may, at any time, revoke her declaration of pregnancy.