Review of NCRP radiation dose limit for embryo and fetus in occupationally-exposed women

On the basis of the current review, the NCRP has decided to make no change in the current recommendation of its radiation dose limit to the unborn. The NCRP recommendation is restated here as follows: During the entire gestation period, the maximum permissible dose equivalent to the embryo-fetus from occupational exposure of the expectant mother should be 0.5 rem. Since the preparation of the 1971 report there has been no new evidence concerning teratogenic or carcinogenic effects of irradiation of the embryo-fetus that would justify a change in the limit in either direction. It is implicit in this position and recommendation that women who can reasonably be expected to be pregnant should not, in certain instances, be exposed to the same radiation environment as women who are not considered fertile or as men. This applies particularly to conditions where radiation workers can receive dose equivalents of 0.5 rem or more in short periods