Theory and practice of establishing radiation standards before and after the Chernobyl accident

If the external gamma dose to the whole body or exposure of the thyroid gland does not exceed 0.25 Gy, there is no need to adopt emergency measures which would temporarily disrupt the life of the population. If external exposure exceeds these levels but does not exceed 0.75 Gy, or if the dose to the thyroid gland from 131I exceeds 2.5 Gy, then ad hoc decisions have to be taken in accordance with the actual circumstances encountered. Doses of less than 0.25 Gy are virtually harmless to the individual, a dose of 0.25 Gy is considered potentially dangerous, and at doses of 0.75 Gy for whole-body exposure or 2.5 Gy for local exposure of the thyroid gland, radiation sickness or pathological changes in the gland may occur in some cases. External exposure doses to the population in the most severely contaminated regions of the Ukraine during the first year after the accident lay in the range 0.7-2.5 rem, and internal exposure doses - assessed from the results of 52,000 examinations - did not exceed 1 rem in 90% of cases. Only in 230 cases did the anticipated doses exceed 5 rem. The concentration of the main dose-forming nuclides, caesium-137 and caesium-134, in milk products, potatoes, vegetables and fruit produced in the contaminated region outside the 30-km zone was 0.5x10-8 Ci/kg. (author).

Authors

Buldakov, L.A.; Avetisov, G.M.; Balonov, M.I.; Konstantinov, Yu.O.

Descriptors

cesium 134; cesium 137; chernobylsk-4 reactor; contamination; dose limits; radiation accidents; radiation doses; radiation monitoring; radiation protection; accidents; beta decay radioisotopes; beta-minus decay radioisotopes; cesium isotopes; electron capture radioisotopes; enriched uranium reactors; graphite moderated reactors; hours living radioisotopes; intermediate mass nuclei; internal conversion radioisoto; isomeric transition isotopes; isotopes; lwgr type reactors; monitoring; nuclei; odd-even nuclei; odd-odd nuclei; power reactors; radioisotopes; reactors; safety standards; thermal reactors; water cooled reactors

Subject Category

Actual Accidents

Source

Report; International Atomic Energy Agency, Vienna (Austria); Medical aspects of the Chernobyl accident; IAEA-TECDOC--516.; Jul 1988.; 381 p.; p. 81-89.

Place of Publication

International Atomic Energy Agency (IAEA)

Availability

Available from INIS in electronic form.