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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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A better model? Low levels of radiation and health effects
One of the more pivotal issues in facilitating the use of radiation sources—including nuclear power—in the United States (and most of the Western world) is concern about the health effects of low levels of radiation. The current regulatory assumption is that every additional increment of radiation linearly increases the risk of cancer.
Markku Rajamäki, Frej Wasastjerna
Nuclear Science and Engineering | Volume 101 | Number 1 | January 1989 | Pages 41-47
Technical Paper | doi.org/10.13182/NSE89-A23593
Articles are hosted by Taylor and Francis Online.
The reactivity effects caused by fragmentation of nuclear fuel and by simultaneous cooling of the fragments are described. A series of light water reactor (LWR) cases and three speculative scenarios for the Chernobyl accident are considered. Calculations were carried out with the LWR cell burnup code CASMO-HEX. Fragmentation is described by increasing the number of fuel pieces while decreasing their diameter. Cooling is considered to occur as quasi-stationary. Relative movement of the fragments and the coolant is taken into account by varying the water/fuel ratio. Under certain circumstances, substantial reactivity increases are found to occur in both reactor types. These may have contributed significantly to the severity of the Chernobyl accident.