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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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INL makes a case for eliminating ALARA and setting higher dose limits
A report just released by Idaho National Laboratory reviews decades of radiation protection standards and research on the health effects of low-dose radiation and recommends that the current U.S. annual occupational dose limit of 5,000 mrem be maintained without applying ALARA—the “as low as reasonably achievable” regulatory concept first introduced in 1971—below that threshold.
Noting that epidemiological studies “have consistently failed to demonstrate statistically significant health effects at doses below 10,000 mrem delivered at low dose rates,” the report also recommends “future consideration of increasing this limit to 10,000 mrem/year with appropriate cumulative-dose constraints.”
Kosuke Aizawa, Kaoru Fujita, Hideki Kamide, Naoto Kasahara
Nuclear Technology | Volume 189 | Number 2 | February 2015 | Pages 111-121
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-156
Articles are hosted by Taylor and Francis Online.
The Japan Sodium-cooled Fast Reactor (JSFR) is studied as an advanced loop-type sodium-cooled reactor. A selector-valve (SV) mechanism is adopted in the design of JSFR for its failed fuel detection and location (FFDL) system. JSFR has only two FFDL units for 562 core fuel subassemblies to reduce construction cost by decreasing the reactor vessel diameter. Consequently, one SV-FFDL unit must handle about 300 subassemblies. Because of the large number of subassemblies per unit, it is predicted that the total duration for measuring all the fuel subassemblies becomes long. In addition, JSFR adopts an upper internal structure (UIS) with a slit above the core. In order to detect the fission products from the subassemblies below the slit, additional sampling nozzles for the FFDL are set in the UIS around the slit. In previous water experiments and numerical simulation, the sampling performance for the subassemblies under the UIS slit has been evaluated to be lower than those under the normal UIS position. In this paper, the outline of the FFDL system is shown, which can be applied to a large number of fuel subassemblies in a compact reactor vessel. The detection capability of the FFDL system was studied to achieve the design conditions. Operation modes and procedures of the FFDL system were also investigated.
