Assessment of Radiological Dose around a 3-MW TRIGA Mark-II Research Reactor

Abstract

A hypothetical accidental case of a 3-MW TRIGA Mark-II research reactor has been assumed to assess the radiological consequences due to the deposition of 137 Cs and Sr have been found to be within the ranges of 0.005-0.014 µSv hr -1 , 0.013-0.036 µSv hr -1 and 0.018-0.05 µSv hr -1 , respectively for all the directions, which are below the measured background dose limit 0.25 µSv hr -1 and also within the IAEA acceptable dose rate limit of 0.5 µSv hr -1 . The calculated low doses due to the aforementioned radionuclides can be considered negligible with regard to the radiation hazards. The relationship between total effective dose rate for various pathways (i.e. immersion, inhalation, ground deposition, and ingestion of contaminated vegetation, milk, meat) and air concentration in all the directions has been established. Obtained relation reveals that the total effective dose rate is directly proportional to the air concentration, and the overall proportionality constants for 137 Cs and 90 Sr radionuclides have been obtained as 0.57 and 0.28, respectively. This study might provide information on the radiological safety required for the radiation protection purposes of the people living in the vicinity of the reactor site.

Comparative Radiation Dose Study of a Hypothetical Accident in a Research Reactor

“…12 The external exposure is determined by the radiation emitted by the radionuclides and absorbed by the body, and the internal exposure is the result of the incorporation of deposit material into the human body by inhalation or ingestion. 13 The postulated accident scenario is similar to that described by Villa et al 5 The selected possible hazardous radionuclides which define the source term have been exploited as an input for air dispersion modelling and radiation dose calculations using meteorological data of the site. Only noble gases and halogens were considered in this study since they are viewed as volatile nuclides, and will decay and deposit their energy into the ecosystem, thus contributing to radiation risk and threat to human health.…”