Modeling 137Cs Atmospheric Dispersion and Assessing Associated Risks in a Hypothetical KLT-40S Reactor Accident

Neamati, Komeil; Shayesteh, Mohsen; Beshkam, Ali; Karimi, Javad

doi:10.22034/IJRRS.2025.8.1.7

Modeling 137Cs Atmospheric Dispersion and Assessing Associated Risks in a Hypothetical KLT-40S Reactor Accident

Document Type : Original Research Article

Authors

Komeil Neamati

Mohsen Shayesteh

Ali Beshkam

Javad Karimi

Center for Science and Technology of Physics, Faculty of Basic Sciences, Imam Hossein Comprehensive University, Tehran, Iran

10.22034/IJRRS.2025.8.1.7

Abstract

Nuclear emergency management prioritizes minimizing radioactive releases to protect public health and environmental systems. Radiological incidents can cause widespread ecosystem contamination with multi-generational consequences. This study employs predictive modeling to assess risks across all incident phases using computational tools and analytical methods.
This study evaluates a hypothetical accident scenario involving a one-hour atmospheric release of ¹³⁷Cs from a Russian KLT-40S small modular reactor (SMR) during peak operation in the Chabahar region. Utilizing the RASCAL computational code, a regulatory-endorsed tool for radiological emergency response, the research analyzes the isotope's dispersion dynamics over nine hours.
This paper provides both a methodology for identifying hazard zones and a decision-support resource for emergency management officials during incident response. Implementation of fundamental protective actions, based on established protocols and real-time incident conditions, remains the responsibility of local authorities according to quantified risk levels.

Keywords

Cesium-137

KLT-40S

Nuclear Accident

Radiological Dispersion

RASCAL code

Subjects

Case Studies Related to Reliability, Risk and Safety

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