A peer-reviewed journal published by K. N. Toosi University of Technology

‎Real-‎t‎ime radioisotope identification and localization‎: ‎A scalable and low-cost solution for environmental monitoring‎

Document Type : Research Article

Authors

Radiation Applications Research School‎, ‎Nuclear Science and Technology Research Institute‎, ‎Tehran‎, ‎Iran

Abstract
To counter the growing threat of illicit radioactive material trafficking, we developed the Radioactive Detection System (RDS), a scalable, low-cost sensor network for real-time radioisotope identification and localization. Each node combines inexpensive detectors (NaI(Tl) scintillation spectrometers or plastic scintillators) with existing surveillance cameras. Machine-vision algorithms fuse radiation measurements with visual tracking to simultaneously quantify intensity and precisely locate moving sources in complex and dynamic urban settings. Laboratory and field tests using concealed sources carried at pedestrian speeds (0.5-1.2 m.s-1) showed: (i) detection and visual localization of a 100 µCi Cs-137 source in 8-25 s; (ii) reliable spectroscopic identification of the Cs-137 within approximately 100 seconds under the reported laboratory testbed configuration. The multi-modal design substantially enhances sensitivity, specificity, and robustness against background fluctuations. With low per-node cost and straightforward integration into existing infrastructure, RDS enables practical large-scale deployment for continuous monitoring of public spaces, critical infrastructure, border checkpoints, and high-security areas, providing an effective tool for radiological threat mitigation.

Highlights

  • Real-time urban tracking of radioactive sources with visual-radiation fusion.
  • Low-cost, scalable sensor network using cameras and scintillation detectors.
  • Reliable spectroscopic ID of Cs-137 and Co-60 at walking speeds.
  • Multi-modal fusion boosts detection accuracy and background resilience.
  • Enables practical city-scale radiological monitoring with minimal setup.

Keywords


Copyright
RPE is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0).

Conflict of Interest
The authors declare no potential conflict of interest regarding the publication of this work‎.

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Volume 7, Issue 2
Spring 2026
Pages 57-66

  • Receive Date 20 October 2025
  • Revise Date 03 May 2026
  • Accept Date 06 May 2026