The National Academies

Transit IDEA J-04/IDEA 42 [Completed (IDEA)]

Detection of Radioactivity in Transit Stations
[ TCRP J-04 (Innovations Deserving Exploratory Analysis--The Transit IDEA Program) ]

  Project Data
Staff Responsibility: Harvey Berlin

This project developed and tested prototype devices and methods to detect and identify radioactive material carried into rail rapid transit systems. A prerequisite for the early response and interdiction of such material is the detection and tracking of its location. It is necessary to have the ability to monitor the ambient radiation environment so that in the event of a radioactive device or dirty bomb, emergency response units will have as much information as possible. This project included development, laboratory proof of concept, and prototype testing of the radiation detection system to address this problem.
The prototype system was tested at a station of the Washington Metropolitan Area Transit Authority (WMATA) Metrorail system. The Connecticut Department of Transportation Research Department also participated in this project by providing review and comments.
This project developed hardware and software technology to implement radiation monitoring in transit stations. The proposed system makes use of existing video cameras already installed in many rail transit stations to detect and identify the nature of both ambient radioactivity levels and nearby radioactive materials, for example, radiological dispersal devices or “dirty bombs.” The radiological materials that terrorists might use in the construction of a dirty bomb emit energetic particles that could be detected by the Radiation Event Detection System: Tracking and Recognition (REDSTAR™) system. To identify and distinguish the dirty bomb signature, multiple detectors would be networked into local and remote computers. The computers would use the subcontractor, LiveWave’s FirstView and VirtualPerimeter software, used by WMATA and other transit systems. The actual detection of radiological sources would be performed by REDSTAR software optimized for detecting the artifacts created by energetic particles hitting the detectors. This powerful, inexpensive combination, REDSTAR™, could, therefore, be rapidly and widely deployed with minimal training requirements.
The contractor on this project has established a cooperative relationship with WMATA staff who participated in this project. The guidance received from this partnership will help guide REDSTAR technology R&D in its transit applications. Transit IDEA Project 54, a new Phase 2 project, will build on the results of this completed project, and will install, test, and evaluate a prototype system using security cameras in rail rapid transit stations.

Project Results

Laboratory tests were conducted to evaluate the sensitivity of the hardware detection technologies. The investigators performed tests using three different radioactive sources. The energetic gamma rays emitted by the sources are very penetrating. The laboratory tests demonstrate that the REDSTAR detection system is sensitive to the smallest radioactive source used. Since a detectable amount of gamma rays can pierce significant amounts of lead shielding, it is very unlikely that pedestrians could carry enough shielding to prevent the detection of a significant source.

The REDSTAR™ detectors and software system collect data in the rail rapid transit stations, process that data, and provide any potential alert information to the security personnel in the operations control center. Existing digital security cameras will be used to minimize system cost.

 Figure 1

The current effort is to automate the detection and measurement procedure. The prototype was tested to verify the laboratory detections and to validate current estimates of sensitivity.

Completed Investigation

The hardware and software development and subsequent integration into a prototype were performed in the contractor’s laboratory. In that setting, the sensitivity of the system was measured. Using that data, the investigators made extrapolations to estimate the probable efficacy once deployed in transit stations. One of the tests was in a rail rapid transit station of the WMATA Metrorail system, in Washington, D.C., for analysis and measurement of background radiation level. Additional testing was performed at Memorial Sloan-Kettering Cancer Center using their calibrated radiation sources.

Product Payoff Potential

The early detection of radiological materials has the potential to save lives by alerting security personnel to the presence of such material. By providing this information to a transit control center and law-enforcement authorities, a dirty bomb could be detected.

Product Transfer

Once initial proof-of-concept demonstration of the technology has been satisfied, refinements to the technology will be made and additional trials and demonstrations made to meet different radioactive threat scenarios. The inexpensive and quickly usable nature of the proposed technology should facilitate early deployment.

NTIS # PB2008-101507.

The final report for this IDEA project can be found at:

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