UNARM (UNattended And Remote Monitoring) overview

Unattended monitoring systems developed at Los Alamos National Laboratory have been installed in facilities for International Atomic Energy Agency (IAEA) use for the last 20 years. These systems allow for more efficient use of inspection resources and more rigorous coverage of IAEA facilities. As of today, the primary sensor types are radiation, video, and binary switches such as seals, but provision to accommodate additional sensor types is an important concept in UNARM. Interfaces to vendor hardware are defined, and being developed as needed. A component of the UNARM approach is the association of time stamps with every piece of data. Additionally, any sensor can trigger any other sensors to record data. For example, radiation signals can be used to trigger camera systems, thereby providing a reliable way to screen out superfluous images. Alternatively, a door switch can trigger the sensors inside a room, indicating whether the activities inside involve nuclear material. A second generation of unattended and remote monitoring (UNARM) systems has been developed at Los Alamos National Laboratory for use in nuclear fuel cycle facilities. Systems have been installed for International Atomic Energy Agency (IAEA) use and evaluation in Japan and Kazakhstan. Excerpts of experience in these locations are presented. An important sensor type is radiation, which senses an attribute unique to the radioactive material being safeguarded. Several radiation sensor types have been installed successfully to date, they vary from sub-one percent nondestructive assay instruments to go/no-go threshold detectors. The reliability of the radiation sensors is typically less than one failure per sensor per year, sometimes less than 1 failure per sensor per 100 years. UNARM systems allow for more efficient use of inspection resources and more rigorous coverage of IAEA facilities. Inspector visits have been reduced substantially for sites in Japan and Kazakhstan. UNARM systems are either remote-ready or transmitting data summaries off-site (if the facility has agreed). Data compaction occurs before transmission to minimize transmission costs. However, all of the data is archived on-site if the inspection authority needs it. The system is robust. If a sensor goes down, the state-of-health component in UNARM records when and which sensor went down. If off-site transmission is operational, state-of-health status can be transmitted off-site daily. Consequently the inspection authority can be informed of the need for repair before they start traveling to the site. They can bring spare parts and the necessary personnel to address the repair need promptly. UNARM systems include a suite of flexible data review tools. These tools are being refined as IAEA needs and experiences dictate. The automated analysis and review points the inspectors to the activities which need further evaluation, while allowing the inspector to focuses his or her attention on any data. One sensor type detects radiation, an attribute unique to the material being safeguarded. This capability allows an inspector to easily distinguish between activities involving nuclear material (which are of interest) from a wide variety of activities not involving nuclear material (which are not of interest). Sensor positions are selected and thresholds adjusted to optimize the sensitivity to events of interest. The chance of missing an event of interest is reduced significantly. The data evaluation tool can be configured with various thresholds, and it reviews all of the data. Thus the inspector can perform several reviews of the data acquired during the inspection period with different criteria. The inspector can schedule his or her activities more effectively with this processing of the data