Concept of Operations or "CONOPS"

An increasing array of instrumentation is available in the battle to prevent the illegal trafficking of nuclear materials. The initial response to prevent radioactive materials smuggling was, naturally, based on the then available instrumentation, radiation portal monitors developed for the steel industry, hand held radiation detectors, laboratory-based high resolution spectrometers. A concept of operations, or “CONOPS” was developed around the use of the existing instrumentation to address the problem as initially perceived. As the application has developed, the implicit problems have become evident in the form of nuisance alarms and the potential for false negatives. In response to these issues, a new generation of in-field instruments have been developed with high resolution spectroscopic capability, potentially changing the CONOPS. Over the same period, experience in actual deployments has demonstrated that the nature and frequency of nuisance alarms varies dramatically from location to location. Airports are not like sea ports; one border crossing is very different to another; mail is not like rail freight. The solutions may differ depending on location, traffic flow, man power, and availability of expertise.

Consequently “one CONOPS does not fit all” and the new instruments allow changes and improvements to be made. The impact of these instruments is explored here.

Independent Expert Estimates of the Innocent alarm rates in various types of traffic flows are given in table 1.

It has been estimated by an experienced expert that it takes 5 to 30 minutes on to resolve an innocent alarm by manual search.

Table 2 contains examples of publicly available data of traffic flows in a number of facilities and situations world-wide. We can use the estimated innocent alarm rates in Table 1 to predict the actual numbers of innocent alarms each day in the facilities listed if PVT (plastic) portal monitors alone were installed.

• Table 1 shows us that on a percentage basis, freight cargo containers have the biggest innocent alarm problem.
• Table 2 shows us that large ports carry immense amounts of freight and therefore will expect high numbers of innocent alarms each day.
• Table 2 also shows us that although alarm rates in people and mail are lower, the huge traffic levels mean that daily alarm rates can be high.

This simple analysis leads us to the conclusion that for a small facility where alarms are not frequent, a Detective Hand-Held Portable Nuclide Identifier used in conjunction with a PVT portal may be the best, most cost-effective CONOPS. A suspect package or container is easily measured with the Detective, and in the event of a query, the spectrum can be emailed to a remote expert, who, because the spectrum is high resolution, will find it easy to identify or analyze further. For the high traffic/high daily alarm rate situation, a manual approach to dealing with innocent alarms is clearly impractical and an automatic system of some kind is called for, most likely in the form of a secondary Advanced Spectroscopic Portal Monitor system (ASP) using high purity germanium (High Purity Germanium).

If we know the daily innocent alarm prediction for a facility, we can calculate the number of ASP portals needed. For example 600 innocent freight alarms per day is an average of one every 144 seconds. For a 40 foot trailer to pass through a portal at 5 MPH will take around 5–10 seconds. So we can conclude that a properly configured ORTEC Detective-ASP could keep up with this innocent alarm rate. So one ORTEC Detective-ASP can deal with the “output” from 50 PVT plastic portals and not cause traffic backlog. (2% alarm rate). This would suggest that even though the ORTEC Detective-ASP may be much more costly than a plastic portal, to use a Detective-ASP to solve the innocent alarm problem in a large facility may add as little as 10–25% to the overall portal monitor costs. Moreover, in smaller facilities where the traffic flows are lighter, an ORTEC Detective-ASP with fewer detector modules (IDMS) may be used and the traffic made to drive more slowly. If the traffic flows increase, the modular system can be easily upgraded to allow higher speed of operation.

At the smallest facilities, hand inspection may still be the most suitable CONOPS. Either way the ORTEC Detective family has it covered.