Detection of hazardous materials can be a very costly endeavor. However, there are ways to simplify the process, reduce costs, and increase the performance of previously purchased legacy equipment. Leveraging the operating environment and informing personnel to make better decisions are two methods for achieving these goals.
When addressing a detection problem, there are four interconnected, top-level “components” of the system to consider: the candidate technologies, the operating environment, the threat, and the personnel that are operating, sustaining, and making decisions based on the sensor’s performance. Available technology defines the limits of what is possible to accomplish with hardware only for any given system. These limits can be pushed with creative implementation of systems engineering and operational protocols. The environment channelizes and steers the agent plume, which affects the threat’s ability to effectively hit its target. The environment can create signal clutter that degrades different technologies’ abilities toentify threats. Personnel need information about the detected threat that allows them to make knowledgeable decisions in time to make a difference.
All four components must be addressed in system design, but the most important part of the system is the people, and the best way to ensure that part of the system works is to keep the design simple. Using simplicity as a principle of design can improve system performance, user suitability, and life-cycle costs.
Incorporating Sensor Node Networks for System Self-Repair One of the challenges inherent in detecting a biological or chemical threat cloud is that these clouds concentrate in low areas and in eddies behind large structures. In effect, this demonstrates how the threat and the environment become part of the system design. Clearly, the best chance of detecting an attack is to have the sensor nodes in those areas, but placing the nodes there complicates radio connection to the base station. The task of establishing a wireless sensor network, while ensuring best sensor placement can be simplified by incorporating a mesh network radio into each sensor node. The sensors automatically establish a wireless network that is also capable of repairing itself if a sensor fails. All the operator has to do is emplace the sensor and turn on the power. The sensor node does the rest of the work.
Using Better Toxin Assays for Cost-Effective Sample Collection One challenge of biological agententification is achieving the sensitivity and specificity of Polymerase Chain Reaction (PCR) based technology, but without the PCR’s susceptibility to common environmental interferents (like salts and humic acid from soil) that can shut down the PCR chemistry. Using assays that are tolerant of interferents eliminates the need for costly and time-consuming sample cleanup, and accelerates the overall time to go from sample collection toentification result.
In addition, using activity-based toxin assays that work on PCR not only reduces the amount of equipment required toentify the full spectrum of bioterrorism agents, it also provides a critical piece of information for decision makers on the spot – that is, “Is the toxin still a hazard, or has it degraded to a benign state?” The faster decision makers know what the true threats are, the faster they can make accurate decisions on protecting those who have potentially been exposed. These are some examples of how building simplicity into something as seemingly minor as bioidentification chemistries can produce significant enhancements for the users in terms of cost to employ the technology, and ability to make timely, accurate decisions.
Reducing Signal Clutter for Trace Detection The final example of how simplicity in design can create high-performance payoffs involves detection of trace levels of chemical and biological agents. Rather than purchasing a completely new system, existing technologies that already have excellententification capabilities can be optimized by improving the contaminant collection process. Essentially, reduce the signal clutter so the already capable instruments get a clear read of the target. It is much more cost effective to improve the sampling process for trace contaminants – including explosives, drugs, chemical warfare agents, and biological agents – on a wide range of surfaces than to replace costly Raman spectrometer equipment. Among the many advantages of this simple solution to a refractory problem is the ability to rapidly evaluate the presence of trace contaminants in order to improve situational awareness.
According to at least one of the interpretations of Occam’s Razor, “If you have two equally likely solutions to a problem, choose the simplest.”
Timothy Moshier is president of Acumen Detection LLC (www.acumendetection.com), a wholly owned subsidiary of the not-for-profit, research and development firm, SRC, Inc. Acumen Detection develops and produces low-cost, rapid, point-of-need detection andentification capabilities for security, agriculture, and food markets. Prior to joining Acumen Detection, he served as director, Chem-Bio Defense, SRC, where he participated in the development of environmental surveillance systems for chemical and biological aerosol threats (i.e., Aklus Shield and CADIS [Chemical Aerosol Detection andentification System]). Earlier jobs included Massachusetts Institute of Technology Lincoln Laboratory, SPARTA, and 22 years in the U.S. Army, which included operational and biodefense system acquisition assignments.
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