The AccuSense Chemical Recognition System utilizes innovative techniques for identifying chemicals in a gaseous form via a true Dual Hyphenated Gas Chromatograph (DHGC) column comparative protocol. The dual hyphenation gives AccuSense the ability to identify chemicals in two dimensions, resulting in a very low rate of false positives. This enables AccuSense to attain a level of accuracy exceeding 99% within the confines of known elemental signatures in its database. AccuSense also has the unique capability of simultaneously identifying up to 16 chemicals per sample and displaying their respective concentration levels to the very low parts per million (ppm) range (chemical dependent).

Gas Chromatography involves the separation of mixtures of compounds (solutes) into separate components. This is accomplished by means of stationary components (the stationary phase) and mobile elements (the mobile phase). With Gas Chromatography, a sample is vaporized and injected into gas chromatographic columns (two columns in the case of AccuSense) and separated into its components.

The final separation and identification (elution) is achieved by measuring the flow of an inert gaseous mobile phase. The carrier gas serves as the mobile phase that elutes the components of a mixture from a column containing an immobilized stationary phase. Carrier gases (the mobile phase) typically include helium, argon and nitrogen, which are chemically inert. AccuSense uses internally conditioned ambient air as the carrier gas, and thus does not require a separate tank (or other source) of carrier gas. The stationary phase is a solid that has a large surface area at which gas chromatographic separation occurs because of differences in the positions of absorption equilibria between the gaseous components of a sample and the stationary phases.

The ability to implement an effective miniaturized DHGC chemical detector allows AccuSense to provide a two dimensional analysis of any potential hazard. The dual hyphenation allows a comparative analysis in a polarized and non-polarized state, which creates unprecedented accuracy and reliability in AccuSense, and significantly reduces the likelihood of a false positive chemical recognition. The ability to quickly analyze and compare data from column to column, with accurate and timely results, is a major technology breakthrough in a portable product.

An inherent problem with other Gas Chromatography implementations is the valve requirements for passing elutive gases into the columns and the capture and storage of these elutive gases. The type of valve mechanisms required for use in typical gas chromatographic column-based applications is cost prohibitive and in most cases non-portable. The implementation of proprietary air flow and filter technology in AccuSense not only significantly reduces cost, but eliminates potential contaminants that can be present in other configurations, thus increasing the system accuracy and life of the product.

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