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Open Path Detection of Hazardous Gases

Open Path Detection of Hazardous Gases. Technology Overview. Open path, non-contact chemical detection Multiple chemicals detected and identified by a single detector Rapid detection and identification (<1 sec) Sensitive, specific, reliable and robust

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Open Path Detection of Hazardous Gases

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  1. Open PathDetection of Hazardous Gases

  2. Technology Overview • Open path, non-contact chemical detection • Multiple chemicals detected and identified by a single detector • Rapid detection and identification (<1 sec) • Sensitive, specific, reliable and robust • Low maintenance and low cost of ownership Avir Sensors Proprietary

  3. ChemSight™ Architecture Based on infrared spectrometry operating in the 830-1250 cm-1(fingerprint region) 2000-3300 cm-1 spectral ranges Avir Sensors Proprietary

  4. IR Spectrum Parsing IR spectrum absorption curve is parsed into 16 segments Each of the 16 segments is “zeroed out” to create a “background” Chemicals passing through the line of sight absorb known frequencies of IR. The ChemSight accurately detects and identifies the signature across a wide range of concentrations. Avir Sensors Proprietary

  5. Avir Sensors Proprietary

  6. Open Path, Non-contact Chemical Detection • Large coverage area • No contact required for detection and identification and, consequently, no sensor poisoning • Stand off detector does not require predicting potential release areas • Applicable to inaccessible locations • Designated a Department of Homeland Security SAFETY Act Qualified Anti-terrorism Technology (QATT) Avir Sensors Proprietary

  7. Instant Alert and Identification • Patented ChemVECTOR™ algorithm recognizes and identifies chemical’s infrared signatures in one second • Detection and identification confirmed over user-defined intervals (30 seconds typical) • Large on-board database of chemical signatures • User configurable alert and alarm actions • Easily operated by untrained personnel Avir Sensors Proprietary

  8. Selected Hazardous Gases Avir Sensors Proprietary

  9. Sensitive, Specific, Reliable, and Robust • Patented ChemVECTOR™ detection and identification algorithm allows: • Chemical detection and identification well below IDLH • Detection of high and low chemical concentrations • Rejection of background interferants while maintaining trace level sensitivity • Full system verification using on-board confidence tester • Sealed to IP66 standards for continuous operation in harsh environments • Less than 20 watts power consumption Avir Sensors Proprietary

  10. Path Integrated Concentrations Avir Sensors Proprietary

  11. Representative Sensitivities(Over 100 meter path) All units in ppm 1 Second 30 Seconds Avir Sensors Proprietary

  12. Receiver Operating Characteristic(ROC) Curves • ROC curves describe the likelihood of correct dichotomous decisions • a patient has a disease / does not have a disease • an anomaly has been detected / has not been detected • a chemical is present / not present true positive rate: TP/(TP+FN) {probability of identification} false-positive rate: FP/(TN+FP) {probability of false-identification} Avir Sensors Proprietary

  13. Illustrative ROC Curves 1.0 CT brain lesions Mammography screening Diabetes screening Polygraph (police) 0.5 True Positive rate CT brain lesions: AUC 97% mammography: AUC 78-91% diabetes: AUC 81% polygraph: AUC 55-75% 0 False Positive rate 0.5 1.0 Avir Sensors Proprietary

  14. ChemSight™ ROC Curves 75 ppm·m ammonia, 1 sec average Avir Sensors Proprietary

  15. ChemSight™ ROC Curves 75 ppm·m ammonia, 30 sec average Avir Sensors Proprietary

  16. Low Maintenance, Low Ownership Cost • No consumables • No ongoing calibration required • Detector is monitored for blockage, dirt accumulation and other fault diagnosis • Interfaces with standard security software systems • New chemical signatures added to database via software • On-board, full system confidence tester activated at user defined intervals Avir Sensors Proprietary

  17. Typical Applications • Perimeter protection • HVAC systems • Railway platforms • Ports • Airports • Stadiums • Chemical manufacturing and storage facilities • Manufacturing facilities • Environmental monitoring • Schools Avir Sensors Proprietary

  18. Return on Investment Avir Sensors Proprietary

  19. Technology Heritage • Designated a Department of Homeland Security SAFETY Act Qualified Anti-terrorism Technology (QATT) • Metro Rail • Industrial Installations • Carbonated beverage manufacturing • Defense Logistics Agency • Institutional Ventilation Avir Sensors Proprietary

  20. Mahalanobis Distance Technique Avir Sensors Proprietary

  21. Mahalanobis Distance • The Mahalanobis Distance is a mathematical tool that is part of ChemVECTOR™, a patented detection and identification algorithm unique to the ChemSight™. • When a hazardous gas or interferant crosses the IR beam, ChemVECTOR™ determines: • the mathematical magnitude relative to ambient air for detection • the mathematical proximity to signatures in the chemical database for identification Prasanta Chandra Mahalanobis Avir Sensors Proprietary

  22. Mahalanobis Distance Plot Ammonia at 70°F/30% RH, 30 sec averaging Avir Sensors Proprietary

  23. Uniqueness of ChemVECTOR™ • The MD-based mathematics in ChemVECTOR™ allow reliable detection and identification when over a wide range of concentrations even in the presence of a heavy load of interferants. • Unlike alternative algorithms (e.g., principal component analysis - PCA), ChemVECTOR™ allows chemical signatures to be added to the signature database in any combination without recalculating the entire database. • Detection and identification thresholds can be adjusted by ChemVECTOR™. Avir Sensors Proprietary

  24. Physical and Software Schematics Avir Sensors Proprietary

  25. ChemSight™ Detection and Identification Detection Identification Identification occurs when a new signal matches a signature in the library. For positive identification, the match needs to be within a mathematically determined threshold by ChemVECTOR™. When positive detection occurs but the signal is outside the identification threshold the ChemVECTOR™ issues an “Unknown” message. • Detection occurs when a new signal significantly exceeds background noise level. • A mathematical threshold is set to create an acceptable level of false alarms. This threshold defines sensitivity. Avir Sensors Proprietary

  26. ChemSight™ Optical Layout 3) Band pass filters parse spectrum and send signals for processing 1) IR Light Enters Detector 2) Rotating Mirror concentrates light on detector array Internal Layout of ChemSight™ Avir Sensors Proprietary

  27. ChemSight™ Detector Dimensions 7.0” 7.5” 22.5” Avir Sensors Proprietary

  28. ChemSight™ Source Dimensions 14” 14” 8” Avir Sensors Proprietary

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