ASPECT Sensor Suite Information:
The US EPA National Decontamination Team's Airborne Spectral Photometric Environmental Collection Technology (ASPECT) Program has been providing emergency response chemical identification and mapping support to the chemical/hazardous materials sector since 2001. The ASPECT Program is a National Chemical/Radiological emergency response mapping capability. Its primary mission is to provide chemical specific information to the first responder in a form that is accurate, timely, useful and compatible with existing information dissemination infrastructures.
ASPECT is a multi-spectral/hyperspectral emergency response airborne sensor suite operated by the US Environmental Protection Agency. Its primary role is to provide the First Responder with timely standoff detection and quantification data on the nature and extent of gaseous chemical releases. Additionally, ASPECT is sometimes deployed to provide chemical and radiological detection and identification capabilities for specific NSSE and SEAR 1&2 level events.
The success of the ASPECT Program is due to the cooperative efforts of the following agencies and organizations:
US EPA National Decontamination Team
National Geospatial Intelligence Agency Basic and Applied Research Office
The ASPECT airborne platform consists of a complementary remote sensing sensor suite including a wide area multi-spectral infrared line scanner, a hyperspectral rapid scan NADIR configured Fourier Transform infrared spectrometer, as well as a gamma ray spectrometer. This suite is mounted in a medium sized twin-engine aircraft equipped with belly portals. Specific details of this platform have been presented in technical journals and conference proceedings. In general, the package generates a wide angle (60 degrees) chemical specific image with companion chemical identification information. The resulting radiometric image is calibrated and constructed in a format permitting immediate use by the first responder or inclusion into most GIS systems. All data collected is processed to compensate for airframe attitude and to include geo-location content. At a standard altitude (670 meters) and airspeed (56 meters/second), the line scanner system will image a swath about 770 meters wide or about 2.5 Km2 per minute. An infrared pixel resolution on the order of 0.5 meters is typically obtained. This coverage permits most incidents to be imaged using a single 15-second data collection pass over the scene.
The ASPECT sensor suite is mounted in a twin engine aircraft and uses the principles of remote passive infrared detection to image, map, identify, and quantify chemical vapors and plumes, as well as other remotely sensed observable phenomenology relevant to mitigation of emergency response situations on the ground. A wide-area (one half mile wide) infrared imager coupled with a high speed Fourier Transform spectrometer permits plume measurements to be made at a rate of about two square miles per minute.
Supporting data including high resolution aerial digital photography and digital video are concurrently collected along with chemical data. All data is Geo-registered using commercially available INS/GPS coupling technology facilitating map referenced airborne emergency response products. Efficient mission execution requires that data is processed on-board the aircraft for transmission or hand-off directly to the emergency first responder. In addition to chemical detection, radiological data can be collected using a high resolution gamma-ray spectrometer. With these sensors, ASPECT provides an indication of the chemical composition within 3 minutes and confirmation within 40 minutes typically.