| 摘要 |
The preferred embodiment uses a chamber which is sized no larger than necessary to hold the particular type, size and shape of the baggage or cargo or containers being examined. This chamber has doors or openings sufficient to allow the easy entry and exit of objects being examined. These doors or openings are easily and quickly moved back and forth, making and breaking a vacuum seal which will withstand internal depressurization to the equivalent of an altitude of 12,000 feet above sea level. For the examination of individuals and items not in the container, a flexible tube is attached to vacuum pump. This flexible tube has a short stiff pipe on the end which is used to probe into areas to collect vapors which are then examined by the detector. The tube from the chamber feeds the air collected in the chamber to the vacuum pump which passes the collected air to the detector. The detector includes gas chromatographs, ion mobility spectroscopy, mass spectrometers or other detectors which have the ability to detect and identify elements, chemicals and compounds at the trace levels as low the nano-pico-femto-gram level or the level on one part-per-billion-trillion-PPB/PPT. The detector provides an alarm if specific pre-set elements, chemical or compounds are identified in the air collected in the chamber or in the flexible tube.
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