AUTOMATED DECOMPRESSION SAMPLING SYSTEM FOR DETECTION OF EXPLOSIVES CONCEALED IN LUGGAGE (FROM NEW CONCEPTS SYMPOSIUM AND WORKSHOP ON DETECTION AND IDENTIFICATION OF EXPLOSIVES - PROCEEDINGS, 1978 - SEE NCJ-58392)

• NCJ Number: 58394
• Author(s): J R HOBBS
• Date Published: 1978
• Length: 4 pages
• Publication Format: Document
• Language: English
• Country: United States of America

Annotation

AN EVALUATION IS PRESENTED OF A DECOMPRESSION SAMPLING SYSTEM THAT AUTOMATICALLY SAMPLES EXPLOSIVE VAPORS FROM LUGGAGE.

Abstract

ALTHOUGH EXPLOSIVE VAPORS FROM DYNAMITE CAN BE DETECTED AT THE SEAMS OF SUITCASES BY USING PORTABLE DETECTORS, THE FACT THAT SUCH SEARCHES TAKE UP TO 2 MINUTES PER BAG MAKES THIS PROCEDURE UNACCEPTABLE IN AIRPORTS. A STUDY ANALYSIS SHOWED THAT A DECOMPRESSION TECHNIQUE WAS A FEASIBLE METHOD TO USE TO DETECT EXPLOSIVE VAPORS AND A CONTRACT WAS AWARDED TO CONSTRUCT SUCH A SYSTEM. THE SYSTEM HAS A PROCESSING RATE OF APPROXIMATELY 6 BAGS A MINUTE WITH THE POTENTIAL FOR PROCESSING 10 BAGS PER MINUTE WITH ELECTRONIC MODIFICATIONS. ANY EXPLOSIVE VAPOR DETECTOR THAT OPERATES AT ATMOSPHERIC PRESSURE CAN BE LINKED TO THE SAMPLING SYSTEM. PRELIMINARY DATA INDICATE THAT, WITH A RESIDUAL VOLUME OF 15 PERCENT OF THE CHAMBER VOLUME, APPROXIMATELY 40 PERCENT OF THE CONCENTRATION OF SULFUR HEXAFLUORIDE TRACER GAS INSIDE A SUITCASE CAN BE REMOVED FROM THE SUITCASE INTO THE DECOMPRESSION CHAMBER. LIMITED TESTING WITH LUGGAGE CONTAINING 8 STICKS OF 40-PERCENT DYNAMITE HAS BEEN 100-PERCENT SUCCESSFUL. FUTURE EFFORTS WITH THIS SYSTEM WILL INCLUDE FIELD TESTING WITH A VARIETY OF EXPLOSIVES AND INCORPORATION OF A FLEXIBLE MEMBRANE TO REDUCE THE RESIDUAL VOLUME IN THE SYSTEM TO 1-2 PERCENT REGARDLESS OF THE SIZE OF THE LUGGAGE. ILLUSTRATION, CHARTS, A PHOTOGRAPH, AND A REFERENCE ARE PROVIDED. (AUTHOR ABSTRACT MODIFIED--KCP)