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BANK OF CEYLON
NUCLEAR FUEL SERVICES
summary of MODEL 97 DETECTION TESTS
This test was conducted on 21 - 24 March 1988 at the FBI
FBI TEST RESULTS
While the competition had mixed results with nitro glycerin, Ammonium Nitrate, DNT and TNT, ITI readily found these. None of the equipment found pure PETN or RDX. Dynamite, which was readily detectable by everyone, was not tested in order not to contaminate the test area.
Both automobile and typical office senarios were also used in performance testing. ITI found many of the hidden explosives, whereby the competition had mixed success. The detection capabilities demonstrated by the Model 97 rated above the competition.
FBI TEST PROCEDURE
1. The search method used will be a "directed" search, i.e. pre-numbered areas (labeled with 3 X 5 cards) will be searched by all instruments thus eliminating the search ability of the operator as a variable.
2. No operator, scorer/observer, or witness will be permitted to touch any search area. For example, if a desk drawer is to be sampled it will already be partially open.
3. The Operator is the only person who can determine a "hit" or "miss".
4. Upon receiving a positive response or "hit" followed by a rapid clearing of the detector a second sampling should be performed. Both responses will be recorded.
5. Due to the nature of the exercise, all instruments will be required to operate on battery power.
6. Upon completion of the testing in each area the test results will be signed and sealed in the provided envelope. They should immediately be delivered to the test coordinator.
If an instrument becomes inoperable due to failure, overload or expendable supply replacement the test coordinator must be notified before corrective action is taken. A maximum of 30 minutes is permitted after which time the instrument will be removed form the test phase
and allowed to clear. The sampling can continue at a late point. The event will be recorded by the scorer/observer.
Repeated failure or overload which appears to seriously threaten the time schedule may result in the instrument being declared inoperable by the referee for the remainder of the test phase.
ITI comments on the FBI Explosives Detector
1. We would point out that the devised test scenarios were of the "response" type as opposed to routine screening operations. WE feel it would have been instructive to engineer a security checkpoint scenario in which the operator would have a chance to obtain vapor from inside the cases/packages. It is common practice in checkpoint applications to set conditions and employ techniques to enhance detection. For example it would have been useful to show the benefits of some of the techniques used to extract vapor from packages. These include non-contact thermal pumping (raising the package temperature rapidly by the use of a high powered light), burping of flexing the package to expel air and penetration of the barrier with needle probes. Also the atmosphere in the vicinity of the test would not be heavily contaminated with both halogens and nitro compounds.
2. The results of sniffing Semtex explosive were not reported because it has been assumed that the explosive sample had been contaminated by EGDN. our tests with the Model 97 showed that the Semtex has a very volatile nitro compound in the headspace vapor which is easy to detect this vapor was shown to be DIFFERENT for EGDN.
3. Internationally based terrorist organizations use ANPO and SEMTEX. Inclusion of these materials would have been more typical of the threat faced by some of the Government Agencies.
4. We would like to take the opportunity to point out the difference between discontinuous sampling devices and continuous sniffing devices. The Model 97 is a continuous sniffing device which will continue to operate in a contaminated background as was demonstrated during the first morning of the trials. The contaminated background, however, may have impaired the effective sensitivity of the instrument.
5. Contaminated backgrounds and hang-up from previous tests causes false positive in batch sampling detection systems. For this reason with this type of instrument, blank samples should be taken after each positive detection until no response is achieved. Unfortunately, no blanks were taken after detecting the pure explosives during the preliminary trials. consequently, the results form the preliminary test on the pure explosives may be misleading.