Utvikling og bruk av hund for søk etter eksplosiver – sluttrapport

The Norwegian Public Roads Administration (NPRA) and the Norwegian Defence Research Establishment (FFI) have cooperated in a pilot project, developing an application where dogs detect explosive remnants. The dogs are used as a health and safety measure to reduce the risk for construction workers to encounter dynamite remnants from earlier enterprises. The measure has become a success, and the need for the application is increasing. The project demonstrates how extremely well dogs can detect scents. Dynamite remnants can hardly be detected by other methods. A dog can be trained to detect all kinds of substances, it is effective and flexible, and it will soon confirm whether the actual substance is present at the location. This report gives an overview of the activities in the project and presents all the search operations that have been conducted. Results from the characterization of samples of dynamite remnants taken during search operations are presented. The search application has been developed through more than 700 days of searching in tunnels and along roads, in avalanche areas, at closed down shooting ranges and at different sites where explosive remnants are likely to be present from earlier use of explosives. Dogs and dog handlers from the Military dog training school have participated in the project. After the military training and certification, the dogs have been further developed during the project. They are now especially fit for all kinds of search categories to be used at most construction works. The dogs will not be available after the end of the project, and there is a need for civilian companies to take over. The project has contributed to the development of a civilian application that can deliver comparable search capacities. The council “Bransjerådet for fjellsprengning” has been provided with a basis to set up requirements for a civilian certification of these kinds of dogs and dog handlers. Dynamite samples found during search operations have been characterized in order to investigate what the dogs smell when they detect the dynamite remnants. Chemical analysis shows that the composition of the samples varies a lot. The samples contain various concentrations of one or several of the explosives ammonium nitrate (AN), ethylene glycol dinitrate (EGDN), nitroglycerine (NG), trinitro toluene (TNT) or dinitro toluenes (DNTs) in addition to unidentified components. Sensitivity measurements show that many of the remnants still are quite sensitive. This is probably governed by the amount of explosives in the samples and not necessarily which type of explosives. Identification of other components in the samples and analysis of the vapor phase above the remnants may give more information about what the dogs smell when they detect the remnants. Dynamite remnants and duds that are well hidden under the road cover without being exposed to air and water may still be in good shape and thus pose a risk. In order to detect these remnants it is necessary to remove the road cover and the masses layer by layer with dogs searching every new surface as it is revealed. The remnants will most often be located in the lower part of the masses. Remnants located in open drill holes will more easily be exposed to air and water, which can degrade the dynamite composition. Humid conditions, water on surfaces and cold weather may influence the odors and the detection of the remnants.