The fundamental purpose of the ENCOUNTER project is to increase the safety for Explosive Ordnance Disposal (EOD) personnel and the public through new techniques and methods for dealing with an Improvised Explosive Device (IED).
Based on a set of generalised, but realistic, scenarios ENCOUNTER considered the neutralisation of IEDs using for example laser technologies, clearing charges, improved barrel disruptors or high power microwave technology.
In case of a detonation, mitigation techniques have been developed. Models describing the effects of the different technologies were developed and integrated into a risk analysis tool. The mitigation and neutralisation techniques were evaluated experimentally and rated in terms of reliability and safety for an application in a civilian environment. In addition, software tools and documented methodologies has been developed to assist the EOD personnel and to analyse the risk for a specific scenario. Ethical, financial and societal issues has also been analysed.
A study of the recent attacks in Europe and significant incidents in other part of the world, constituted a number of characteristic threat scenarios against which the technical solutions proposed in ENCOUNTER were tested.
The mitigation methods aim to reduce the impact of an IED by either containing the blast, and/or the fragments. Three mitigation devices have been developed: Blast Containment Tank (BCT), Blast Shield Wall (BSW) and Man-Portable Mitigation Device (MITIED).
Both the BSW and the BCT were proven to be effective and efficient means for blocking high energy fragments and reducing the overpressure of a blast wave. For MITIED simulations suggest and tests have confirmed what simulations suggested, that the device could be very beneficial in reducing peak overpressure in many of the scenarios simulated.
Mitigation techniques: a) Illustration of MITIED. b) BCT, and c) BSW
The neutralisation techniques aim to disable an IED either by slowly burning the charge, disrupting the charge or by destroying the IED triggering mechanism. Four neutralisation techniques were developed and tested: High power laser, clearing charge, high power microwaves and barrel disruptor. The results show that the developed neutralisation techniques were successfully applied in the majority of the investigated scenarios. One of the advantages of the new neutralisation techniques are the improved stand-off capabilities.
Neutralisation techniques: a) Working principle of laser, b) Schematic drawing of clearing charge, c) Laboratory High Power Microwave equipment, d) Schematic of barrel disruptor.
A quantitative risk analysis (QRA) tool has been developed, a desktop application called ENCOUNTER-QRA-Tool, which supports users in quantifying and analysing explosion effects of IEDs in individual threat scenarios.
Graphical user interface of the ENCOUNTER-QRA-Tool
An investigation regarding the ethical issues of the application of IED neutralisation showed that most of the ENCOUNTER technologies are predominantly unproblematic from an ethical point of view.EOD professionals have been questioned about their expectations on the respective technologies and the majority regarded the ENCOUNTER technologies as potentially helpful for their active EOD duty.
Each of the technologies developed in ENCOUNTER will have a cost, but also a benefit relative to current equipment and procedures. The results of the cost-benefit analysis are based on the likelihood of events occurring across the whole of the European Union, the cost of life values also use an average value for the whole of Europe.
FOI, Swedish Defence Research Agency
Dr. Pernilla Magnusson