Authors: Dieter Guelle, Andy Smith, Adam Lewis, Thomas Bloodworth EUROPEAN COMMISSION A book about metal detectors, covering detection procedures in the field, and the testing and evaluation of metal detectors for humanitarian demining Metal detector handbook for humanitarian demining A book about metal detectors, covering detection procedures in the field, and the testing and evaluation of metal detectors for humanitarian demining Authors Dieter Guelle, Andy Smith, Adam Lewis, Thomas Bloodworth Acknowledgements We acknowledge help, advice and invaluable input from the following individuals. While they share in any merit this book may deserve, any errors and failings remain the authors’ alone. For advice and assistance with technical aspects, special thanks to Yogadhish Das. For help and advice on a wide variety of other aspects, our thanks to Jacky D’Almeda, Roger Hess, Tim Lardner, Russell Gasser, Ken O’ Connell, Franciska Borry, Marta Garotta, Gian Luigi Ruzzante, J. T. (Theo) van Dyk, Edgardo Maffia, Pete Hindy, and Chris Leach. Many other people have helped in small ways — too many to mention by name. Our thanks to you all. © All photographs and diagrams are copyright of the authors unless otherwise acknowledged. Europe Direct is a service to help you find answers to your questions about the European Union New freephone number: 00 800 6 7 8 9 10 11 A great deal of additional information on the European Union is available on the Internet. It can be accessed through the Europa server (http://europa.eu.int). Cataloguing data can be found at the end of this publication. Luxembourg: Office for Official Publications of the European Communities, 2003 ISBN 92-894-6236-1 © European Communities, 2003 Reproduction is authorised provided the source is acknowledged. All photographs and diagrams are copyright of the authors unless otherwise achnowledged. Printed in Italy Foreword Working in a research environment, it is always of con- books available, which present the actual state of knowl- cern when I am confronted with statements, like ‘To date, edge and which are written by experts in both mine clear- technology has had only a marginal impact on mine ance and technical development in easily understandable action equipment.’ Therefore, it was a very rewarding language. The handbook in front of you is such an moment when, earlier this year, I was able to communi- example combining these vital ingredients. cate the results of the European Committee for Standard- isation (CEN) working group on an agreement by an An interesting point that arises from the handbook is that international community of experts on how to test and deminers working in the field can provide useful informa- evaluate metal detectors to be used in humanitarian mine tion to researchers and developers by making simple clearance. measurements to record the conditions that they meet, for example, by measuring the soil properties. During the work on the establishment of this workshop agreement, it became obvious that there are at least two I am pleased that the Joint Research Centre (JRC) has been areas related to metal detectors that need further able to contribute to the production of this handbook research. The first one is the electromagnetic characterisa- and I hope that it will soon become a reference for those tion of soils and terrain in general terms, in order to pre- who are confronted with the challenging task of mine dict the performance of metal detectors in different clearance. mined areas. The second one is the assessment of the per- Dr Alois J. Sieber formance of mine detection on the basis of reliable statis- Head of Unit,‘Humanitarian Security’ tical testing. Work in both demanding areas of research is Institute for the Protection and Security now in progress. of the Citizen (IPSC) Joint Research Centre, European Commission, In order to ensure that our research efforts will make an Ispra (VA), Italy impact in humanitarian mine clearance, it is vital that the results can be implemented by those working in the field. To achieve this, it is important to communicate the results achieved, through training sessions and presentations in a digestible way. It is therefore important to have hand- 3 Introduction Dear readers, This handbook instructs the reader on how to confidently assess their detector’s ability in the place where they must I have been using metal detectors of one kind or another work. The problem of electro-magnetic ground is ad- for over 20 years. First with the US Army, and for the last dressed in detail, including advice on how to predict the five years while establishing and managing humanitarian clearance-depth that will be possible in other areas. The clearance programmes in the Balkans, Asia and Africa. book also includes detailed advice on how to conduct com- Part of my role has been to train local deminers in how to parative trials of metal detectors. use a range of different detectors in both shallow and deep-level searches. None of this is theoretical. It is all based on genuine hands-on experience and the solutions are practical to use in the field. Over the last 10 years, detector designs have changed and The book includes a quick field-user index and is even printed the features available have become more sophisticated. on tough, washable paper so that it will survive field-use. With this, I have had to learn constantly about the strengths and weaknesses of the new equipment. Manu- For those who want to understand how detectors work in facturers have usually done their best to assist, but they more detail, there is a technical chapter. Even this is writ- rarely understand exactly what we need in the field or the ten in simple language so that most people will be able to understand it. conditions we will be using it in. So I have usually had to find my own ways of getting the answers I was looking for. I recommend all trainers to read this book and all site managers to carry a copy into the field. If the rules out- Over the past 10 years, accidents have occurred because lined in this book are followed and adapted when neces- deminers and their supervisors have not understood the sary, deminers/operators will be safer and we will all be limitations of the detector they were using. It is essential able to have greater confidence in the depth and for the user to know the real detection depth that can be thoroughness of clearance that has been achieved. achieved at the task site and what is a safe rate of for- ward advance. Both of these depend on what the de- Cheers, miner is searching for, but fortunately the smallest target Roger Hess that may be present in a particular area can usually be Demining and Explosive Ordnance Disposal Technical predicted. Consultant 5 Abbreviations and acronyms Throughout this book, the following abbreviations and EMI electromagnetic interference acronyms are used. EOD explosive ordnance disposal ADP Accelerated Demining Programme ERW explosive remnants of war AG anti-group (mine) FFE free from explosive AP anti-personnel (mine) FNA fast neutron analysis AT anti-tank (anti-vehicle) (mine) GC ground compensating (of metal detectors) CCW United Nations Convention on Conventional GICHD Geneva International Centre for Humanitarian Weapons Demining CEN European Committee for Standardisation GPR ground-penetrating radar CWA European Committee for Standardisation GPS Global Positioning System workshop agreement GRH ground reference height DDAS Database of Demining Accidents HD humanitarian demining DNT dinitroluene HE high explosive EDD explosive detecting dog ICBL International Campaign to Ban Landmines EDR explosive detecting rat IMAS International Mine Action Standards EIT electrical impedance tomography IPPTC International Pilot Project for Technical EM electromagnetic Cooperation 7 IR infrared UXO unexploded ordnance ITEP International Test and Evaluation Programme WWI World War One ITOP International Test Operational Procedures WWII World War Two standards NATO North Atlantic Treaty Organisation NGO non-governmental organisation NQR nuclear quadrupole resonance PE plastic explosive QA quality assurance RDX Research Department Explosive (cyclonite) SD self-destruct SDA self-deactivate TNA thermal neutron analysis TNT trinitrotoluene (explosive) UN United Nations UNADP United Nations Accelerated Demining Programme UNMAS United Nations Mine Action Service 8 Definitions To prevent constant repetition, the authors have adopted detected. The greater the distance between the search- some simple definitions that the reader should under- head and the target at which a detector signals, the stand before reading the book. Each follows what we greater its ‘sensitivity’. believe is the ‘normal’ field-use of terminology. Magnetic ground: The expression ‘magnetic ground’ is Contaminated ground: The expression ‘contaminated used throughout this book to indicate ground that has ground’ is used to refer to ground with pieces of manu- electro-magnetic properties that make a metal detector factured metallic material in it. The metallic material may signal. The cause may be spread throughout the ground be fragments from explosive devices, bullets, casings or over a wide area, or may be erratic such as when some discarded material with a metallic content. rocks, stones or building blocks make the detector signal. Detector sensitivity: The expression ‘detector sensitiv- Search-heads or coils: Metal detector search-heads are ity’ is used to refer to the metal detector’s ability to locate sometimes called the ‘coil’ or ‘coils’. Throughout this book a target at varying depths, so is directly related to the dis- the terms are used to refer to the same part of the metal tance from the search-head at which a target can be detector. 9 Contents Chapter 1: Background to humanitarian 15 2.3.3. Batteries 34 demining 2.3.4. Locating metal/mines 35 1.1. The development of mines 18 2.4.