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Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
×

REDUCING THE THREAT OF
IMPROVISED
EXPLOSIVE
DEVICE ATTACKS
BY RESTRICTING
ACCESS TO EXPLOSIVE
PRECURSOR CHEMICALS

Committee on Reducing the Threat of Improvised Explosive Device
Attacks by Restricting Access to Chemical Explosive Precursors

Board on Chemical Sciences and Technology

Division of Earth and Life Studies

A Consensus Study Report of

images

THE NATIONAL ACADEMIES PRESS
Washington, DC
www.nap.edu

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
×

THE NATIONAL ACADEMIES PRESS 500 Fifth Street, NW Washington, DC 20001

This activity was supported by Contract No. HHSP233201400020B/HHSP23337050 with the U.S. Department of Homeland Security. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.

International Standard Book Number-13: 978-0-309-46407-9
International Standard Book Number-10: 0-309-46407-2
Digital Object Identifier: https://doi.org/10.17226/24862
Library of Congress Control Number: 2018930758

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Printed in the United States of America

Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: https://doi.org/10.17226/24862.

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
×

images

The National Academy of Sciences was established in 1863 by an Act of Congress, signed by President Lincoln, as a private, nongovernmental institution to advise the nation on issues related to science and technology. Members are elected by their peers for outstanding contributions to research. Dr. Marcia McNutt is president.

The National Academy of Engineering was established in 1964 under the charter of the National Academy of Sciences to bring the practices of engineering to advising the nation. Members are elected by their peers for extraordinary contributions to engineering. Dr. C. D. Mote, Jr., is president.

The National Academy of Medicine (formerly the Institute of Medicine) was established in 1970 under the charter of the National Academy of Sciences to advise the nation on medical and health issues. Members are elected by their peers for distinguished contributions to medicine and health. Dr. Victor J. Dzau is president.

The three Academies work together as the National Academies of Sciences, Engineering, and Medicine to provide independent, objective analysis and advice to the nation and conduct other activities to solve complex problems and inform public policy decisions. The National Academies also encourage education and research, recognize outstanding contributions to knowledge, and increase public understanding in matters of science, engineering, and medicine.

Learn more about the National Academies of Sciences, Engineering, and Medicine at www.nationalacademies.org.

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
×

images

Consensus Study Reports published by the National Academies of Sciences, Engineering, and Medicine document the evidence-based consensus on the study’s statement of task by an authoring committee of experts. Reports typically include findings, conclusions, and recommendations based on information gathered by the committee and the committee’s deliberations. Each report has been subjected to a rigorous and independent peer-review process and it represents the position of the National Academies on the statement of task.

Proceedings published by the National Academies of Sciences, Engineering, and Medicine chronicle the presentations and discussions at a workshop, symposium, or other event convened by the National Academies. The statements and opinions contained in proceedings are those of the participants and are not endorsed by other participants, the planning committee, or the National Academies.

For information about other products and activities of the National Academies, please visit www.nationalacademies.org/about/whatwedo.

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
×

COMMITTEE ON REDUCING THE THREAT OF IMPROVISED EXPLOSIVE DEVICE ATTACKS BY RESTRICTING ACCESS TO CHEMICAL EXPLOSIVE PRECURSORS

Members

VICTORIA A. GREENFIELD (Chair), George Mason University

ROBERT G. BEST, Defense Threat Reduction Agency – JIDO

LEO E. BRADLEY, LE Bradley Consulting LLC

JOHN C. BRULIA, Austin Powder Company (Retired)

CARRIE L. CASTILLE, Independent Consultant

DAVID G. DELANEY, University of Maryland

ARTHUR G. FRAAS, Resources for the Future

WILLIAM J. HURLEY, Institute for Defense Analysis

KARMEN N. LAPPO, Sandia National Laboratories

BECKY D. OLINGER, Los Alamos National Laboratory

JIMMIE C. OXLEY, University of Rhode Island

KEVIN F. SMITH, Sustainable Supply Chain Consulting

KIRK YEAGER, Federal Bureau of Investigation

Staff

CAMLY TRAN, Study Director

SAMUEL M. GOODMAN, Postdoctoral Fellow

JARRETT I. NGUYEN, Senior Program Assistant

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
×

BOARD ON CHEMICAL SCIENCES AND TECHNOLOGY

Co-Chairs

DAVID BEM, PPG Industries

DAVID R. WALT, Tufts University

Members

HÉCTOR D. ABRUÑA, Cornell University

JOEL C. BARRISH, Achillion Pharmaceuticals, Inc.

MARK A. BARTEAU, NAE, University of Michigan

JOAN BRENNECKE, NAE, University of Notre Dame

MICHELLE V. BUCHANAN, Oak Ridge National Laboratory

DAVID W. CHRISTIANSON, University of Pennsylvania

JENNIFER SINCLAIR CURTIS, University of California, Davis

RICHARD EISENBERG, NAS, University of Rochester

SAMUEL H. GELLMAN, NAS, University of Wisconsin–Madison

SHARON C. GLOTZER, NAS, University of Michigan

MIRIAM E. JOHN, Sandia National Laboratories (retired)

FRANCES S. LIGLER, NAE, University of North Carolina at Chapel Hill and North Carolina State University

SANDER G. MILLS, Merck Research Laboratories (retired)

JOSEPH B. POWELL, Shell

PETER J. ROSSKY, NAS, Rice University

TIMOTHY SWAGER, NAS, Massachusetts Institute of Technology

National Academies of Sciences, Engineering, and Medicine Staff

TERESA FRYBERGER, Board Director

MARILEE SHELTON-DAVENPORT, Senior Program Officer

CAMLY TRAN, Program Officer

ANNA SBEREGAEVA, Associate Program Officer

SAMUEL M. GOODMAN, Postdoctoral Fellow

JARRETT I. NGUYEN, Senior Program Assistant

SHUBHA BANSKOTA, Financial Associate

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
×

Preface

“Jumping to conclusions is efficient if the conclusions are likely to be correct and the costs of an occasional mistake acceptable. Jumping to conclusions is risky when the situation is unfamiliar, the stakes are high and there is no time to collect more information.”

Daniel Kahneman, Thinking, Fast and Slow

Daniel Kahneman, in Thinking, Fast and Slow, distinguishes between deliberative thinking and intuitive thinking, leaving us to consider the benefits of the former and the pitfalls of the latter in policy making. Deliberative thinking can occur proactively, enabling policy makers to weigh tradeoffs, recognize complexity, and focus on long-term strategies for coping with crises; whereas intuitive thinking, which might occur reactively in the aftermath of a crisis, leans toward rapid and simple decisions based on emotion and familiarity.

Although it has been more than two decades since the United States experienced the truck bombings of the Alfred P. Murrah Federal Building in Oklahoma City and the World Trade Center in New York City, terrorist attacks with smaller-scale improvised explosive devices (IEDs) in Paris, France (2015); Brussels, Belgium (2016); New York and New Jersey (2016); and Manchester, United Kingdom (2017) serve as concrete reminders that IEDs remain a persistent threat to the United States and its allies. One could hardly describe this chain of events as a lull in terrorist activity, but the absence of a recent domestic episode like that in Oklahoma City suggests an opening for U.S. policy makers to deliberatively work through some of the most challenging issues around the threat of IEDs, in a period of relative calm.

Page viii Cite
Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
×

To that end, the U.S. Department of Homeland Security (DHS) asked the National Academies of Sciences, Engineering, and Medicine to consider opportunities to reduce the threat of IED attacks by restricting access to precursor chemicals that can be used to make homemade explosives. In response, the National Academies assembled a 13-member committee of experts on chemistry, energetic materials, supply chain management, economics, defense, law, and other fields to prioritize the precursor chemicals that can be used to make homemade explosives, to analyze the movement of those chemicals through the domestic supply chain and identify potential vulnerabilities, to examine current domestic and international regulation of the chemicals, and to compare economic, security, and other tradeoffs among potential control strategies. The National Academies selected committee members with backgrounds in research, industry, and policy making and with experience on the ground to ensure that we on the committee considered the scientific, practical, and policy aspects of our findings, conclusions, and recommendations.

We spent much of our time establishing priorities, examining the supply chains of those chemicals that we deemed most concerning, and looking for vulnerabilities as the chemicals make their way to end users. In mapping various regulations and voluntary programs to the chemicals’ supply chains to look for gaps, we found more evidence of visibility and oversight, albeit piecemeal, in import, manufacturing, storage, and distribution than in retailing. For that reason, we chose to focus our deliberations on control strategies that could address retail-level vulnerabilities, including those pertaining to e-commerce.

From the outset, we recognized that as long as explosive materials such as black and smokeless powders are readily available, the threat of IED attacks cannot be eliminated; nevertheless, we identified a set of possible control strategies, featuring different types of restrictions on access to precursor chemicals that could play a part in risk reduction. This report considers the benefits, costs, and uncertainties of each approach, but does not provide the comprehensive analysis of specific proposals that would be necessary for policy making.

Drawing inspiration from Kahneman, we argue for treating this report as the starting point of an ongoing deliberative process, which would include a fuller, quantitative analysis of benefits, costs, and uncertainties, not as an end point for decision-making. Even if event-driven policy making is unavoidable, we have tried to lay the groundwork for better policy responses so that in-the-moment decision-making can look more like thoughtful decision-making.

Lastly, I would like to take this opportunity to thank each committee member and the National Academies staff for their contributions and support. It has been an honor to work with such an outstanding group of dedicated individuals.

Victoria A. Greenfield, Chair

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
×

Acknowledgments

The completion of this study would not have been successful without the assistance of many individuals and organizations. The committee would especially like to thank the following individuals and organizations for their contribution during this study:

U.S. Department of Homeland Security, which sponsored the study and provided valuable information on the agency’s responsibilities with the Chemical Facilities Anti-Terrorism Standards (CFATS) program and risk assessment structure. The committee would especially like to thank the director of the Infrastructure and Security Compliance Division, David Wulf, as well as Craig Conklin (Office of Infrastructure Protection) who served as the DHS liaison to the committee and was effective in responding to the committee’s requests for information.

Eva-Maria Engdahl, Ivette Tarrida-Soler, and Michael Berglund of the European Commission and Anne-Marie Fry and Nathan Munson at the United Kingdom’s Home Office for hosting two members of the committee and a staff officer to discuss their current regulations on chemical explosive precursors.

Speakers and invited participants at the committee’s data-gathering meetings. These individuals are listed here: Andy O’Hare, The Fertilizer Institute; Cynthia Hilton, The Institute of Makers of Explosives; Tony Cheesebrough, Tom Colley, Todd Klessman, Kelly Murray, Mike Pickford, and Patrick Starke, U.S. Department of Homeland Security; Matt Hendley and Kevin Sheehan, U.S. Department of Justice – FBI; Col. Bradley B. Preston, U.S. Department of Defense – Joint Improvised-Threat Defeat Organization; Special Agent Will McCray, U.S. Department of Justice – Bureau of Alcohol, Tobacco, Firearms, and Explosives;

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
×

William Hoffman, U.S. Department of Agriculture; James Bevan, Conflict Armament Research; Noel Hsu, Orica; Donald Thomas, CF Industries; Gary Vogen, Yara; Hank Sattlethight, The Aluminum Association; Ross Anderson, Arkema; Chris Gibson, Hawkins Inc.; Julie Heckman, American Pyrotechnic Association; Jennifer Gibson, National Association of Chemical Distributors; David Closs, Michigan State University; Henry Willis, RAND Corporation; Lisa Robinson, Harvard University; Michael Lewis, ANGUS Chemical Company; Kris Griffith, American Pacific Corporation; Daniel Roczniak, American Chemistry Council; Steven Krupinsky, U.S. Customs and Border Protection; Antonio Guzman, U.S. Drug Enforcement Administration; LCDR Adam Cooley and Betty McMenemy, U.S. Coast Guard; Lisa Long and Jeffrey Wanko, U.S. Occupational Safety and Health Administration; Paul Bomgardner and Steven Webb, U.S. Department of Transportation; Philip Davison, Association of American Plant Food Control Officials; Thomas Farmer, Association of American Railroads; Boyd Stephenson, National Tank Truck Carriers; Kyle Liske, Agriculture Retailers Association; Nicholas Cindrich, CVS/Caremark; Howard Kunreuther, University of Pennsylvania; Clare Narrod, University of Maryland; Drew Sindlinger, Nathan Tsoi, and Ramana Kasibhotla, Transportation Security Administration; and Christopher Logue, New York Department of Agriculture.

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
×

Acknowledgment of Reviewers

This Consensus Study Report was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine in making each published report as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process.

We thank the following individuals for their review of this report:

RICK BLASGEN, Council of Supply Chain Management Professionals

RUTH DOHERTY, University of Maryland, College Park

JULIE HECKMAN, American Pyrotechnics Association

NOEL HSU, Orica Limited

MICHAEL KENNEDY, Kennedy Law and Policy

RUSSELL MCINTYRE, Defense Intelligence Agency (retired)

ABDUL-AKEEM A. SADIQ, Indiana University–Purdue University

DWIGHT C. STREIT, University of California, Los Angeles

TIM SWAGER, Massachusetts Institute of Technology

Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations of this report nor did they see the final draft before its release. The review of this report was overseen by JOHN ANDERSON, Illinois Institute of Technology, and FRAN LIGLER, North Carolina State University and Univer-

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
×

sity of North Carolina Chapel Hill. They were responsible for making certain that an independent examination of this report was carried out in accordance with the standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the National Academies.

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
×
Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
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Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
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Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2018. Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals. Washington, DC: The National Academies Press. doi: 10.17226/24862.
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Improvised explosive devices (IEDs) are a type of unconventional explosive weapon that can be deployed in a variety of ways, and can cause loss of life, injury, and property damage in both military and civilian environments. Terrorists, violent extremists, and criminals often choose IEDs because the ingredients, components, and instructions required to make IEDs are highly accessible. In many cases, precursor chemicals enable this criminal use of IEDs because they are used in the manufacture of homemade explosives (HMEs), which are often used as a component of IEDs.

Many precursor chemicals are frequently used in industrial manufacturing and may be available as commercial products for personal use. Guides for making HMEs and instructions for constructing IEDs are widely available and can be easily found on the internet. Other countries restrict access to precursor chemicals in an effort to reduce the opportunity for HMEs to be used in IEDs. Although IED attacks have been less frequent in the United States than in other countries, IEDs remain a persistent domestic threat. Restricting access to precursor chemicals might contribute to reducing the threat of IED attacks and in turn prevent potentially devastating bombings, save lives, and reduce financial impacts.

Reducing the Threat of Improvised Explosive Device Attacks by Restricting Access to Explosive Precursor Chemicals prioritizes precursor chemicals that can be used to make HMEs and analyzes the movement of those chemicals through United States commercial supply chains and identifies potential vulnerabilities. This report examines current United States and international regulation of the chemicals, and compares the economic, security, and other tradeoffs among potential control strategies.

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