Of concern are high-level electromagnetic fields that will create serious problems for electronic systems on the Earth’s surface, including critical infrastructure.
Dr. William A. Radasky, Ph.D., P.E.
Metatech Corporation, Goleta, CA
Over the past seven years, a substantial number of articles have been written by this author and others identifying the threat and importance of intentional electromagnetic interference (IEMI).[1–7] Work continues steadily in this area, although not as rapidly as last year when a large number of EMC conferences and special sessions were held.
In 2006 after the Zurich EMC Conference held in Singapore, the major conference for this topical area was the AMEREM Conference in July 2006 in Albuquerque, New Mexico. This is the major conference in the world dealing directly with high power electromagnetic environments, effects, and protection, including IEMI and all types of nuclear EMP. A few important papers and topics will be mentioned in this article.
A second area to be discussed in this article is the work of the Congressional EMP Commission in the United States. They completed the first portion of their work in 2004 by describing the HEMP threat to the U.S. infrastructure, and they took up their work again in May of 2006 to review the response to their initial report and to encourage those responsible for the critical infrastructure to develop mitigation methods to deal with the threat. The original findings of the commission will be reviewed here.
A third area of work includes the activities of SC 77C of the International Electrotechnical Commission (IEC) in Geneva, Switzerland. This subcommittee of the EMC committee within the IEC, has prepared 17 standards and reports dealing with the high-altitude electromagnetic pulse (HEMP) and other high power electromagnetic (HPEM) threats such as IEMI on civil systems. Meetings of the project teams of SC 77C were held in Albuquerque in July 2006 and in London in February 2007. This paper will discuss the status of the work to date.
To refresh the reader regarding the terminology employed here, the term IEMI refers to the deliberate attempt to produce electromagnetic radiated and/or conducted disturbances to interfere with the operation of commercial equipment. This could be done for criminal or terrorist purposes, although the purpose of the technical work is to determine the feasibility of such attacks, to determine ways to detect an attack, and/or to protect against the types of disturbances that might be generated.
The terminology of the electromagnetic pulse has evolved over the years, but today the generic term for all types of nuclear generated electromagnetic transients is EMP. Sometimes one will see the term NEMP, which clearly identifies the particular pulse of interest as being generated by a nuclear detonation. Of interest here is the EMP created by a high-altitude burst, generally defined as one occurring at a burst height greater than 30 km. At this altitude, the radiation produced by the nuclear burst would not reach the Earth’s surface, but several types of intense electromagnetic signals would. Because the burst is at high altitudes (in space), this type of EMP is usually referred to as HEMP. The concern is that these high-level electromagnetic fields will create serious problems for computers and other electronic systems on the Earth’s surface, including the critical infrastructure (power, telecommunications, transportation, finance, water, food, etc.). This is the focus of the EMP Commission in the United States and the IEC subcommittee 77C in Geneva.
JOINT IEEE APS/URSI/AMEREM SYMPOSIUM (9–14 JULY 2006)
This conference was held in Albuquerque, New Mexico, and as indicated above, it was a joint conference between three organizations, all dealing with electromagnetics. The AMEREM portion of the conference dealt exclusively with high power EM aspects including: electromagnetic pulse (EMP) threats, effects, and protection; high-power microwave (HPM) threats, effects, and protection; wideband threats, effects, and protection; simulator design techniques; measurement methods; and numerical methods.
In the plenary session, two overview papers were presented covering the IEMI and HEMP threats:
- V. Fortov, Yu. Parfenov, L. Siniy, L. Zdoukhov, “Russian Research of Intentional Electromagnetic Disturbances Over the Past Ten Years.”
- W. Radasky, “Overview of the Published Work of the U.S. EMP Commission.”
During the AMEREM Conference, there were many important papers presented covering the susceptibility of electronic components and equipment to different types of transient EM waveforms, ranging from narrowband to hyperband. As a better understanding is derived from the impact of IEMI waveforms on various types of electronic systems, we will be able to develop mitigation methods to deal with these new threats.
THE U.S. CONGRESSIONAL EMP COMMISSION
In 2003, the U.S. Congress formed a commission to study the possible effects of EMP on the United States. The Commission was chaired by Dr. William R. Graham. In particular, the charter asked the committee to:
- Assess the EMP threat (from a high-altitude detonation) to the United States including the nature and magnitude of EMP threats within the next 15 years from all potentially hostile states or non-state actors.
- Evaluate the vulnerability of U.S. military and especially civilian systems.
- Determine the capability of the U.S. to repair and to recover from damage to military and civilian systems.
- Examine the feasibility and cost of EMP hardening select military and civilian systems.
- Recommend protection steps the U.S. should take.
As part of their study, they examined the historical record of information including data from high-altitude nuclear tests performed by the United States and the Soviet Union in 1962, and they directed research to evaluate the susceptibility of today’s critical infrastructure.
Figure 1 illustrates a photograph taken from Honolulu, Hawaii during the evening of July 9, 1962 when the U.S. Starfish Event took place. This event consisted of a 1.4 megaton device detonated at an altitude of 400 km at a distance of 800 nautical miles from Honolulu. At the time of the test, some malfunctions of the Hawaiian street lights were noted (some lights were extinguished), and microwave communications were also disrupted. Other impacts such as burglar alarms being set off were noted; however, it should be recalled that the level of electronics involved in the infrastructure nearly 50 years ago is a far cry from today’s digital world. The EMP Commission report also mentions that there was an unexpected collateral effect during this test, and that was that a number of satellites were damaged during the test and over the next 6 months because of the creation of a new temporary space radiation belt.
While the EMP Commission studied all major aspects of the critical infrastructure, they determined that the power system was the most critical because of its connection to all of the other major infrastructures such as communications, transportation, emergency services, energy distribution, water/food, etc. After considerable study the commission concluded:
- HEMP-induced functional collapse of the electrical power grid risks the continued existence of U.S. civil society.
- Early-time HEMP transients are likely to exceed the capabilities of protective safety relays.
- Late-time HEMP could induce currents that create significant damage throughout the grid.
- The national electrical grid is not designed to withstand near simultaneous functional collapse.
- Procedures do not exist to perform “black start” after an EMP attack as restart would depend on telecom and energy transport, which depend on power.
- Restoration of the national power grid could take months to years.
- HEMP-induced destruction of power grid components could substantially delay recovery.
The Commission’s overall power system conclusion was: “Widespread functional collapse of the electric power system in the area affected by EMP is likely.” One of the aspects of the power grid studies performed by the Commission included the recognition that the late-time portion of the HEMP and the electromagnetic fields produced at the Earth’s surface by intense geomagnetic storms are very similar in terms of duration and impact on the high-voltage power grid. Since a severe geomagnetic storm in March 1989 created a blackout in the Hydro-Quebec power grid caused by the injection of large quasi-dc currents into the AC transmission system, it is clear that this type of disturbance has the capability to shut down a power grid. Figure 2 illustrates the level of magnetic field disturbance at the time of the power outage in Quebec. Note that while the environmental disturbance was the highest near Winnipeg at that time, the efficient coupling of the fields to the long power lines operating at 765 kV north of Montreal was the main reason that the outage affected only Quebec.
The EMP Commission describes in detail many facets of the HEMP threat to the infrastructure in their Executive Summary Report , and it concludes with the following statements:
- The HEMP threat is one of a few potentially catastrophic threats to the United States.
- By taking action, the HEMP threat can be reduced to manageable levels.
- U.S. strategy to address the HEMP threat should balance prevention, preparation, protection, and recovery.
- Survivability and durability in critical military capabilities are essential factors underwriting U.S. strategy.
IEC SC 77C (EMC: HIGH POWER TRANSIENT PHENOMENIA)
Considering the published work of the EMP Commission and its continuing efforts to ensure that steps are taken to deal with the HEMP problem, it becomes clear that the protection of the civilian infrastructure from this severe electromagnetic threat is more important than ever. Since 1989, the International Electrotechnical Commission (IEC) headquartered in Geneva, Switzerland has been publishing standards and reports dealing with the HEMP and IEMI threats and methods to protect civilian systems from these threats under SC 77C (High Power EM Transients). As these are electromagnetic threats, it was decided from the outset that this effort would be closely integrated with the EMC work being performed by the IEC and other organizations throughout the world. In fact, IEC Technical Committee 77 has the title of “EMC”.
Figure 3 illustrates the entire list of publications produced by IEC SC 77C, and they are numbered according to the numbering scheme developed for all EMC publications of the IEC. Of the documents listed in Figure 3, those shown in orange deal with high power EM aspects including IEMI. The others deal mainly with HEMP although some of the publications dealing with mitigation and protection are general to many types of EM transients. The reader is invited to go to the IEC website for additional information ( www.iec.ch).
For a clearer understanding of the HEMP threat, consider IEC 61000-1-3, a report that describes the effects of HEMP on systems that were noted and published in the past. IEC 61000-2-9 is a standard that describes the HEMP radiated environment, and it is important to recognize that there are three distinct pulses that are emitted from the same nuclear detonation at high altitudes. Each of these can vary depending on burst height and weapon design, but Figure 4 from 61000-2-9 illustrates the HEMP protection design waveforms recommended for consideration and study. The conducted environment is presented in IEC standard 61000-2-10, and it describes the levels of currents and voltages that can be induced by the radiated fields on elevated and buried cables such as power lines on bulk communications cables. Figure 5 from 61000-2-10 illustrates the early-time (E1) currents that could be coupled to randomly oriented cables on a statistical basis.
While these three publications give a good introduction to the standards of the IEC dealing with HEMP, space does not permit a complete discussion of the other documents. It should be noted that there is enough information in the documents illustrated in Figure 3 to describe most commercial facilities in a general way and then, to determine the protection requirements and test methods needed for testing and protecting those facilities against the HEMP threat. The IEC is currently working on two new projects dealing specifically with the protection of the infrastructure from the HEMP threat and on more detailed procedures to assess the threat of HEMP for different types of systems. Also, several companies including Metatech and QinetiQ are developing procedures to apply these IEC standards in a coordinated way to allow industry to mitigate the effects of HEMP.
For additional information about the HEMP or IEMI work in the IEC, please contact either the Chairman of SC 77C, William Radasky ([email protected]) or the Secretary of SC 77C, Richard Hoad ([email protected]).
- W.A. Radasky, “What Is Intentional Electromagnetic Interference (IEMI) and What Can We Do About It?” ITEM Magazine, April 2003.
- W.A. Radasky, “An Update on Intentional Electromagnetic Interference (IEMI).” Interference Technology Annual EMC Guide, April 2004.
- W.A. Radasky, “2005 Update on Intentional Electromagnetic Interference (IEMI),” Interference Technology EMC Directory and Design Guide, April 2005.
- W.A. Radasky, “2006 Update on Intentional Electromagnetic Interference (IEMI),” Interference Technology EMC Directory and Design Guide, April 2006.
- W.A. Radasky, M.A. Messier, M.W. Wik, “Intentional Electromagnetic Interference (EMI) – Test Data and Implications,” 14th International Zurich Symposium and Technical Exhibition on EMC, February 2001.
- W.A. Radasky, M.W. Wik, “Intentional Electromagnetic Interference (IEMI) – Understanding the Threat and Developing Protection Concepts,” 15th International Zurich Symposium and Technical Exhibition on EMC, February 2003.
- William A. Radasky, Carl E. Baum, Manuel W. Wik, “Introduction to the Special Issue on High-Power Electromagnetics (HPEM) and Intentional Electromagnetic Interference (IEMI),” IEEE Transactions on EMC, Vol. 46, No. 3, August 2004, pp. 314-321.
- “Report of the Commission to Assess the Threat to the United States from Electromagnetic Pulse (EMP) Attack,” Vol. I: Executive Report, 7 April 2004.
William A. Radasky received the B.S. degree with a double major in Electrical Engineering and Engineering Science from the U.S. Air Force Academy in 1968. He also received the M.S. and Ph.D. degrees in Electrical Engineering from the University of New Mexico in 1971 and the University of California, Santa Barbara in 1981, respectively.
He started his career as a research engineer at the Air Force Weapons Laboratory in Albuquerque, New Mexico working on the theory of the electromagnetic pulse (EMP). In 1984 he founded Metatech Corporation in Goleta, California where he is currently President and Managing Engineer. During his 38-year career, he has published over 350 technical papers and reports dealing with electromagnetic interference (EMI) and protection.
Dr. Radasky’s current interests include studies to understand the threat of Intentional EMI and to develop mitigation and monitoring methods to protect facilities from this new threat. He is Chairman of IEC Subcommittee 77C, which is developing high-power electromagnetic protection and test standards for civil systems. He is also the Chairman of TC-5 (High Power EM) for the IEEE EMC Society. Other IEMI activities include his role as Associate Editor for the IEEE EMC Transactions special issue on IEMI in 2004 and as chair of the IEEE Standards Working Group to provide protection guidelines for publicly accessible computers from the threat of IEMI. In addition he is the Chairman of the IEC Advisory Committee on EMC (ACEC), which is tasked to coordinate all EMC standardization work for the IEC. He is an EMP fellow and a member of the Eta Kappa Nu and Tau Beta Pi honor societies. In October 2004 he was presented the Lord Kelvin Medal in Seoul, South Korea by the International Electrotechnical Commission for exceptional contributions to international standardization.