Learn about our world class

High-Altitude Electromagnetic Pulse (HEMP/EMP)

High-Altitude Electromagnetic Pulse (HEMP) and IEMI (Intentional Electromagnetic Interference) are two special electromagnetic threat/mitigation scenarios. A HEMP is the result of a nuclear detonation at an altitude greater than 30 miles. The electromagnetic field generated by the effects of gamma rays interacting with the atmosphere at approximately 15-30 miles in altitude is what is referred to as an “Electromagnetic Pulse”. Such a pulse can be very intense (50,000 V/m) and very broadband, subjecting a variety of electronics and power and other infrastructure to potential damage.

Many military systems have already been hardened for EMP through design or the creation of special shielded environments suitable for military operations. However, Civil Infrastructure is still very vulnerable to damage from an EMP.

Mitigation of EMP effects is a complex undertaking, and the specific actions taken will depend upon equipment or facility criticality, size, geographic span, and interconnections.

Military systems are often enclosed in a fully-shielded environment composed of a highly conductive material (often steel) with penetrations specially designed to accommodate function with RF shielding.

Clipboard01This is generally not an approach that fits most Civil Infrastructure. For instance, a power system includes generation stations, transmission lines, substations, and distribution infrastructure. There is no sensible way to completely shield such a geographically dispersed system. Mitigation of such a complex system must utilize measures such as logistical spares, redundancy, and critical subsystem hardening to minimize damage and downtime to the overall system functionality.

FMS provides EMP consultation services around the world to assist in mitigating the increasing threat of EMP and IEMI to civil infrastructure around the world.

Our services include:

  • Design of EMP/IEMI shielding to meet equipment and system performance specifications.
  • Design of cost-effective mitigation measures to increase the resilience of Civil Infrastructure systems to EMP/IEMI.
  • Vulnerability Assessment of Civil Infrastructure systems to EMP/IEMI threats.
  • Testing of critical Civil Infrastructure subsystems to determine their hardening requirements.
  • Installation of EMP/IEMI Mitigation, including EMP/IEMI shielding.

FMS has extensive experience with all aspects of electromagnetic protection from the impact of EMP/IEMI threats. FMS’ staff have experience developing unique mitigation approaches and have collaborated closely with experts and clients around the globe in the design and implementation of civil infrastructure resilience that matches the electromagnetic threats that are likely to be encountered. FMS staff have “written the book” on EMP hardening measures for civil infrastructure in collaboration with experts around the world.

Recent Projects


FMS as the EMF/EMI Consultant designed and installed the passive and active mitigation systems for this newly established interdisciplinary organization under the Office of Research of the University of California Irvine (UCI) to house state of the art electron-microscope labs (4 imaging cells). The project required analysis of interference potential of all internal and external emission sources, which included vehicle and facility elevators (DC), broadband electrical system (AC) sources, etc.

Harvard LISE

FMS was engaged as the project’s EMI Consultant by the project architect (Wilson Architects) to conduct an electromagnetic field (EMF) analysis in an existing laboratory (shell space) located in the basement level of the Harvard CNS facility.


Seattle Children’s Research Institute is currently in the construction phase of ”Building Cure”, a 540,000 square foot research building, which will be dedicated to developing therapies for children with diseases such as Cancer, Type 1 Diabetes and Sickle Cell Anemia.

Un. of Illinois Urbana-Champaign Electrical and Computer Engineering Bldg.

FMS was engaged to conduct a thorough assessment of the building’s design for EMI interference threat concerns to sensitive research equipment. A document review and extensive 3-Dimension computer simulation studies were conducted to evaluate EMF emissions from the building’s electrical distribution, mechanical and other systems.


Over its 20 years, FMS has successfully completed hundreds of EMI projects which included a diverse range of consulting and mitigation services.

Take a look at a list of the markets we serve »