EMP THREATProtecting National Public Warning System from EMPs

Published 8 September 2022

DHS released a report of operational approaches to protect the National Public Warning System from an electromagnetic pulse (EMP). The report summarizes recommendations that federal, state, local agencies, and private sector critical infrastructure owners and operators can employ to protect against the effects of an EMP event.

The Department of Homeland Security (DHS) released a report of operational approaches to protect the National Public Warning System from an electromagnetic pulse (EMP). The report is a collaborative effort between the DHS Science and Technology Directorate (S&T), the Federal Emergency Management Agency (FEMAIntegrated Public Alert and Warning System (IPAWS) Program, and the Cybersecurity & Infrastructure Security Agency (CISA). The report summarizes recommendations that federal, state, local agencies, and private sector critical infrastructure owners and operators can employ to protect against the effects of an EMP event.

“Electromagnetic pulses, whether caused by an intentional EMP attack or a naturally occurring geomagnetic disturbance from severe space weather, could disrupt critical infrastructure such as the electrical grid, communications equipment, water and wastewater systems, and transportation modes,” said Kathryn Coulter Mitchell, DHS Senior Official Performing the Duties of the Under Secretary for Science and Technology. “This could impact millions of people over large parts of the country. It is critical to protect against the potential damage an EMP event could cause.”

The National Public Warning System ensures the President of the United States can communicate with Americans in the event of a national emergency. The FEMA IPAWS Program equips 77 private sector radio broadcast stations with EMP-protected backup transmitters, communications equipment, and power generators that would enable the station to broadcast national emergency information to the public in the event of an EMP event.

“These stations represent a key public-private sector partnership and serve as the primary sources for a national emergency broadcast during a catastrophic disaster,” said Antwane Johnson, FEMA IPAWS Program Director. The stations are located across the country providing radio broadcast coverage to more than 90 percent of U.S. population. 

As part of a broader DHS effort to ensure critical infrastructure and emergency response systems are protected against EMPs, FEMA conducted high-altitude electromagnetic pulse (HEMP) testing on the NPWS equipment to evaluate its operational resiliency. The testing confirmed the effectiveness of protection for NPWS stations, showing they could withstand the effects of an EMP in accordance with military specifications.

“Protecting critical assets from EMP is part of a larger DHS effort to assess and mitigate EMP risk in both the public and private sector,” said Acting CISA Assistant Director Mona Harrington. “CISA remains committed to working with our partners to implement requirements outlined in the Executive Order on Coordinating National Resilience to Electromagnetic Pulses, which strengthens our nation’s preparedness from EMP.”

DHS says that the best practices and design principles noted in the Electromagnetic Pulse Shielding Mitigations report can be implemented by critical infrastructure owners and operators who seek to secure their assets against EMP in a similar manner to the NPWS equipment.

CISA works with government and industry partners to execute the Department’s EMP/GMD Strategy. For more information on these efforts and associated resources, visit DHS Combats Potential Electromagnetic Pulse (EMP) Attack.