A new era for Light Initiated High Explosives and weapons testing

In response to the nation’s evolving nuclear deterrence needs, Sandia upgraded and expanded the 60-year-old Light Initiated High Explosives facility. The Labs and NNSA unveiled the improved facility during a ribbon-cutting ceremony on March 11.

From the 1970s until the unofficial end of the Cold War in 1992, the facility was used for impulse testing the nuclear weapons stockpile. Although it closed near the end of the Cold War, Sandia predicted a future need for Light Initiated High Explosives testing and funded the team for six months to document processes and store critical equipment. The facility was dark from 1992 to 2001, used mainly for storage and to operate the testing-related environmental permit.

After a significant renovation of the facility began in 2001, the original Light Initiated High Explosives team returned to mentor and train the next generation of team members, then recommissioned the facility in 2002.

Sandia stored critical equipment, documented test processes, maintained the necessary environmental permits and made available the original subject matter experts to ensure a viable restart of this critical capability required to qualify the W76-1 warhead.

Since then, the facility has been at the forefront of qualifying reentry systems for the nuclear security enterprise. An emerging need to conduct impulse testing on live internal explosives informed a development proposal in 2010, a conceptual design study in 2015 and a defined requirement for the W87-1 warhead in 2019.

Construction and operational resilience

The construction contract for the upgraded facility, known as the Light Initiated High Explosives Annex, was awarded in February 2023, with the final temporary certificate of occupancy received in February 2025. Remarkably, this project was completed alongside ongoing explosive tests, including a critical qualification test for the W87-1 warhead, demonstrating the facility’s operational resilience.

Because of the smooth collaboration among the LIHE team, Facilities, ES&H, Security and Summit Construction, the groups were able to conduct two years of scheduled explosive impulse tests while simultaneously managing a major construction project. In all, nine major tests were executed as the construction project was being completed.

The Light Initiated High Explosives Facility is the only test site that can simulate system-level, radiation-induced shock loading from a hostile nuclear encounter beyond the Earth’s atmosphere. This mechanical shock uses a specialized primary explosive that is simultaneously detonated using an intensive flash of light from a 40-kilvolt, 150-kiloampere capacitor bank. The recent facility expansion increases the facility’s explosive testing capability from the equivalent force of 1 to 50 pounds of TNT, providing vital structural response data on live internal high explosive in this hostile environment.

A commitment to safety and future capabilities

From construction and environmental, safety and health perspectives, the annex project involved complex modifications to a facility with a 60-year history. The project resolved legacy issues and ensured compliance with current codes and standards while continuing operations throughout construction. Effective coordination between testing and construction activities was essential, particularly given the hazardous nature of operations. The design also had to accommodate regulatory compliance, with significant contributions from various safety and security teams.

“LIHE is another step forward in advancing Sandia’s mission by delivering the unique capabilities our nation relies on. Attending the facility’s ribbon cutting filled me with immense pride and optimism for Sandia’s future,” Associate Labs Director for Infrastructure Operations Jeff Heath said. “With its dramatic enhancement in capability, LIHE sets a new standard for the nuclear security enterprise by offering an unparalleled simulation environment for reentry systems. I am truly humbled to be part of the dedicated team that brought this visionary capability to life.”

The project’s successful completion highlights a strong partnership between Sandia and NNSA. The project presented safety considerations, requiring design solutions beyond standard codes. The NNSA Sandia Field Office played a critical role in approving the alternate design and technical security aspects necessary for the facility. Funding for construction and readiness efforts was secured through specific program allocations, highlighting the collaboration that made this project possible.

Steve Girrens, associate Labs director for Nuclear Deterrence Components and Production, spoke at the ribbon-cutting ceremony about his passion for the project and his excitement about the future of the facility.

“The successful completion of the LIHE Annex project achieved a very significant milestone for ensuring the environmental qualification of our weapon systems today and into the future,” he said.