Menzingen Verification Experiment

Verifying the Absence of Nuclear Weapons in the Field

In March 2023, UNIDIR conducted the Menzingen Verification Experiment to test procedures for confirming the absence of nuclear weapons at storage sites.

Organized in partnership with the Swiss Armed Forces, Spiez Laboratory, Princeton University’s Program on Science and Global Security, and the Open Nuclear Network (ONN), and supported by the Governments of the Kingdom of the Netherlands, Norway, and Switzerland, the project simulated an inspection at a former air defence site near Menzingen, Switzerland.

UNIDIR developed a model inspection protocol and techniques to verify inspected site's non-nuclear-armed status. Commercial satellite imagery was acquired to aid monitoring. The scenario assumed the inspection verified compliance with an agreement to remove nuclear weapons from bases with delivery systems. Procedures were modelled on existing arms control agreements.

This experiment provided valuable practical experience while identifying challenges and new approaches to strengthen verification.

Read the full report on UNIDIR's website.