May 16, 2018


Embarking on their second multi-year phase, the three IPNDV working groups came together in March for a Phase II kickoff meeting in Stockholm to build on the Partnership’s Phase I work identifying potential procedures and technologies to verify the dismantlement of a nuclear weapon.

David Chambers, Rob Floyd, and Jens Wirstam are three of six co-chairs of the three technical working groups:

Technical working groups were established for both Phase I and Phase II to steer and facilitate the work done by the more than 25 countries with and without nuclear weapons that participate in the IPNDV.

Below, David, Rob, and Jens discuss the work underway and what lies ahead for their working groups in Phase II.

How did your working group kickoff Phase II?

David: Working Group 4 (WG4) had an excellent start to Phase II in Stockholm, with a vibrant and thought-provoking range of discussion. WG4 will be looking at the role, objectives and verification of warhead baseline declarations. To do this, we began by addressing the role of declarations of nuclear weapons in disarmament more broadly to understand the importance, requirements, and sequencing of such declarations in relation to agreements to limit, reduce, and eventually eliminate nuclear weapons. We also started to examine lessons on declarations from other regimes, including those from the Chemical Weapons Convention (CWC), the Treaty on Conventional Armed Forces in Europe (CFE), and the Strategic Arms Reduction Treaty (START) family of Treaties.

Rob: Working Group 5 (WG5) focused on deciding how to tackle a systematic analysis of verification requirements across the 14-steps required to dismantle a nuclear weapon.  The steps begin with removal of a weapon from its delivery vehicle at a deployment site and end with nuclear material from weapons being brought under regular non-proliferation safeguards or made practicably irrecoverable.


Jens: Working Group 6 (WG6) focuses on the technologies that can be applied to the various steps and procedures. In Stockholm, our experts gave presentations on technologies, many of which already exist in other contexts outside of nuclear disarmament but could potentially be adapted for this type of work.  We also continued other technical discussions and our work on developing a “toolbox” of potentially applicable technologies at each of the 14-steps.

What are the plans for your working group in Phase II?

David: As we go forward in Phase II, WG4 will continue to explore key elements, concepts, and methodologies from previous regimes to see what may be relevant to include in nuclear weapon declarations, as well as how to verify them. To help understand what we may include in declarations of the weapons themselves—as well as the locations they are in—we have studied the existing literature on descriptors, categories, and types of nuclear weapons to see what is useful to declare and that can be verified. We have also looked at historical weapons facilities to understand what kinds of sites inspectors may be required to visit and what challenges they may face once they are there.

Rob: WG5 will map verification objectives, processes, and techniques for the 14-steps. Our group will also consider the challenges that need to be overcome for inspectors to be satisfied that declared actions have taken place and that there has been no diversion or substitution of nuclear weapons or their components. The group will also consider how the results of inspection should support assessments of compliance with a verification agreement.

Jens:  WG6 will focus on identifying technologies that could potentially be applied at steps 1-5, when the nuclear warhead is removed from the deployed delivery systems and placed into long-term storage, and 11-14, when the fissile material and the high explosives are separated after dismantlement and are disposed of.  The Partnership addressed steps 6-10 during Phase I. Our working group members will prepare papers and presentations that will help us consider different classes of technologies, such as those that support chain of custody and those that detect radiation, that can be used across the steps.

Is there something specific your group is looking forward to in Phase II?

David: WG4 members are looking forward to building on what has been done in the past and to providing a greater understanding of nuclear weapon declarations as well as practical insights into how such baseline declarations can be verified.

Rob: Coordination with WG6 on the technologies required for on-site inspection will be particularly important to us in Phase II. WG5 members also welcome the interest of IPNDV participants to plan and conduct exercises in Phase II, and they look forward to assisting with preparations.

Jens: WG6 members are looking forward to coordinating with and incorporating input from other working groups throughout Phase II.


Read more about the IPNDV working groups here. The next joint working group meeting of the IPNDV will be hosted in South Korea in July 2018.

A version of this article was also published on NTI’s blog, Atomic Pulse