Perspective: Iran’s nukesNew Estimates of Iran’s Breakout Capabilities at Declared Sites Using a New, Simple-to-Use Breakout Calculator
A new report from the Institute for Science and International Security (ISIS) presents and applies a breakout calculator to several theoretical cases in which Iran increases its stocks of low enriched uranium (LEU) above the limits allowed in the Iran nuclear deal, or Joint Comprehensive Plan of Action (JCPOA). “During the next many months, breakout times at Natanz and Fordow appear long enough to make an Iranian decision to break out risky,” and, therefore, unlikely, the Institute says. “However, even in the case in which Iran takes no action other than to increase its stocks of up to 3.67 and 4. 5 percent enriched uranium, breakout times could shrink precipitously during the next two years. The potential for relatively rapid decreases in breakout times argues for relatively quick action against Iran’s noncompliance with the JCPOA limits.”
A new report from the Institute for Science and International Security (ISIS) presents and applies a breakout calculator to several theoretical cases in which Iran increases its stocks of low enriched uranium (LEU) above the limits allowed in the Iran nuclear deal, or Joint Comprehensive Plan of Action (JCPOA). In addition, the report develops breakout times for Iran’s August 2019 inventory of LEU.
The report. written by David Albright with Sarah Burkhard, says:
If Iran decided to build nuclear weapons, it could use its existing, declared production-scale gas centrifuge plants, the Natanz Fuel Enrichment Plant and the Fordow Fuel Enrichment Plant, and low enriched uranium already produced there to make weapon-grade uranium (WGU), defined as uranium enriched to at least 90 percent U-235. This report introduces a new, easy-to-use calculator developed by the Institute to evaluate scenarios, commonly called “breakout times,” by which Iran could produce enough WGU for one or more nuclear weapons. In line with previous conventions used by the Institute, 25 kilograms of WGU represents the amount sufficient for a single nuclear weapon.1
In this report, the new breakout calculator estimates realistic, minimum breakout times given Iran’s current enrichment capabilities under the Joint Comprehensive Plan of Action and a set of additional, potential capabilities as it reduces its commitment to the JCPOA’s centrifuge-related limits. Here, with one exception, the focus is on Iran’s potential growth in its stocks of LEU hexafluoride rather than a systematic increase in the enrichment capacity at Natanz and Fordow, in further violation of JCPOA limits. Other scenarios will be addressed in future reports, as events and interests develop.
The report concludes:
During the next many months, breakout times at Natanz and Fordow appear long enough to make an Iranian decision to break out risky. If Iran would quickly increase its breakout capability, it would be more likely to attract UN sanctions snapback or even military strikes. Therefore, the Institute assesses that Iran is unlikely to break out at Natanz or at Fordow in the near term, barring unforeseen developments. It may, however, slowly increase its violations of the JCPOA limits and continue to lower its breakout timelines toward levels that are more threatening.
In terms of shortening breakout times in the next year, the actions that are most provocative are the production of higher enriched uranium (near 20 percent enriched LEU) and possibly the deployment of the stored IR-2m or other advanced centrifuges.
However, even in the case in which Iran takes no action other than to increase its stocks of up to 3.67 and 4. 5 percent enriched uranium, breakout times could shrink precipitously during the next two years. The potential for relatively rapid decreases in breakout times argues for relatively quick action against Iran’s noncompliance with the JCPOA limits.
