Updated Highlights of Comprehensive Survey of Iran’s Advanced Centrifuges for December 2022 [1]

by David Albright, Sarah Burkhard, and Spencer Faragasso

December 1, 2022

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  • This report summarizes and assesses information in the International Atomic Energy Agency’s (IAEA) quarterly report for November 10, 2022, Verification and monitoring in the Islamic Republic of Iran in light of United Nations Security Council resolution 2231 (2015), including Iran’s compliance with the Joint Comprehensive Plan of Action (JCPOA) and updates issued on November 22 and 29, 2022.

  • Iran continues to deploy advanced centrifuges at its three enrichment facilities at Natanz and Fordow in violation of the limitations outlined in the JCPOA.

  • Under a revived JCPOA, Iran would be permitted to mothball its advanced centrifuges, shortening Iran’s breakout timeline and increasing its ability to build up its capability should the deal collapse or once enrichment capacity restrictions phase out starting in 2025.

  • Iran continues to sideline the IAEA and has significantly reduced its ability to monitor Iran’s complex and growing nuclear program, which notably has undeclared nuclear materials and activities. The IAEA’s ability to detect diversion of nuclear materials, equipment, and other capabilities to undeclared facilities remains greatly diminished. In a recent press conference, as reported by the Jerusalem Post, IAEA Director General Grossi stated there is a “mass of activity about which we don’t know anything.”


  • Since the last quarterly report in September, based on data in the most recent quarterly report, Iran installed 1740 advanced centrifuges, all at the Natanz Fuel Enrichment Plant (FEP). Of these, 1566 are IR-2m centrifuges, organized in nine cascades. The rest were IR-4 centrifuges, in one cascade. These deployments represent a huge jump in the number of installed advanced centrifuges.

  • Iran’s annual deployment rate of advanced centrifuges during this year (November 2021 - November 2022) has increased by over 50 percent compared to the last year (November 2020 - November 2021) and quadrupled from the two years prior combined (November 2018 - November 2020).

  • The origin of the newly deployed IR-2m centrifuges could not be determined. They may have been produced since 2018 or produced prior to 2016. In the former case, Iran may have greatly expanded its advanced centrifuge production rate. In the latter case, Iran would have retrieved them from a secret storage location not declared under the rules of the Joint Comprehensive Plan of Action (JCPOA). The latter case would confirm a long-held suspicion that prior to the JCPOA, Iran had manufactured 3000 IR-2m centrifuges for installation at the FEP but only installed about 1,000 of them, hiding the rest.

  • As of the November 2022 quarterly report, Iran had 4515 advanced centrifuges of all types installed at its three enrichment facilities at Natanz and Fordow as well as 7135 installed IR-1 centrifuges.

  • At the Fordow Fuel Enrichment Plant Fordow (FFEP), Iran has announced the installation of 14 IR-6 centrifuge cascades, where six IR-6 cascades would replace six currently operating IR-1 centrifuge cascades, and result in a total of 16 IR-6 cascades, or 2656 centrifuges, present at Fordow.

  • On November 20, Iran began at the FFEP to use IR-6 centrifuges to produce 60 percent enriched uranium from 5 percent feed. This suggests that Iran continues to experiment with a three-step process towards weapon-grade uranium. Traditionally, a four-step process is used to enrich natural uranium to weapon-grade levels. A three-step process enables Iran to produce weapon-grade uranium in a more compact and efficient manner, making a potential breakout to a nuclear weapon faster. It also suggests that the IR-6 emerged as Iran’s centrifuge of choice for HEU production; a worrisome choice as compared to the IR-1, IR-2m, or IR-4. It is the type it would need fewest of for a secret enrichment plant of high capacity, the type for which few design details are available, and the number of which Iran has made is completely unknown.

  • At its Natanz FEP, Iran intends to install another 18 cascades at the FEP, of which it specified six to be IR-4 centrifuge cascades and six to be IR-2m centrifuges; the remaining six cascades are of yet unspecified type. Installation of these centrifuges has not started as of November 20, 2022.

  • As of November 2022, Iran has exceeded the Institute’s September projection of advanced centrifuge deployments for late 2022, 4440 centrifuges, by 75 advanced centrifuges.

  • Based on new Iranian plans reported by the IAEA on November 22, the Institute projects that Iran now plans on deploying about 4934 additional advanced centrifuges, reaching a total of 9449 advanced centrifuges. Iran did not provide a schedule of deployments and the Institute considers this at least a one or two year deployment plan, based on current understandings of Iran’s ability to manufacture and assemble centrifuges.

  • Iran currently has a total installed nominal enrichment capacity of approximately 24,500 SWU per year, where advanced centrifuges account for 18,000 SWU per year and IR-1 centrifuges account for about 6400 SWU per year. This exceeds for the first time any previously installed enrichment capacity, including before the JCPOA, with only one-quarter of the number of centrifuges.

  • Iran’s installed advanced centrifuge enrichment capacity has exceeded its installed capacity of its IR-1 centrifuges since February 2021 and advanced centrifuges currently account for almost 75 percent of the total installed enrichment capacity.

  • As of November 20, 2022, Iran started to install the fourth of a set of six long-announced cascades of IR-4 centrifuges at Natanz FEP.

  • A centrifuge assembly facility continues to be constructed underneath a mountain near the Natanz FEP, but its startup date remains uncertain, and is unlikely to be operational in 2022 or even 2023.

  • Since June 2022, the IAEA has had no ability to monitor Iran’s centrifuge manufacturing or assembly rate, old or new centrifuge stocks, stocks of critical parts and material, or potential diversion of such stocks or manufacturing capabilities to unknown sites. The IAEA has reiterated its concerns about the completeness of the information it has from Iran and its ability to accurately verify Iran’s declared centrifuges. With Iran accelerating its advanced centrifuge deployments, uncertainties will likely grow in the estimated number of advanced centrifuges produced in excess of those deployed, adding concern to the possibility that Iran will again seek to build a clandestine enrichment plant, using advanced centrifuges manufactured in secret.

Read the full report in pdf here

1. David Albright, Sarah Burkhard, and Spencer Faragasso, “A Comprehensive Survey of Iran’s Advanced Centrifuges,” Institute for Science and International Security, December 2, 2021,

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