Why Is the Islamic Republic Refusing to Admit IAEA Inspectors? S. Rouzbeh ۱۴۰۴/۰۹/۰۴ The absence of reliable technical reporting and full IAEA access after the attacks on Iran’s nuclear sites raises questions about safety, casualties and the risks posed by uranium hexafluoride (UF6). S. Rouzbeh — If “everything is under control”, why has no reliable technical report on the condition of these sites been published since the bombing of Natanz, Fordow and Isfahan? If there was “no leak”, why does the International Atomic Energy Agency say it lacks sufficient information and access to assess the risk? And, most importantly: if no danger threatens the public, why has the government not published figures for the number of people who may have been killed or injured that night, or said how many people were at the sites at the time of the attack? Were the sites really empty, or was it merely claimed that they were? Abbas Araghchi and Rafael Grossi meet in Cairo / September 2025 These questions become more pressing when we consider what substance lies at the heart of these facilities: uranium hexafluoride gas, UF6—the material experts call “the centrifuges’ primary feedstock”, which, if released, can literally act like a chemical-acid bomb. The inspection that went blind at the most critical point After the attacks in June 2025, the IAEA confirmed in an official statement that several Iranian nuclear sites, including Natanz and Isfahan, had been attacked and that, according to preliminary data it had received from Tehran, “radiation levels outside the premises of these facilities show no unusual increase”. The IAEA stresses that, because of restrictions imposed by Iran, it has been unable to carry out a full inspection of all the damaged buildings and has “lost continuity of knowledge” regarding Iran’s inventory of nuclear material; the same point has also been made in independent analyses of the Agency’s report. In effect, the IAEA is saying: “For now, we see nothing outside the perimeter fence, but we have not properly seen inside it.” This is not called a “full inspection”; it is a partial, blind inspection, whose result offers the people of the region nothing but false reassurance. For its part, the Iranian government has still not said how many people were working at each site at the time of the bombing, whether anyone was killed or injured, in which sections injuries occurred, or how many people were tested for chemical and radioactive contamination. When a government is not even willing to say what happened to people in an incident of such significance, how can its claims about gases and cylinders be trusted? What does “hex gas” mean? How is it different from enriched uranium? In discussions of Iran’s nuclear programme, people constantly refer to “hex gas” or “hexafluoride”. This is uranium hexafluoride, with the familiar formula UF6—that is, uranium combined with six fluorine atoms. Two simple but crucial points: “enriched” means that the proportion of the U-235 isotope in the uranium has been increased; “being UF6” means that uranium—whether enriched or natural—has been converted into the chemical form of uranium hexafluoride gas. So enriched uranium and UF6 gas are not two separate things: enriched uranium can circulate through centrifuges as UF6 gas, or later be converted into powder and fuel pellets. New-generation centrifuges have been brought into operation at the Natanz facility to increase uranium enrichment. At Natanz, Fordow and parts of the Isfahan facilities, what circulates through the pipes and centrifuges is UF6. Under normal conditions, this gas is stored in thick steel cylinders; but, as stated in the official UF6 safety data sheet from the US Department of Energy, UF6 reacts rapidly with water vapour as soon as it comes into contact with moisture in the air, producing hydrofluoric acid and toxic fluorine compounds—substances that are extremely dangerous to the lungs, eyes, skin and kidneys. Another safety sheet describes UF6 as “highly toxic, highly corrosive and radioactive”, and stresses that inhalation can cause chemical burns to the respiratory tract, pulmonary oedema and serious kidney damage. In other words, when we talk about “hex gas”, we are talking about a potentially dangerous mixture of acid and radioactive heavy metal which, if its cylinder were broken by an explosion, could act like an invisible chemical-acid bomb. UF6 cylinders: a chemical bomb disguised as an industrial tank Under normal conditions, UF6 is stored and transported in thick steel cylinders. These cylinders are designed to withstand being dropped from a forklift or handled in industrial settings, not to withstand a blast wave and missile fragments. If a bomb explodes near a cylinder, its body may crack or rupture; its valves and flanges may be torn off; and a large volume of UF6 may suddenly be released into the air. Once UF6 escapes the cylinder, it rapidly reacts with moisture in the air, forming acidic gases and toxic particles. Depending on the direction and speed of the wind, this gas cloud can contaminate areas several kilometres around the sites. The IAEA’s technical safety guidance for conversion and enrichment refers precisely to this danger and describes UF6 as a “substance with a high chemical risk”, not merely a source of radiation: the IAEA’s guidance on chemical hazards in the fuel cycle. So when we say that “an enrichment facility is a chemical dirty bomb”, we mean that both the UF6 cylinders and the network of pipes carrying this gas to the centrifuges can, following a military attack, suddenly become sources of acidic gas and contaminated particles being released—with no one hearing a second explosion. Solid uranium: a slower but more enduring danger To give a complete picture, we must also clarify the difference between UF6 and solid uranium. After enrichment, uranium intended for use in a power reactor is turned into powder and then into small pellets, which are placed inside fuel rods. In this form, uranium is no longer a volatile gas; if bombed, it does not create an acidic cloud like UF6; but if crushed into powder, it releases radioactive and heavy-metal particles into the air and soil, which can enter the body through breathing or food. Its danger is more chronic and environmental: soil and water contamination, a long-term increase in certain cancers, and kidney failure. So, in the first few hours and days of an attack on an enrichment facility, UF6 is the main killer; in the longer-term aftermath of damage to solid-fuel storage facilities, the issue is more about contamination of the soil and food chain. This distinction matters to ordinary people, so they can understand why this article focuses on “hex gas” and the cylinders: because in a bombing scenario involving Natanz and Fordow, UF6 is the first thing that takes people’s lives. The world has already paid the price for UF6 leaks The “chemical dirty bomb” is not merely a theoretical scenario invented to frighten people; before Iran, the world saw this nightmare at close quarters. On 4 January 1986, at the Sequoyah Fuels Corporation plant in Oklahoma, a 14-tonne UF6 cylinder ruptured while being heated in a steam chamber. A large quantity of UF6 was released, reacted with moisture in the air, and a cloud of acidic gas and uranium particles settled over the plant and nearby villages. One worker died within the first few hours, dozens of employees were hospitalised, and more than a hundred local residents went to hospital for examination and treatment. The technical report on the incident stresses that most of the harm was caused by the chemical effects of UF6 and hydrofluoric acid, not by a high radiation dose. The Sequoyah Fuels Corporation plant in Oklahoma An earlier example occurred in 1944 at a United States naval facility. A UF6 leak from a cylinder killed two workers; reports there, too, showed that the main cause was chemical burns to the lungs and respiratory tract, not “being burned from within by radiation”. These experiences warn us about one thing: if a single UF6 cylinder can cause such a catastrophe in a country with independent media and institutions, imagine what the same substance could do to people in a country like Iran—with censorship, lies and obstruction of inspections—amid a regional war. Evading transparency: cutting off international help before an accident After the Chernobyl disaster, the international community adopted two important conventions so that no country could hide a nuclear accident behind its borders: the Convention on Early Notification of a Nuclear Accident and the Convention on Assistance in the Case of a Nuclear Accident or Radiological Emergency. Under these instruments, countries have undertaken that if an accident occurs at their nuclear facilities that could also affect other countries, they will immediately inform the IAEA and their neighbours and allow technical, medical and environmental assistance to be provided. In theory, if a serious UF6 leak occurred at Natanz or Isfahan, the IAEA could send specialist teams to monitor the air, water and soil; run advanced models of the spread of the contaminated cloud; and, together with the World Health Organization and other organisations, arrange immediate medical assistance and a long-term health-monitoring programme. In practice, however, by closing the facilities’ doors and cutting off the IAEA’s access, the Islamic Republic has already neutralised this very international support network. The IAEA has repeatedly warned in its statements that continued attacks on Iran’s nuclear facilities and the lack of sufficient information could lead to “very serious radiological consequences”, and has stressed that it needs technical information and access in order to provide any assistance; including in The Director General of the IAEA’s address to the Security Council on the situation in Iran Nevertheless, Tehran is not only failing to provide detailed reports; it is also responding to the Board of Governors’ recent resolutions with threats, effectively saying, “More inspections, less cooperation.” Another danger, sometimes mentioned, is that the Islamic Republic intends to clear the rubble. That is a subject requiring separate discussion and explanation, and it raises this question in the mind. The question On the face of it, clearing debris from the bombed facilities at Natanz and Isfahan means collecting rubble and rebuilding structures. In reality, however, every excavator and every cut into a pipe or cylinder could release pockets of residual UF6 gas and its by-products, such as HF and toxic deposits on soil and concrete, sending small but highly dangerous chemical clouds and contaminated dust into the air. At this stage, it is above all the workers and technical staff inside the site who are exposed to chemical burns to the lungs and chronic contamination. If the work is carried out without a safety plan, environmental monitoring and independent oversight—including the presence of the Agency—debris clearance could effectively create a new disaster: a silent one that later manifests only as increased illness and cancer in those same areas. At the end of this picture, several simple but weighty questions remain on the table: If there is no leak or danger, why does the Islamic Republic not permit a full inspection, with the Agency present and a public report issued? If nobody was killed or injured at the sites during the attacks, why not publish a breakdown of the figures and the results of medical tests to put people’s minds at ease? If the danger posed by UF6 is so much a “media delusion”, why do official safety data sheets in the United States and Europe classify this gas as “highly toxic and corrosive”, with a serious risk to the lungs and kidneys? And why have historical incidents such as the Sequoyah Fuels accident shown that, even without a war, a single UF6 cylinder can claim dozens of victims? And most importantly: in a calculation with a “nuclear programme” on one side and “the right of millions of people to breathe” on the other, who gave this government the right to erase the problem instead of managing the danger scientifically, leaving people under the shadow of a chemical dirty bomb? So long as these questions remain unanswered and the doors of Natanz, Fordow and Isfahan remain closed to genuine inspections and public reporting, one truth does not change: Iran’s enrichment facilities, in their present condition, are less “symbols of progress” than chemical dirty bombs whose risk of silent detonation is recalculated every day, with each new crisis. And if disaster strikes, it will once again be ordinary people—from Kashan, Natanz and Isfahan to the surrounding villages—who pay with their lives and health, despite having had no seat at any negotiating table. Source: https://srouzbeh.com/en/posts/archive-657bea6f-42d7-0d87-1590-200242d658e8 Please credit the author and link to this edition.