What are the risks of bombing a nuclear site?

American war planes bombed three nuclear sites in Iran, the same places as Israeli aircraft had targeted in its current war with Iran.

One of the targets was Fordo, a uranium enrichment factory hidden in a distant mountain flank which is vital for Iran’s nuclear ambitions.

The main nuclear installations of Natanz and Isfahan were also affected.

It is not yet clear how much damage has been caused to the installations, although the UN nuclear custody said that there had been “no increase” of the outstanded radiation levels reported.

But what do we know about sites and what are the risks of attacking nuclear installations?

The IAEA described Israel’s attacks on Iranian nuclear installations as “deeply concerning”.

Last week, its general manager Rafael Grossi said that military climbing “increases the chances of radiological release with serious consequences for people and the environment”.

Uranium enrichment sites are used to create supplies of a particular type – or isotope – uranium.

“When you dig uranium out of the ground, it presents itself in two forms: 99.3% is uranium-238-and 0.7%, or approximately an atom in 150, is uranium-235, and that is what you need to work in your nuclear reactor”, explains Professor Paddy Rejea of ​​the University of Surrey and the physical laboratory of the United Kingdom.

The nuclear enrichment process essentially means increasing the amount of uranium-235.

This is done by taking uranium in its gas form and spinning it in machines called centrifugal, said Professor Regan.

And because uranium-238 is heavier than Uranium-235 required, the two separate when they turn. This is repeated again and again to stimulate enrichment.

Nuclear power plants generally need around 3 to 5% of this enriched uranium to generate a controlled nuclear reaction that releases energy.

But when the objective is to make a nuclear weapon, a much higher proportion of uranium -235 is necessary – around 90%.

Essentially, the more enriched uranium, the greater the burst of energy when all these atoms are divided.

The IAEA said that Iranian uranium had reached around 60% enrichment – so on the point of being concentrated enough for a nuclear weapon.

But shooting a rocket on properly stored stocks of enriched uranium would not pose a “nuclear incident” on the same scale as the disasters that occurred in nuclear power plants in Fukushima or Chernobyl.

“Highly enriched uranium is about three times more radioactive than uranium not enriched. But in fact, at the level of things, none of them is particularly densely radioactive. This would not cause a major environmental contamination problem”, explains Professor Jim Smith, of the University of Portsmouth, who studied the afternoon of the Chernobyle catastrophe.

“We are more concerned with what we call fission products – things that uranium is distributed when it is in a reactor or in a bomb – things like radioactive cesium, radioactive strontium, radioactive iodine. They are more a problem of environmental contamination.”

But because no nuclear reaction takes place on enrichment sites – and an explosion of a bomb would not trigger one – these dangerous radioactive “fission” products would not be present, he said.

Instead, uranium could be dispersed locally by an explosion.

The IAEA said that there had been no increase in out -of -site radiation levels “reported after the American attacks. Last week, when Isreal struck the installation of Natanz, the IAEA found radioactive contamination on the site, but they said that the outdoor radioactivity levels remained unchanged and at normal levels.

“With uranium … The influence does not travel really far,” said Professor Claire Corkhill, president in mineralogy and radioactive waste management at the University of Bristol.

But for people close to the site, there could be health risks, she said.

“In terms of toxicity for the human body, you certainly don’t want to breathe in uranium particles and you don’t want to ingest them either,” she said.

“It is because uranium particles could be housed in the cells, inside your lungs or your stomach, and slowly, radioactive decomposition, and this will cause damage.”

In addition to radioactivity, chemical exposure could also be a problem for anyone nearby.

“If there was an incident and centrifuges were to release uranium hexafluoride, the gas contained in centrifugal, then it would be a truly serious chemical incident,” said Professor Simon Middleburgh, nuclear materials scientist, from the University of Bangor.

“If this uranium hexafluoride comes into contact with humidity in the air, it is really quite corrosive and nasty because it can form this very, very strong acid,” he said.

“But that will not have a massive environmental impact beyond the very, very local area.”

The IAEA said that its incident and its emergency center had worked 24 hours a day. The United Nations agency said it would provide other assessments on the situation in Iran as you are available.