![]() The various levels of containment are very strong and not easily penetrated. ![]() It also needs to be pointed out that there is a fundamental difference between the causes of the Chernobyl and Fukushima reactor releases and any potential breaching of containment using munitions. The type of reactor is different and the potential failure modes are also different. Professor Malcolm Sperrin, Director of the Department of Medical Physics and Clinical Engineering, Oxford University Hospitals NHS Trust, said: 1% may not sound much, but in normal operation a 1 GW electrical output reactor is generating about 3 GW of thermal (heat) energy, so this is about 30 MW – the equivalent of about 30,000 or so 1 kilo Watt little electric heaters/radiators!!” Although it varies over time, this equivalent of “dying embers” emits of order 1% of the reactor’s full power over a longish timescale. This is due to radioactive products built up in the fuel due to its earlier operation, and is called “decay heat” (this can be likened a bit to the dying embers of a fire, after a fire has been put out). after the chain reaction has been ceased). “The need for cooling persists even after the reactor has been shut down (i.e. Damaging certain cooling systems could also prevent the reactor from properly cooling itself and lead to overheating – a “meltdown”. Similarly with any radioactive waste stores on site. Hitting the fuel cooling ponds (whilst fuel is in them) could cause a radioactive dispersion. “However, a nuclear incident might be caused by other things besides a strike on the reactor itself. It’s important to note that this would not trigger a nuclear explosion from the nuclear material itself (so it doesn’t further detonate, like a chemical explosive might do – nuclear fission works in a different way to that). “Danger from a missile hitting a reactor is the potential for release of the radioactive inventory (inside of the reactor) itself. So for example following Chernobyl most of the radioactive material went to Ukraine itself, Belarus, and Russia. “Whilst it’s very uncertain what might happen in such an event (you could have a small release or large release, and winds could preferentially blow things one way or another), clearly the places closest by would likely be the most affected. The source term means the actual amount and nature of the radioactive release, which would be highly dependent on the scale and specifics of the damage caused (for example at Chernobyl the explosion, caused by it being a bad/unstable design, blasted a plume into the air – whereas at Fukushima there wasn’t the same power to send things over a wide range). ![]() “In a nuclear incident much depends on the “source term” and prevailing conditions (the latter being mostly the weather). However, nothing is indestructible, and sufficiently powerful and sustained targeted attacks would eventually break through. They are designed to withstand aircraft impact, earthquakes, explosions, and similar. These are a concrete containment (metres thick of concrete) and a steel pressure vessel (just under a foot thick of steel) as well as the fuel’s casing. “Most nuclear reactors, such as the ones at Zaporizhzhia, have a number of strong protective barriers to prevent radioactive release. Professor Paul Norman, Professor of Nuclear Physics & Nuclear Energy, University of Birmingham, said: ![]() There have been a number of media reports on Russia’s claims that the occupied Zaporizhzhya nuclear power plant in Ukraine could spread dangerous radiation across eastern Europe. Expert reaction to Russian claims that a Zaporizhzhia nuclear power plant accident could spread radiation across parts of Europe
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