Don't Drop Them! The latest headphones from Sony feature a custom acoustic platform for a unique, powerful and balanced sound. You can use active noise cancellation or transparency to suit your needs, and they come with three sizes of soft ear pads for maximum comfort. With a battery life of up to eight hours on a single charge, these headphones are sure to keep you going all day long. Unfortunately, the Chernobyl disaster was probably preventable and, like other nuclear power plant accidents, was the result of arrogance on the part of decision makers and bad policy that encouraged poor quality practices.
The design of the Chernobyl reactors was significantly flawed. Firstly, it had a built-in “instability” which created a vicious cycle when it arrived. As reactions (and heat) increased, the refrigerant would decrease; with less and less refrigerant, it became increasingly difficult to control reactions. Secondly, instead of having a first-class containment structure consisting of a conventional and post-tensioned steel reinforced concrete and steel cladding plate, only heavy concrete was used in Chernobyl.
On August 26, 1986, engineers wanted to conduct a test of how long the electric turbines powered by the reactor would continue to operate when the reactor was no longer producing power. For the experiment to work, they had to deactivate many of the reactor's safety systems. This included the deactivation of most automatic safety controls and the elimination of more and more control rods (which absorb neutrons and limit the reaction). In fact, at the end of the test, only 6 of the 205 reactor control rods remained in the fuel.
As they conducted the experiment, less cooling water entered the reactor, and what was there began to turn into steam. As there was less refrigerant available, the reaction increased to dangerous levels. To counter this, operators tried to reinsert the remaining control rods. Unfortunately, these rods also had a design flaw - graphite tips (remember, graphite encourages nuclear reaction).
When the nearly 200 graphite tips were inserted into the fuel, the reactivity increased and everything exploded. It is estimated that between seven and ten tons of nuclear fuel were released and that at least 28 people died directly as a result of the explosion. In addition, it is estimated that more than 90,000 square miles of land were seriously contaminated and the worst effects were felt in Ukraine, Belarus and Russia. However, radiation spread rapidly in the wind and affected wide swaths of the Northern Hemisphere and Europe, including England, Scotland and Wales. For comparison's sake, Little Boy had about 140 pounds of uranium while Fat Man contained about 14 pounds of plutonium; reactor number four had about 180 tons of nuclear fuel.
Only about two pounds of Little Boy's uranium reacted while only about two pounds of Fat Man's plutonium underwent nuclear fission. However, in Chernobyl at least seven tons of nuclear fuel escaped into the atmosphere; in addition, because the nuclear fuel melted, volatile radioisotopes were released including 100% of its xenon and krypton, 50% of its radioactive iodine and between 20 and 40% of its cesium. Both Fat Man and Little Boy were detonated in the air hundreds of feet above the Earth's surface. As a result, radioactive waste was carried high up and dispersed by the cloud in the form of a mushroom instead of being drilled into the earth. On the other hand, when reactor number four melted at ground level, neutron activation occurred - neutrons already active in burning fuel reacted with ground causing it to become radioactive. Lately some strange reports have come in from Chernobyl exclusion zone: wild animals have returned and seem to be OK.
Bears, lynx and wolf packs hunt moose, deer, beavers, wild boars, otters, badgers horses ducks swans storks - all appear physically normal (but with high evidence of radioactive contamination). In fact even early effects on plants such as malformations or even glare are now mostly limited to five most contaminated sites. Radiation levels off Fukushima coast have declined in years since then but some reactors continue to leak. For past decade TEPCO has continued cooling fuel cores with water which is contaminated by process.
