Monthly Archives: March 2011

Helicopters Dropping Water on Affected Reactors

UPDATE AS OF 9:00 P.M. EDT, WEDNESDAY, MARCH 16: Crews began aerial water spraying operations from helicopters to cool reactor 3 at Fukushima Daiichi shortly before 9 p.m. EDT on Wednesday, March 16. The operation was planned for the previous … Continue reading

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Introduction to Radiation Health Effects and Radiation Status at Fukushima

What is radiation? Where does it come from and what is it used for? Radiation is energy that propagates through matter or space. Radiation energy can be electromagnetic or particulate. Radiation is usually classified into non-ionizing (visible light, TV, radio … Continue reading

Posted in Fukushima, Radiation Protection

News Updates and Current Status of Facilities

Units 1 and 2: TEPCO has released estimates of the levels of core damage at these two reactors: 70% damage at Unit 1 and 33% at Unit 2. They have also stated that Unit 1 is being adequately cooled. Outlook: … Continue reading

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What is Decay Heat?

Explanation of Nuclear Reactor Decay Heat Nuclear reactors produce electricity in a similar way to conventional coal plants in that they heat steam to drive a turbine that spins an electric generator.  However, they differ on how that heat is … Continue reading

Posted in Basics

What are Spent Fuel Pools?

Spent nuclear fuel pools Spent nuclear fuel (SNF) refers to fuel after it has fueled a reactor.  This fuel looks like new fuel in the sense that it is made of solid pellets contained in fuel rods.  The only difference … Continue reading

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Unit 2 Explosion and Unit 4 Spent Fuel Pool Fire

Explosion at Unit 2 It was reported earlier today that the explosion at Unit 2 of the Fukushima Daiichi plant damaged the suppression chamber.  As discussed in the previous post, the suppression chamber/torus (i.e. donut shape vessel containing water) is … Continue reading

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Explanation of Hydrogen Explosions at Units 1 and 3

Explosions at units 1 and 3 occurred due to similar causes. When an incident occurs in a nuclear power plant such as a loss of coolant accident or when power is lost, usually the first response is to depressurize the … Continue reading

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