Monthly Archives: March 2011

What is an isotope?

It seems that there is a lot of confusion as to what isotopes, radioisotopes, nuclides, and radionuclides are.  First, we have to go back to chemistry class and remember the periodic table of elements, which lists all of the chemical … Continue reading

Posted in Basics

On worst case scenarios

On prediction of “worst case” scenarios The blog has received a great number of questions surrounding worst case scenarios. This is not surprising given that such scenarios, with varying degrees of scientific merit, have been advanced in the media. The … Continue reading

Posted in Incident History

Progress Update at Fukushima Daiichi – 3/17/11 (3:30 pm EST)

The high levels of radiation braved by workers at the scene in Fukushima Daiichi appear to have reduced after the expansion of the workforce and announcements of infrastructure improvements to come. In recent days emergency managers were faced with an … Continue reading

Posted in Fukushima

A Summary on Plutonium in Nuclear Fuel

Mixed Oxide (MOX) Fuel Uranium occurs naturally on earth. We mine it, refine it, and use it as fuel in nuclear reactors. All other elements that can sustain the nuclear fission chain reaction, including plutonium, do not occur naturally on … Continue reading

Posted in Basics | 1 Comment

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

Posted in Fukushima

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

Posted in Fukushima | 2 Comments

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

Posted in Basics

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

Posted in Fukushima