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Biggest nuclear disasters

by Shazy | 2:17 PM in , , , , , , , |

Biggest nuclear disasters
Biggest nuclear accidents
Today marks the 25th anniversary of the nuclear accident at Chernobyl. In light of that, and the story continuing to unfold at Japan's Fukishima plant, we'll look at three of the worst nuclear plant disasters. First, to give some context, here's how the International Nuclear and Radiological Event Scale (INES) classifies each type of event:

Level 7 disaster
Major release of radioactive material; widespread health and environmental effects

Level 6 accident
Significant release; requires planned countermeasures

Level 5 accident
Limited release; several deaths from radiation

Level 4 accident
Minor release

Level 3 incident
Exposure in excess of 10 times the annual limit for workers; possible burns from exposure

Level 2 incident
Exposure of statutory annual limits

Level 1: Anomaly
Definition: • Overexposure of a member of the public in excess of statutory annual limits.
                • Minor problems with safety components with significant defence-in-depth remaining.
                • Low activity lost or stolen radioactive source, device or transport package.

Chernobyl
Date: April 26, 1986

Level: 7 on INES

Comparison: TheChernobyl plant accident released significantly more radiation into the atmosphere than the Hiroshima bombing during World War II. How does that compare with the Fukishima event?

What happened:

* Plant operators carrying out technical experiment switched off key safety systems
* Explosion blew off the reactor's 2,000-ton steel and concrete lid
* No secondary containment vessel
* Casualties
* Videos of the disaster

Aftermath:

* Reactor later entombed; since has developed cracks and is being replaced by new structure
* An 18-mile (30-km) exclusion zone remains in force
* You can visit the Chernobyl Museum in Kiev; tours are also offered inside the exclusion zone


Note: At the time of the accident, Chernobyl was located in the Soviet Union
Three Mile Island
Date: March 28, 1979

Level: 5 on INES

Comparison: Three Mile Island is said to have released a very low level of radiation. Some figures say the average exposure was equivalent to a common medical procedure.

What happened:

* Pump failed to circulate cooling water
* Efforts to ease pressure on reactor backfired when an open valve caused more coolant to pour out
* Rising temperatures caused hydrogen explosion in reactor building; 45 percent of the nuclear fuel rods melted
* After more than two hours, backup valve was shut, stopping leak; later reactor pump turned back on, temperature lowered
* Casualties – none
* Watch videos about the event


Aftermath:

* One of the plant's reactors was permanently shut down; the other is licensed to operate well into the future
Fukushima
Date: March 11, 2011

Level: Initially 4 on INES, upgraded to level 7 on April 12

Comparison: According to Japanese officials, the radiation levels near the plant rose to roughly twice those that constitute an emergency situation


What happened:

* 9.0-magnitude earthquake and following tsunami caused three of the six reactors at Fukushima plant to shut down
* Tsunami destroyed backup diesel generators, cut off pumps that circulate coolant around reactor cores
* Reactors overheated, causing partial meltdowns; explosions have damaged outer buildings
* Casualties

Aftermath:

* The latest on the disaster
* The evacuation zone has been recently extended
Source:Specials

Coulters Radiation Comments

by Shazy | 3:01 PM in , , , , , , , |

Coulters Radiation Comments
Coulter's radiation comments
Political pundit Ann Coulter claimed radiation is "good for you". Coulter is not the first to cause a stir since the tragedy in Japan. A Fox host said the earthquake may be "a message from God" and this comedian was fired for his jokes about the disaster.






Source: Specials

U.S. Radiation Risk

by Shazy | 2:36 PM in , , , , , , , , , , , , , , |

U.S. Radiation Risk

Radiation threats to the US

With reports that a radiation plume from the Fukushima Dai-ichi Nuclear Plant could reach Southern California, worried citizens have been hoarding certain pills , wondering if it's OK to go outside and otherwise fretting over an invisible, and somewhat unpredictable, threat.
But all that worrying might cause more harm than the radiation itself, experts say. Here are some answers to common concerns.

Possible levels of radiation

Q: How much radiation do scientists think will arrive here?
Answer
Details: No one knows yet -- but probably not a whole lot. It's unclear what's happening at the Japanese power plant -- and whatever radiation escapes has to travel thousands of miles to reach U.S. shores.  Over that distance, it will be greatly diluted, if it gets here at all.
In fact, the winds have been shifting, often pointing back westward to Japan rather than to the U.S., California officials said in a news conference Thursday. "We are not in Japan," said Dr. Jonathan Fielding, director of public health for Los Angeles County. "We are not within 10 miles of the reactor."

How much risk?

Q: How much risk will any radiation that does reach here pose?
Answer
Details: Gregory Jaczko, chairman of the Nuclear Regulatory Commission, an independent agency that regulates U.S. commercial nuclear power plants, said the basic science involved suggested that "there can't be any risk or harm to anyone here in the United States, or Hawaii, or any of the other (U.S.) territories."
Dr. Kei Iwamoto, of the faculty of the Division of Molecular and Cellular Oncology at the University of California, Los Angeles, said he believed the amount of radiation from Japan that a person in California might be exposed to will be very low -- perhaps around one microsievert.

Chernobyl & radiation

Q: Did radiation reach here from Chernobyl?
Answer
Details: "The radiation from the accident was negligible from a health standpoint. I know of no evidence that that accident caused any increase in cancer in this country," Iwamoto said.

Children & radiation

Q: What about kids? Are they more sensitive to radiation?
Answer
Details: "Kids are more vulnerable to radiation for a couple of reasons," said Dr. William Hendee, a radiation physicist with the Medical College of Wisconsin. "Their organs and tissues are growing and developing. Growing and developing cells are more susceptible to radiation. Kids also have a longer life span."
Q: So should they be kept away from school?
Answer: No. Radiation levels are not likely to get very high. There is no reason to keep children out of school.

Iodine tablets vs. iodized salt

Q: Should people take iodine tablets or eat iodized salt? It can't hurt, can it?
Answer
Details: The tablets can be risky for some people -- especially pregnant women. There is no reason to take iodine tablets at this point, said California officials.

Do masks help?

Q: Would wearing a mask help?
Answer
Details: "Masks would reduce a bit of the inhalation, but the amount of radioactive fallout is going to be so tiny," Hendee said. "For someone who is concerned or worried, if they felt better wearing a mask, they should wear a mask. I don't think it will reduce their risk, because the risk is already so low."

Authorities' contingency plans

Q: What contingency plans do local and national health authorities have?
Answer
Details: Although national health authorities defer to state governments, they will issue recommendations based on the severity of radiation levels, said Robert Taylor, a spokesman for the Nuclear Regulatory Commission. Possible recommendations include evacuating areas within 10 miles of a nuclear power plant; warning people to take shelter and close all doors and windows; and advising residents to consume potassium iodide tablets. "There's no need for U.S. citizens to take any protective measures at this time," he added.

Safety & radiation

Q: What can people do to be safer?
Answer
 
Details: Until more is known about the threat that radiation from the nuclear plant might pose in California and beyond, your best bet is to get yourself prepared -- for any expected emergency. Assemble your earthquake kit. Install gas shut-off valves, if your house doesn't already have them. "Rather than going out and buying potassium iodide, I would encourage everyone to go out and buy three to five days of food and water, so that when we have our earthquake, you can be self-sufficient," said Howard Backer, interim director of the California Department of Public Health.
 
Most of all, address the health threats that you can control. According to the federal government, almost 1.5 million Americans die each year of heart disease or tobacco-related diseases. The best bang for your buck might be throwing away cigarettes, exercising and improving your diet.
 
 
 
 
 
 
 
 
 
Source: Specials

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