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Old 09-04-2011   #18
kowalskil
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Location: Fort Lee, New Jersey, USA
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Default Radiation levels in Japan

1) Those interested in recently (?) measured radiation levels (at different distances from the Fukushima reactors in Japan) should see:

#http://www.meti.go.jp/earthquake/nuc...nitor02_01.pdf #
(dose levels measured 1 meter above the ground)

#http://www.meti.go.jp/earthquake/nuc...nitor02_02.pdf
(dose levels measured 1 centimeter above the ground)

Note that the color code is explained near the lower left corner of each display. Radiation levels are expressed in micro-Sieverts per hour. [The 10 micro-sieverts, for example, is the same as 0.01 mSv, etc. And 10 micro-Sievert/hour is the same as 0.24 mSv/day, or 7.2 mSv/month.]

2) How significant are these levels? The effect of penetrating radiation on a person depends on the dose received. The common unit of dose is Sievert (Sv). Smaller doses are expressed in milliseverts (mSv) or microseveret.

A dose of 10 Sv will most likely results in death, within a day or two.
5 Sv would kill about 50% of exposed people.
2 Sv can also be fatal, especially without prompt treatment.

0.25 Sv = 250 mSv is the limit for emergency workers in life-saving operations.
0.10 Sv = 100 mSv dose is clearly linked to later cancer risks.
0.05 Sv = 50 mSv is the yearly limit for radiation workers.

0.004 Sv= 4 mSv typical yearly dose due to natural radiation (cosmic rays, etc).
0.003 Sv= 3 mSV typical dose from mammogram

Ludwik Kowalski (see Wikipedia)
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Ludwik Kowalski, author of a free ON-LINE book entitled “Diary of a Former Communist: Thoughts, Feelings, Reality.”

http://csam.montclair.edu/~kowalski/life/intro.html

It is a testimony based on a diary kept between 1946 and 2004 (in the USSR, Poland, France and the USA).

The more people know about proletarian dictatorship the less likely will we experience is.
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