１．What's radiation?

What radiation is／True character of radiation／Kinds of radiation
／Units of radiation／Radiation exsisting around us

You hear these word; radiation, radioactivity, radioactive material on the news. Are there different between these words?

“Radiation” is a particle or a radio wave to be emitted from “radioactive material”. This mechanism is likely to that a flashlight gives out light.
“Radioactivity” is ability to emit radiation, which is similar to that a flashlight has ability to emit light.
Of course, things emitted radiation doesn’t change into radioactivity material.

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Knowing true character of radiation is needed understanding mechanism of emitting radiation.

Radioactive material is an unstable atom in brief. It emits atomic nucleus or a part of electros when it becomes stable state by disintegrating. This is true character of radiation. Then , it changes a different element because the structure of the atom is changed.
This phenomenon is called radioactive disintegration.

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Name or properties of radiation are different by means of feature. For example, difference of the ability to penetrate things.

Alpha-ray　 Alpha-ray is bad at penetrating things. It can’t penetrate paper.

Beta-ray Beta-ray can pass through paper, but can’t do aluminum.

Gamma-ray Gamma-ray is good at penetrating things. But , it is stopped to penetrate by thick lead.

Neutron Neutron can pass through thick lead, but it is stopped to pass through by water or concrete.

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You hear these units; Bq, Sv on the news. Are there differences between these?

You hear these units; Bq, Sv on the news. Are there differences between these?
Becquerel (Bq) is unit of the strength of radioactivity how much radiation radioactive material emits per second.
Sievert (Sv) is unit of human effect of radiation. The quantity is extremely difference in case of external exposure and internal exposure.
Becquerel doesn’t easily convert into Sievert because these express something different.

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Where is radiation?

To tell the truth, everything around us emits radiation. Food also does. This is background radiation to be emitted by things including radioactive material.
A cloud chamber shows us track of radiation.

A radiation meter enables us to find background radiation.
To use radiation meter, hakarukun, let us know radiological dosages.
You can experience to measure radiological dosages in this site.
Radiological dosages of a drain or filter of an air conditioner are often high because it is easy for dust containing radioactive material to retain.

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