![Basic Knowledge on Radiation](https://www.r-info-miyagi.jp/site/wp-content/themes/miyagi/img/en_column-list-title2.png)
4.Characteristics of Radiation and Radioactivity
What are the characteristics of radiation and radioactivity?
What are the characteristics of radiation and radioactivity?
It's important to know about radiation and radioactivity in order to protect yourself. So Let's look at them together.
Characteristics of Radiation
Shielding
![Radioactive material](https://www.r-info-miyagi.jp/site/wp-content/themes/miyagi/img/column-monster.png)
![Radiation](https://www.r-info-miyagi.jp/site/wp-content/themes/miyagi/img/monster-beam-multiple.png)
Radioactive material
![壁](https://www.r-info-miyagi.jp/site/wp-content/themes/miyagi/img/column4_wall.png)
![博士](https://www.r-info-miyagi.jp/site/wp-content/themes/miyagi/img/column-4-doctor-1.png)
![Shielding](https://www.r-info-miyagi.jp/site/wp-content/themes/miyagi/img/en_column4-shield-sp.png)
Walls block radiation.
Concrete allows even less radiation through.
Separation (Distance)
The amount of radiation received
1
4
![Radioactive material](https://www.r-info-miyagi.jp/site/wp-content/themes/miyagi/img/column-monster.png)
![Radiation](https://www.r-info-miyagi.jp/site/wp-content/themes/miyagi/img/monster-beam-multiple.png)
Radioactive material
![距離が1倍離れている人](https://www.r-info-miyagi.jp/site/wp-content/themes/miyagi/img/column-4-doctor-2.png)
2 times farther away
![距離が2倍離れている人](https://www.r-info-miyagi.jp/site/wp-content/themes/miyagi/img/column-4-doctor-1.png)
![Shielding](https://www.r-info-miyagi.jp/site/wp-content/themes/miyagi/img/en_column4-distance-sp.png)
Does the radioactive material stay there forever?
The power of radioactive materials to emit radiation (radioactivity) has the property of decreasing over time.
The time it takes for that ability to halve is called the physical half-life.
Characteristics of Radioactivity
![half-life](https://www.r-info-miyagi.jp/site/wp-content/themes/miyagi/img/en_column4_hangenki.png)
Does radioactive material ingested through food stay in the body?
Don't worry. It will be discharged out of your body.
This is called the biological half-life.
Here's the point!
Radiation can be blocked and exposure can be reduced by moving away from radioactive materials.
The ability of a radioactive material to emit radiation decreases with time. (half-life).