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Understanding Radiation
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Understanding Radiation

We cannot eliminate radiation from our environment. We can, however, reduce our risks by controlling our exposure to it. Understanding radiation and radioactivity will help you make informed decisions about your exposure. 

What is radiation?

Radiation is energy that travels in the form of waves or particles. 

When we hear the word ' radiation,' we generally think of nuclear power plants, nuclear weapons, or radiation treatments for cancer. We would also be correct to add 'microwaves, radar, electrical power lines, cellular phones, and sunshine' to the list. There are many different types of radiation that have a range of energy forming an electromagnetic spectrum. However, when you see the word 'radiation' on this Website, we are referring to the types of radiation used in nuclear power, nuclear weapons, and medicine.  These types of radiation have enough energy to break chemical bonds, and are referred to as 'ionizing radiation.'  

more information  Ionizing and Non-Ionizing Radiation

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 What is radioactivity?

The radioactivity is the property of some atoms to spontaneously give off energy as particles or rays. The atoms that make up the radioactive materials are the source of radiation.

What is an atom?

To be able to understand radiation and radioactivity, you need to understand the language of atomic structure:

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Why some atoms are radioactive?

The balance of the forces in the nucleus of an atom determines whether a nucleus is stable or unstable, and is the key to answering these questions:

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How are people exposed to radiation?

When we hear the words ' radiation exposure,' we generally think of radiation from a source beaming out and striking the exterior of a body.  However, radioactive particles can also become lodged inside the body and expose internal organs as the radionuclides decay. As a result, health physicists consider not only the type of radiation emitted from a source but also the routes by which people are likely to come in contact with it. There are three main routes of exposure or exposure pathways:

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How does exposure to radioactive materials affect people?
Please see: Health Effects
How can we protect ourselves from harmful exposure to radiation?

Please see: Radiation Protection Basics

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