Potassium 40, the main source of radioactivity in our bodies, has a half-life of 1.42 billion years. Types of Radiation The term "radiation" is very broad, and includes such things as light and radio ...

All types of radiation become less intense as they travel further away from the radioactive material. This is because the particles or rays become more spread out. The thicker the substance ...

Radioactive materials are found naturally in ... 200,000 local residents were affected as many developed different types of ...