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Exhibit 4
How to Protect Ourselves from Ionizing Radiation?

How to Protect Ourselves from Ionizing Radiation?   
Ionizing radiation includes alpha particles, beta particles, X-rays and gamma rays as well as neutrons.

  1. Alpha particles : helium nuclei (2 protons and 2 neutrons) carrying positive charges. Because of their larger mass, they have very little penetration power.
  2. Beta particles : high speed electrons. They are more penetrating than alpha particles.
  3. X-rays and gamma rays : they can pass right through the body.
  4. Neutrons : uncharged particles and most penetrating.

We use different shields to protect ourselves from radiation.  For radiation with low penetrating power such as alpha particles, they can easily be stopped by a sheet of paper.  For high penetrating radiation, thicker shields made up of dense materials, such as lead or paraffin, are required.

What is Non-ionizing Radiation?Exhibit 3
Exhibit 5 What is Half-Life?
Last revision date: <20 Dec 2012>