RADIATION PROTECTION

Radiation Protection

Radiation Protection

What is Radiation?

In physics, radiation is a process in which energetic particles or energy or waves travel through a medium or space. There are two distinct types of radiation; ionizing and non-ionizing. The word radiation is commonly used in reference to ionizing radiation only (i.e., having sufficient energy to ionize an atom), but it may also refer to non-ionizing radiation (for example, radio waves or visible light). The energy radiates (i.e., travels outward in straight lines in all directions) from its source. This geometry naturally leads to a system of measurements and physical units that are equally applicable to all types of radiation. Both ionizing and non-ionizing radiation can be harmful to organisms and can result in changes to the natural environment (Robinson, 2010, 1-3).

Radiation (electromagnetic radiation) is the result of a charged particle that is moving. The charged particle disturbs the space around it in a similar way that a pebble dropped into a calm pond of water creates waves on the surface of the water. It is a method of energy transfer. For electromagnetic energy, (or waves) the charged particle sends out a wave, or a disturbance, in space. These waves travel in 3 dimensions at the speed of light. This is electromagnetic radiation. The radiation depends on how much energy the charged particle has when it is moving, generally the faster it moves the greater the electromagnetic energy (Rapp, 2008, 42-51).

Radiation with sufficiently high energy can ionize atoms. Most often, this occurs when an electron is stripped (or 'knocked out') from an electron shell, which leaves the atom with a net positive charge. Because cells and more importantly the DNA can be damaged, this ionization can result in an increased chance of cancer. A single cell is made of trillions of atoms. The probability of ionizing radiation causing cancer is dependent upon the dose rate of radiation and the sensitivity of the organism being irradiated (Forster, et al, 2007, 105-121). Alpha particles, beta particles, gamma rays, X-ray radiation, and neutrons may all be accelerated to an energy high enough to ionize atoms.

Neutrons are categorized according to their speed. High-energy (high-speed) neutrons have the ability to ionize atoms and are able to penetrate materials deeply. Neutrons are the only ionizing radiation that can make other objects, or material, radioactive. This process, called neutron activation, is the primary method used to produce radioactive sources for use in medical, academic, and industrial applications.

Why we concern on radiation?

A high dose of radiation can kill in hours. In small doses, it can slowly get into cancer. The fact is that we are constantly being bombarded by natural or artificial radiation, coming from the sky, soil, food we eat or the air we breathe. Every second, more than 100 cosmic rays, pass through our bodies. While many radioactive atoms are inhaling air that eventually disintegrate into our lungs. A few thousand of potassium atoms and two or three atoms of uranium are in the foods we eat and drank ...