:Radiation definition es is the emission or transmission of energy in the fo material medium) This includes: CePoHEaeE radiation, such as radio waves, microwaves, infra visible light, (ultraviolet, x-rays, and gamma radiat a)Colest There is radiation coming from the depths of the univérse such as solar rays, cosmic rays, cosmic microwave background radiation and Hawking radiation. We also know the radiation emanating from the radioactivity of some materials. Some geological areas are also distinguished by their emission of radiation, which is called terréstriat radiation, and it arises from the presence of some radioactive -materials in the rocks of these lands JF = ~Types pia +Radiation is diff a Electromagnetic waves are made of photons. And X-rays, ultraviolet and infrared rays belong to it. Rays of short wavelength are called waves, including radio waves or radar -waves, and microwaves There is another type of radiation and it is called particle radiation, and there are many of them, such as alpha particles and beta particles - including the electron and including the positron - as some of them are called ions, and these are atoms that have lost one or more of their electrons, and there .are neutron rays )The examination shows that the radiation emanating © from the radioactivity of some materials is nothing but the radiation of particles such as: alpha particles and beta particles in time, what is a type of .electromagnetic waves such as gamma rays And when the energy of the rays is so high that it can © ionize the medium in which it passes, that is, it can separate electrons from its atoms or molecules, then this is called ionizing radiation. The ionizing radiation belongs to the electrons, protons and alpha particles, which are all particles with an electric charge. Also belong to ionizing rays, electromagnetic waves that carry high energy, such as x-rays and gamma rays @Electromagnetic radiation is characterized by © different wavelengths and frequencies, where this wide group of wavelengths is known as the electromagnetic spectrum. The electromagnetic spectrum is divided into seven regions according to the small wavelength or the large energy and frequency, which are in order from the smallest in .the energy to the highest Radio waves. © Microwaves © Infrared © Visible light © Ultraviolet © X-rays © Gamma rays ©non-ionizing non-thermal thermal induces low induces high | damages currents currents DN. 22? heating tanning medical tad Vv ove x-faysSources of Radiation -Natural Sources: -Man-Mode sources: Natural sources: Cosmic rays come to us from the space surrounding the globe, and when some of them reach the air surrounding the earth, they disperse and interact with the atoms of the air, including what comes to us from the sun due to the occurrence of whirlwinds and explosions on the surface of the sun, and the intensity of these rays is affected by the field and the magnetic center of the earth and by an increase from the surface of the sea, and we note that A person increases his exposure to these rays not only from his presence on the surface of the earth, but also by riding airplanes to high altitudes, for example:> wy wy 1 - Alpha waves :These waves are unable to penetrate the human body, and therefore their harmful effect is almost non-existent (a) . 2- Beta waves: These penetrate the surface layers of the body, and their range does not exceed a depth of 2 cm, and their harmful effect is minimal (B). 3- Gamma waves: These are mainly due to the harmful effect of radiation, as they penetrate deep into the body and affect all its organs, such as the bone marrow, the genitals, the nervous:Man-Mode sources Exposure of radiologists and their assistants - 1 .to diagnostic rays such as x-rays in hospitals Inhalation and ingestion of radioactive- 2 material dust by workers in the radioactive -materials fields -Exposure to atomic explosions- 3 The use of radioactive materials as weapons- 4 in warsRadiation is divided into two types 1- lonizing Radiation: lonizing radiation is a type of energy released by specific atoms and is transmitted in the form of electromagnetic waves (gamma rays or X-rays) or in the form of particles (neutrons, beta or alpha). This spontaneous dissociation of atoms is called radioactivity, and the excess energy released during this dissociation is considered to be a form of ionizing radiation.Non -lonizing Radiation: It is the radiation that has an electrical, magnetic, mechanical, thermal, or optical. origin ... etc. These radiations are considered less dangerous than the first type radiation, an example being the magnetic field and infrared radiation. It is worth noting that all materials are composed of atoms, almost all of the mass of the atom is concentrated in the nucleus, which consists of positively charged protons and neutral neutrons, and particles with a negative electric charge, called electrons, revolve around the nucleus..The figure shows an example of the structure of a helium atom. , And the atoms have an equal number of protons and electrons and their electrical charge is equal, and the total number of protons and neutrons forms the mass of the atom, which is called the mass number Electron - — charge (-) | Proton - positive charge(+) < Neutron-have no chargeExamples on vr ronznge Radiation Sources © > (low ererdy) Visible light © Microwaves © Radios © Video Display Terminals © Power lines © Radiofrequency Diathermy (Physical © )Therapy © Lasers © 15