Radiation Prepared by Timothy John D Matoy Radiation

Radiation Prepared by: Timothy John D. Matoy

Radiation is energy that comes from a source and travels through some material or through space. Energy emitted and transferred through space. The transfer of energy.

2 types of radiation Non-ionizing radiation Ionizing radiation

Ionizing Radiation Capable of removing an electron from an atom

2 Sources of Ionizing Radiation Natural Environmental Radiation Man-made Radiation

Natural Environmental Radiation Annual dose of approximately 300 millirem (mrem) (3 millisievert [m. Sv]) Cosmic rays, terrestrial radiation, internally deposited radionuclides

Man-made Radiation Approximately 60 mrem (0. 6 m. Sv) annually Medical imaging, nuclear power generation, research application, industrial sources, consumer items

Man-made Radiation Diagnostic x-rays constitute the largest man-made source of ionizing radiation (39 mrem/year) (0. 39 m. Sv/yr)

Two Types of Ionizing Radiation Particulate radiation Electromagnetic radiation

Particulate radiation Particle radiation is the radiation of energy by means of fast-moving subatomic particles.

Particulate radiation Alpha Particles Beta Particles

Alpha Particles Alpha particles are high energy, large subatomic structures of protons and neutrons. They can travel only a short distance and are stopped by a piece of paper or skin.

Beta Particles Beta particles are fast moving electrons. They are a fraction of the size of alpha particles, but can travel farther and are more penetrating.

Electromagnetic Radiation This kind of radiation is pure energy with no mass and is like vibrating or pulsating waves of electrical and magnetic energy. Electromagnetic waves are produced by a vibrating electric charge and as such, they consist of both an electric and a magnetic component.

Electromagnetic Radiation Gamma rays X-rays

Quantities and Units

Inverse Square Law The inverse square law can be applied to distances greater than seven times the longest dimension of the source

Inverse Square Law

Inverse Square Law

Sample Problem The intensity of light from a reading lamp is 100 millilumens (mlm), I 2, at a distance of 1 m, d 2. What is the intensity, I 1, of this light at 3 m?

Sample problem For a given technique, the x-ray intensity at 1 m is 450 m. R. What is the intensity at the edge of the control booth, at a distance of 3 m, if the useful beam is directed at the booth?

Practice problem For a given technique, the x-ray intensity at 2 m is 170 m. R. What is the intensity at a distance of 1 m?

A temporary chest radiographic imaging system is to be set up in a large hall. The technique used results in an exposure of 25 m. R at 180 cm. The area behind the chest stand in which the exposure intensity exceeds 1 m. R is to be cordoned off. How far from the xray tube will this area be extend?

A temporary chest radiographic imaging system is to be set up in a large hall. The technique used results in an exposure of 15 m. R at 230 cm. The area behind the chest stand in which the exposure intensity exceeds 1 m. R is to be cordoned off. How far from the xray tube will this area be extend?