The guiding principle of radiation safety is “ALARA”. ALARA stands for “as low as reasonably achievable”. ALARA means avoiding exposure to radiation that does not have a direct benefit to you, even if the dose is small.
What are the three basic principles of radiation exposure?
Three principles for radiation safety: time, distance, and shielding.
What are the 7 types of radiation?
The electromagnetic spectrum is generally divided into seven regions, in order of decreasing wavelength and increasing energy and frequency. The common designations are radio waves, microwaves, infrared (IR), visible light, ultraviolet (UV) light, X-rays and gamma-rays.
What are the types of radiation in physics?
There are four major types of radiation: alpha, beta, neutrons, and electromagnetic waves such as gamma rays.
What are the basic principles of interaction of radiation with matter?
Interaction with matter The radiation (such as β-particles, γ-rays, and x-rays) emitted by a radioisotope is isotropic; ie, it goes in all direction. As radiation travels through matter, it interacts with it, and energy is transferred from radiation to matter.
What are the two main aims of radiation protection?
Ionising radiation can trigger both deterministic and stochastic effects. The aim of radiation protection is to prevent reliably the deterministic effects of radiation and to reduce the risk of stochastic effects to a reasonably achievable level.
Why is the ALARA principle important?
The ALARA radiation safety principle is important since it can help prevent both unnecessary exposure and overexposure to ionizing radiation. There are three cardinal principles that anyone who works with radiation sources should follow to help keep radiation doses “as low as reasonably achievable”.
Why does distance affect radiation?
Distance: Just as the heat from a fire is less intense the further away you are, so the intensity and dose of radiation decreases dramatically as you increase your distance from the source. Shielding: Barriers of lead, concrete, or water provide protection from penetrating radiation such as gamma rays and neutrons.
What is inverse square law of radiation?
The inverse square law states that for a point source of waves that is capable of radiating omnidirectionally and with no obstructions in the vicinity, the intensity I decreases with the square of the distance, d, from the source.
What are the uses of radiation?
Today, to benefit humankind, radiation is used in medicine, academics, and industry, as well as for generating electricity. In addition, radiation has useful applications in such areas as agriculture, archaeology (carbon dating), space exploration, law enforcement, geology (including mining), and many others.
What are the two main types of radiation?
There are two kinds of radiation: non-ionizing radiation and ionizing radiation. Non-ionizing radiation has enough energy to move atoms in a molecule around or cause them to vibrate, but not enough to remove electrons from atoms. Examples of this kind of radiation are radio waves, visible light and microwaves.
How is radiation formed?
Ionizing radiation is produced by unstable atoms. Unstable atoms differ from stable atoms because unstable atoms have an excess of energy or mass or both. Radiation can also be produced by high-voltage devices (e.g., x-ray machines). Unstable atoms are said to be radioactive.
What is the unit of radiation?
The radiation dose absorbed by a person (that is, the amount of energy deposited in human tissue by radiation) is measured using the conventional unit rad or the SI unit gray (Gy).
What are the characteristics of radiation?
What is application of radiation in physics?
Radiation is used in industry in detectors that monitor and control the thickness of materials such as paper, plastic and aluminium. The thicker the material, the more radiation is absorbed and the less radiation reaches the detector. It then sends signals to the equipment that adjusts the thickness of the material.
What are the 5 interaction of matter?
Five main interactions can cause attenuation of photons: (1) coherent scattering, (2) photoelectric effect, (3) Compton scattering, (4) pair producion, and (5) photodisintegration.
What is design radiation?
2. Radiation in Interior Design. Rhythm can be achieved through radiation, whereby design elements are balanced and repeated around a centrepiece. By spreading movement in various directions from a central point, one can create interest from the point from which the elements radiate.
What is radioactivity PPT?
• It is the nucleus of an atom of an element which spontaneously disintegrates to emit α, β or γ-rays. • The rays emitted by radioactive element are called radioactive rays.
What can stop radiation?
Distance: Just as the heat from a fire reduces as you move further away, the dose of radiation decreases dramatically as you increase your distance from the source. Shielding: Barriers of lead, concrete, or water provide protection from penetrating gamma rays.
What are the methods of radiation protection?
- Lead aprons or vests. Wearing lead aprons can reduce a worker’s radiation dose.
- Lead thyroid collar.
- Lead gloves.
- Safety goggles.
Why is radiation safety important?
Radiation protection is to prevent the occurrence of harmful deterministic effects and to reduce the probability of occurrence of stochastic effects (e.g. cancer and hereditary effects).
What is the 10 day rule in radiology?
The “10 day rule” recommended that, in women of child-bearing potential, non-urgent x ray examinations that entailed pelvic irradiation should be restricted to the first 10 days of the menstrual cycle. Its rationale was to avoid irradiating a fetus before the mother realised that she was pregnant.
Who created ALARA principle?
In its 1990 Recommendations , ICRP introduced the current wording of the optimisation principle, known as the “ALARA” principle – As Low as Reasonably Achievable.
When was ALARA principle created?
To balance the risks and benefits of using radiation for diagnostics, the International Commission on Radiologic Protection (ICRP) has introduced the “As Low As Reasonably Achievable” (ALARA) principle in 1977 (ICRP, 1977; Hendee and Edwards, 1986).
What are the five sources of radiation?
- cosmic radiation.
- terrestrial radiation.