radiation Flashcards
what is radiation?
energy in the form of electromagnetic wave or particulate matter that is travelling in the air
what is radioactivity?
unstable nucleus which emits or absorbs particles
what is ionizing radiation?
produced by unstable atoms that have an excess energy, excess mass or both which they emit in order to gain stability
what is ionizing radiation, in terms of electrons?
radiation has enough energy to eject one or more electron from the atoms or molecules exposed to the radiation
what are the natural sources of radiation?
1-cosmic rays from the sun
2- the earth
3- the human body
4- radon[ an element]
5- building materials
what are man-made sources of radiation?
1- consumer products
2- nuclear power
3- medical sources
4- fallout: nuclear explosions
what are the quantification of radiation?
1- quantifying radioactive decay
2- quantifying the exposure
3- quantifying the dose
what are the types of ionizing radiation?
1- gamma ray
2- beta particle
3- alpha particle
4- x-rays
5- neutrons
describe penetration ability from lowest to highest
alpha
beta
gamma and x-ray
describe ionization ability from the lowest to highest
gamma and x-ray
beta particle
alpha
what is an alpha particle
the nucleus of a helium, containing 2 protons and 2 neutrons
what is the charge on an alpha particle?
+2
what is alpha particle stopped by?
paper
where is alpha particle found?
1- soil
2- radon
3- radioactive materials
what are the types of beta particles?
electron and positron
what is the positron of beta particle?
subatomic particle with the same mass and numerically equal to electron but has a positive charge instead
where are the electrons emitted from to form beta particles?
the electrons are formed by the transformation of a neutron into a proton which remains in the nucleus and an electron which is transmitted at high speed
what is beta particle stopped by?
aluminum foil, and plastic
what is the hazourdnes of alpha particle?
it has internal hazards only if ingested as it cant travel far anyways
what is the hazourdness of a beta particle?
it has internal hazard and external hazard such as to the eye and skin
what is x-ray and gamma ray stopped by?
thick lead or concrete
what is x-ray radiation?
when an inner electron is removed, causing the remaining electrons to arrange themselves. the re-arranging release x-ray energy
what is gamma-ray?
waves of electromagnetic waves/energy emitted after the emission of a beta or alpha particle
what occurs during ionization at cellular level?
1-causes breakage in 1 or both DNA strands
2- causes formation of free radicals
what are the health effects of ionizing radiation?
1-generalization
2-acute somatic effects
3- delayed somatic effect
4- genetic effects
5- critical organs
describe generalization effect
ionization process destroys capacity of cell reproduction, divison and cell mutation
* the fatal does is 600k
describe acute somatic effect
ionization process causes immediate effects to person such as damage to bone marrow and intestinal wall which may lead to death
what does severity of acute somatic effect depend on?
the dose
describe delayed somatic effect
ionization process causes delayed effects to exposed person such as cancer, leukemia ,short lifespan and miscarriages
what does severtity of delayed somatic effect depend on?
other factors but not the dose
describe genetic effects
ionization process causes genetic effects which can be passed on to offspring and is irreversible and may be harmful
describe critical organ effect
ionization process causes nuclei of atoms of specific isotopes to concentrate in certain organs which are sensitive to radiation damage such as lymphocytes, bone marrow and intestinal wall
give an example for critical organ effect
isotopes of iodine concentrates in thyroid gland which is a critical organ for nuclides of iodine
define non-ionizing radiation
electromagnetic waves incapable of producing ions while passing through matter, due to their low energies
what are uses of radiation?
1-food sterilization
2- nuclear power:electricity
3- industrial use
4-medical use
outline path of incoming solar radiation
reflection, scattering and absorption all occur
what is albedo?
a measure of how well a surface reflects the suns rays
what are the effects of being exposed to radiation?
1- carcinogenicity: ability to cause cancer
2- cataracts: lens of eye develops cloudy patches
3- heating of the body
4- teratogenicity: ability to cause defect in developing fetus
what is the radio frequency range?
10 KHz to 300 GHz
what are 2 ways for radiation control?
1- basic control measure for external radiation
2- monitoring
describe basic control measure for external radiation
1-decrease time of exposure of workers by changing shifts
2-increase distance between workers and source
3-increases shielding between workers and source by placing a absorbing shield between them
describe monitoring
use of device which provide a record of accumulated exposure for an individual worker over extended period of time
what are devices used during monitoring?
1- pocket dosimeters
2- film badges
3-thermo luminescence detectors [TLD]
what are the elements of radiation protection program?
1- monitoring of exposure
2- task-specific procedures and control
3-emergency procedures
4-trainning and hazard communication
5-material handling
