Ch2 Flashcards
Two largest source of artificial radiation
Radiography and Fluoroscopy
Computed Tomography (CT) procedures
Medical radiation annual EFD averages about
2.3 msv
- Consumer products containing radioactive material
> Air travel
> Nuclear fuel for generation of power
> Atmospheric fallout from nuclear weapons testing
> Nuclear power plant accidents)
> Nuclear power plant
Human made artificial radiation
Terrestrial radiation
internal radiation and
cosmic radiation
are all examples of
Natural radiation
(e.g., radon, thoron) 2.5 mSv (Radon
accounts for nearly all of the natural background radiation, a decay product of radium)
Terrestrial radiation
from radioactive atoms (also called
radionuclides
0.3 mSv
Internal radiation
(solar and galactic) 0.3 mSv
The global population is mostly shielded from this due to the
atmosphere and the earths magnetic field.
Cosmic radiation
(solar and galactic) 0.3 mSv
The global population is mostly shielded from this due to the
atmosphere and the earths magnetic field.
Cosmic radiation
If ionizing radiation from natural resources grows larger because of accidental or deliberate human actions such as mining radioactive elements,
Enhance natural sources
Approximately 50 to 55% of total annual radiation
Natural radiation
3.1 msv anually
 Natural radiation
Approximately 45 to 50% Of radiation annually
Human made artificial radiation
Annual does from human artificial made radiation is approximately
0.1 msv
Annual total dose for all medical human made a natural radiation is approximate
5.5 msv
Ionizing radiation primary cause
Biologic damages
Produced by ionizing radiation while penetrating body tissue primarily by ejecting electrons from atoms composed tissues
Biologic damage
Results of destructive radiation interaction at atomic level 3 types
Molecule cellular organic
the dose for all ( overall) types of ionizing radiation (e.g., alpha, beta,
gamma, ×-ray)
Measured in millisievert msv
Effective dose
8000 times lighter than alpha particles and haveonly one unit of electric charge (-1
- penetrate matter yo a greater depth
Weaker particle
Beta ray
Type of ionizing radiation that was absorbed
Measured in MSV
Equivalent dose EQD
Amount of kinetic energy per unit Mass that has been absorbed in a material 
Measured in milligray MGY
Absorbed dose
Same number of protons different number of neutrons
Isotope
Combinations of Z protons And some neutron leads to unstable nucleus
Radioisotope
Beta particles produced in a radiation oncology treatment machine
Used to treat breast tumors and skin lesions 
Linear accelerator
Less than 2MEV
Beta particles
Emitted from nuclei of very heavy elements such as uranium and plutonium during the process of
radioactive decay
-Have a large mass (approximately four times the mass of a hydrogen atom) and a positive charge twice that of an electron
Alpha particles 
alpha particles, beta particles, neutrons, and protons All these are
- possess sufficient kinetic energy to be capable of causing ionization by direct atomic collision.
• No ionization occurs when the particles are at rest.
Subatomic particle
Amount of energy transferred to electrons by ionizing radiation
Radiation dose
(x-rays, gamma rays, and high-
energy ultraviolet radiation [energy higher than 10 eV can transfer sufficient energy to some orbital electrons to remove ther from the atoms to which they were
attached (the process of ionization, the foundation of
the interaction of x-rays with human tissue),
ionizing radiation
(ultraviolet radiation [energy
less than 10 eVl, visible light, infrared rays,microwaves, and radio waves) does not have sufficient
kinetic energy to eject electrons from atoms.
Non-ionizing radiation
