Unit used from 1900-1930 to measure radiation expsure
Skin erythema dose
A measure of the amount of radiant energy that has been thrust into a portion of the pt's body surface
Dose area product (DAP)
Allowes units to be used interchangeably amoung all branches of science throughout the world
SI
Concept that helps explain the need for a quality, or modifying, factor
Linear energy transfer (LET)
Kinetic energy released in a unit mass of air
(kilogram)
Air kerma
SI unit of Equivalent dose (EqD)
Sv/mSv
Blood disorder resulting in abnormal overproduction of white blood cells after exposure to ionizing radiation
Leukemia
The product of D x Wr x Wt
Effective dose (EfD)
Blood disorder resulting from bone marrow failure after exposure to ionizing radiation
Aplastic anemia
Product of D x Wr
Equivalent dose (EqD)
Biologic damage to the body caused by exposure to ionizing radiation
Somatic damage
Raditation exposure received by radiation workers in the course of exercising their professional responsibilities
Occupational exposure
SI unit used to express absorbed dose (D)
Gy
Radiation quantity that is particularly useful dose monitor for occupational exposed personnel who are likely to receive possibly significant radiation exposure during the course of a year
TEDE
The amount of ionizing radiation that may strike an object such as the human body when in the vicinity of a radiation source
Exposure
The kinetic energy released in a unit mass of tissue
Tissue kerma
A dimesionless factor that was chosen for radiation protection purposes to account for differences in biologic impact amoung various types of ionizing radiation
Wr
A pear-shaped, partial vacuum discharge tube
Crookes tube
Fluorescent material that coated the paper used when x-rays were discovered
Barium platinocyanide
A composite, or weighted average, of the atomic #s of the many chemical elements comprising the tissue
Effective atomic number (Zeff)
Short-wavelength, higher-energy electromagnetic waves emitted by the nuclei of radioactive substances
Gamma radiation
The amount of energy per unit mass absorbed by an irradiated object
Absorbed dose (D)
SI unit of radiation exposure that is used for x-ray equipment calibration
C/kg
Expression 10^6 is symbolically expressed as
m
Radiation dose to which occupationally exposed persons could be continuously subjected w/o any apparent harmful acute effects
Tolerance dose
Early deterministic somatic affects of radiation include
-Nausea and fatigue
-Blood and intestinal disorders
-Redness of the skin and shedding of its outer layer
The total amount of radiant energy transferred by ionizing radiation to the body during a radiation exposure
Surface integral dose (Gy-m^2)
Fluoroscopic entrance dose rates can now be measured in
mGya/min
Measure of the probabilistic health effect on an individual as a result of an intake of radioactive material in the body
CEDE
Radiation quantity used to describe exposure of a population or group from low doses of different sources of ionizing radiation
Collective effective dose (ColEfD)
Have similar numeric value
Quality factor(Q) and Wr
Thomas Edison invented the
Fluoroscope
SI unit for Electrical current
ampere
X-rays, beta particles, and gamma rays have been given a numeric adjustment value of __
1
In therapeutic radiology, this unit is replacing the rad for recording of absorbed dose
cGy
First measure of exposure for ionizing radiation
Skin erythema dose
The unit of collective effective dose (ColEfD)
Person-sievert
Accounts for the risk to the entire organism brought on by irradiation of individual tissues and organs
tissue weighting factor (Wt)
SI radiation unit coulomb per kilogram measures
(C/kg or Roentgen)
Radiation exposure in the air only
Accounts for some biologic tissues' being more sensitive to radiation damage than other tissues
EqD
What does exposure deal with?
The air (not the pt)
Produce virtually the same biologic effect in body tissue for equal absorbed doses
X-rays, beta particles, and gamma rays
Atomic # for bone
13.8
The photon exposure that under standard conditions of pressure and temperature produces a total positive or negative ion charge of 2.58 x 10^-4 C/kg of dry air
Roentgen (R)
German physics professor who discovered x-ray and what year
Wilhelm Conrad Roentgen
1895
First American radiation fatality
Clarence Dally
Common blood disorders in early radiologists
Aplastic anemia
Leukemia
Unit was defined as the received quantity of radiation that causes diffuse redness over an area of skin after irradiation
Skin Erythema Dose
Appeared within minutes, hours, days, or weeks of the time of exposure
Early somatic effects
Appeared months or years after exposure
Late stochastic effects
Replaced the tolerance dose for radiation protection purposes; expressed in rem
Maximum permissible dose (MPD)
Takes into account the type of radiation and the sensitivity of the tissues exposed to radiation
EfD
5 radiation quantities
1. Exposure
2. Air kerma
3. Absorbed dose
4. EqD
5. EfD
(3,4, &5 only ones important to techs)
Essentially the sum total of air kerma over the exposed area of the pt's surface
Dose area product (DAP)
Affects the people in the x-ray room
Absorbed dose
Absorption increases as atomic # and mass density ______ and also as photon energy ______
Increases
Decreases
The traditional unit for absorbed dose is the
rad
1 Gy= __ rad
100
1Sv=__ rem
100
Nonthreshold, randomly occurring biologic effects of ionizing radiation such as cancer and genetic abnormalities; result from relatively low radiation exposure and takes a long time before demonstrated
Stochastic effects
Traditional unit for EqD
rem
Deals with the body and radiation
EfD