This is a unit of measurement of the ionization produced in air by photons.
What is the roentgen
100
This acronym is a radiation safety principle and regulatory requirement for minimizing radiation doses and releases of radioactive materials by employing all reasonable methods.
What is ALARA- As Low As Reasonably Achievable
100
This is located on the carousel, and shapes the x-ray beam in its cross-sectional dimension. It is a conical metal absorber that absorbs more photons from the central axis and fewer from the periphery of the beam.
What is a flattening filter
100
These are safety switches that block or terminate radiation production if certain requirements are not met, such as the closing of doors, placement of proper beam modifiers, and machine-operation requirements.
What are interlocks
200
This photon interaction causes an orbital electron to be ejected, and a characteristic x-ray to be given off when an outer shell electron fills the vacancy.
What is the photoelectric effect
200
This is the energy absorbed per unit mass of the irradiated material. It is a measure of the biologically significant effects produced by ionizing radiation.
What is absorbed dose
200
This is the annual effective dose equivalent limit for radiation workers.
What is 50 mSv (5 rem) per year
200
This essential part of the linear accelerator is responsible for producing electrons and injecting them into the accelerator structure.
What is the electron gun
200
These buttons are located at several points within the treatment room and on the machine itself that will remove all power to the unit when pressed.
What are emergency off buttons
300
In this photon interaction, the photon interacts with an atomic electron as though it were a "free" electron. The electron receives some energy from the photon and is emitted at an angle. The photon is scattered at an angle.
What is the Compton effect
300
This is a gene that regulates the development and growth of cancerous tissues.
What is an oncogene
300
This is the annual effective dose equivalent limit for the general public, who are infrequently exposed to radiation.
What is 5 mSv (.5 rem) per year
300
This special type of electron tube is used to provide microwave power to accelerate electrons. It functions as a high-power oscillator and typically operates at 2 MW peak power output to power low-energy linacs (<6 MV).
What is a magnetron
300
If temperature decreases or pressure increases, this result will happen to exposure measurements for an unsealed ion chamber.
What is an increased ion chamber reading
400
This effect is seen for heavy charged particles, which involves the peaking of dose near the end of the particle range, before dropping to an almost zero value.
What is Bragg peak
400
This type of gas-filled detector consists of two electrodes within a gas-filled chamber, an applied voltage across the electrodes, and electronics and a meter to amplify and measure the electrical signal.
What is an ionization chamber
400
This is a limited-access area in which the occupational exposure of personnel to radiation or to radioactive
material is under the supervision of a radiation protection supervisor. The dose equivalent limit is 0.1 rem/week (5 rem/year).
What is a controlled area
400
This hollow, tube-like structure within the linear accelerator is used to accelerate injected electrons to near the speed of light prior to striking a target to produce photons.
What is an accelerator waveguide
400
This is the frequency that light/radiation field coincidence and gantry/collimator angle indicators should be checked, based on the American Association of Physicists in Medicine (AAPM).
What is monthly
500
This is a mathematical relationship that describes the change in beam intensity as the distance from the source changes, where intensity is inversely proportional to the distance squared.
What is the inverse square law
500
This is a device for measuring dose, which when irradiated, will subsequently give off light when heated. The amount of light emitted is proportional to the dose delivered to the crystal.
What is a thermoluminescent dosimeter (TLD)
500
This is a barrier sufficient to attenuate the useful beam to the required degree.
What is a primary barrier
500
This special type of electron tube is used to amplify microwaves; it does not generate microwaves. It needs to be driven by a low-power microwave oscillator and is generally used for high-energy linacs (>6 MV).
What is a klystron
500
This is the frequency that the door interlock, localizing lasers, and optical distance indicator (ODI) should be checked, based on the American Association of Physicists in Medicine (AAPM).