Rad 260: Safety Flashcards
(40 cards)
What is primary radiation?
Primary radiation is the initial radiation produced by the x-ray tube before interacting with any matter.
Define exit radiation.
X-rays that emerge from the patient and strike the image receptor
What is attenuation
Absorption and scatter of the x-ray beam as it passes through the patient
What is the photoelectric effect?
Absorption of x-ray photons in the atoms of the body
what does air kerma measure
Air kerma measures the kinetic energy released in air due to ionizing radiation.
Define the Gray unit.
Unit of absorbed dose, measured in joules per kilogram (J/kg); 1 Gy = 1 J/kg
What does the term ‘Graya’ refer to?
Unit of radiation absorbed in air
What is the primary responsibility of a radiographer?
Protecting the patient from unnecessary exposure
How much does natural background radiation contribute annually?
3.0 mSv annually
Natural background radiation comes from cosmic rays, terrestrial sources, and radon gas.
What is ionization?
Process of removing electrons from atoms due to ionizing radiation
Ionization is a fundamental effect of radiation on matter.
What are the two primary photon-tissue interactions significant in diagnostic x-ray procedures?
Photoelectric effect and Compton effect
These interactions are crucial for understanding how x-rays produce images.
What does the National Council on Radiation Protection and Measurements (NCRP) do?
Formulates and publishes scientifically researched recommendations on radiation protection and measurements in the United States
NCRP plays a key role in establishing safety standards for radiation exposure.
What is the linear-nonthreshold relationship in radiation exposure?
The degree of response to exposure is directly proportional to the amount of radiation received
This principle suggests that even small amounts of radiation can have a biological effect.
What is the linear-threshold relationship?
When the threshold dose is exceeded, the response is directly proportional to the dose received
This indicates that there is a certain level of exposure below which no biological effect is observed.
What is the total equivalent dose for a fetus during gestation?
5 mSv
This limit is set to minimize potential radiation exposure to the developing fetus.
What are the three main parts of a cell?
Cell membrane, Cytoplasm, Nucleus
Understanding cell structure is essential in radiobiology.
Define relative biologic effectiveness (RBE).
Ability to produce biological damage; varies with LET
RBE is an important factor in assessing the effects of different types of radiation.
What does the Law of Bergonié and Tribondeau state?
Cells are most sensitive to radiation when immature, undifferentiated, and rapidly dividing
This law is crucial in understanding the effects of radiation on different cell types.
What are the types of acute radiation syndrome?
Hematopoietic syndrome, GI syndrome, Central nervous system syndrome
Each syndrome has distinct symptoms and consequences based on the level of radiation exposure.
What are early tissue reactions (deterministic) in radiation exposure?
Erythema, Epilation, Decreased blood count, Acute radiation syndrome
These reactions occur after a certain threshold of radiation exposure.
What does OER stand for
Oxygen Enhancement Ratio
It indicates that if cells are more oxygenated, they are more susceptible to radiation damage.
Which blood cells are the most radiosensitive in the body?
Lymphocytes
Lymphocytes are crucial for the immune response and are particularly affected by radiation.
What are the two types of filtration in radiography?
Inherent and added
Inherent filtration is part of the tube, while added filtration refers to additional materials placed in the beam.
