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Rad. protection
ARRT exam review: radiation protection
Question | Answer |
---|---|
What is the monthly gestational dose limit for the embryo fetus of a pregnant radiographer? | 5mSv |
The interaction between ionizing radiation and the target molecule that is most likely that is most likely to occur is? | indirect effect |
Occupational radiation monitoring is required when it is possible that the individual might recieve more than? | 1/10 the annual dose limit |
Define radiolysis. | irraditaion of water molecules within the body resulting in breakdown. |
The exposure rate to a body 4ft from a source of radiation is 16 R/h. What distance from the source would be necessary to decrease the exposure to 6 R/h? | 7 ft. |
A thermoluminescent dosimetery system would use what type of crystal? | lithium fluoride |
Name three late radiation-induced late effects. | thyroid cancer, cataractogenesis, genetic mutations |
What contributes the most to occupational exposure? | compton scatter |
How will x-ray photon intensity be affected if the SID is doubled? | the intensity decreases 4 times. |
Medical and Dental radiation accounts for what percentage of the general public's exposure to human-made radiation? | 90% |
Immature cells are referred to as a)undifferentiated cells b)stem cells c) genetic cells | A and B |
The annual dose for occupationally exposed individuals is valid for what types of radiation? | beta, gamma, x-radiation |
How does filtratino affect the primary beam? | it increases the average energy of the primary beam. |
What unit of measre is used to express ionizing radiation dose to biologic material? | Rem (Sv) |
Biologic material is least sensitive to irraditaion under what conditions? | anoxic (unoxygenated) |
What does-response relationship represents radiation-induced leukemia and genetic effects? | linear, nonthreshold |
Patient dose increases as fluoroscopic FOV A)increases B) Decreases | B)decreases |
Diagnostic x-ray may be correctly described as | low energy, low LET |
How thick do primary radiation barriers have to be? | 1/16" lead |
For radiographic exams of the skull it is generally preferred that the skull be examined in what postition? (ex. AP, erect, PA, supine) | PA |
The annual occupational dose-equivalent limit (50 rem) to the thyroid, skin, and extremities is how many mSv? | 500 mSv |
What type of x-ray does aluminum filtration have its greatest effect on? | low-energy x-ray photons |
The law of Bergonie and Tribondeau states that cells are more radiosensitive if they are a) highly proliferative b)highly differentiated c)immature | A and C |
Why is the bucky slot cover in place? | to protect the fluoroscopist and technologist |
What term is used to describe the x-ray beam quality? | HVL |
Filters used in radiographic x-ray tubes generally are composed of? | aluminum |
The photoelectric effect is an interaction between an x-ray photon and what? | an inner-shell electron |