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RADT 465: RP
ARRT registry review Radiation Protection
Question | Answer |
---|---|
According to the NCRP, the monthly gestational dose-equivalent limit for embryo/fetus of a pregnant radiographer is? (PG 135) | 5 mSv |
A time of 1.5 minutes is required for a particular fluoroscopic examination, whose exposure rate is 275 mR/h. What is the approximate radiation exposure for the radiologic staff present in the fluoro room during the exam? (pg 135) | 6.87mR |
If the exposure rate to an individual standing 4.0m from a source of radiation is 10mR/h, what will be teh dose received after 20 minutes at a distance of 6m from the source? (pg 135) | 1.48 mR |
What type of cells have the greatest radiosensitivity in the adult human? (pg 136) | lymphocytes |
The interaction between ionizing radiation and the target molecule that is most likely to occur is the? (pg 136) | indirect effect |
What is the approx. entrance skin exposure for the average anteroposterior supine abdomen radiograph? (pg 136) | 300 mrad |
How will x-ray intensity be affected if the SID is doubled? (pg 136) | its intensity decreases four times |
What is established annual occupational dose-equivalent limit for the lens of the eye? (pg 136) | 150 mSv |
Occupational radiation monitoring is required when it is possible that the individual might receive more than? (pg 136) | one tenth the annual dose limit |
Irradiation of water molecules within the body and their resulting breakdown is termed? (pg 136) | radiolysis |
Which contributes more to occupation exposure? (pg 137) | Compton scatter |
The x-ray interaction with matter that is responsible for the majority of scattered radiation reaching the image receptor is? (pg 137) | Compton scatter |
With mA increased to maintain output intensity, how is the ESE affected as the SSD is increased? (pg 137) | The ESE increases |
Each time an x-ray beam scatters, its intensity at 1m from the scattering object is what fraction of its original intensity? (pg 137) | 1/1,000 |
According to the NCRP, the annual occupational whole-body dose-equivalent limit is? (pg 137) | 50 mSv |
A thermoluminescent dosimetry system would use which of the following crystals? (pg 137) | Lithium flouride |
In radiation protection, the product of absorbed dose and the correct modifying factor is used to determine? (pg 138) | rem (Sv) |
Medical and dental radiation accounts for what percentage of the general public's exposure to human-made radiation? (pg 138) | 90% |
What is the minimum lead requirement for lead aprons, according to the NCRP? (pg 139) | 0.05 mm Pb |
An optically stimulated luminescence dosimeter contains which? (pg 139) | Aluminum oxide |
What is the term used to describe x-ray photon interaction with matter and the transference of part of the photon's energy to matter? (pg 139) | Scattering |
What is the approx. ESE for the average upright PA chest radiograph using 115 KVP and a grid? (pg 139) | 20 mrad |
To be in compliance with radiation safety standards, the fluoroscopy exposure switch much? (pg 139) | be the "dead man" type |
Primary radiation barriers must be at least how high? (pg 139) | 7 ft |
The annual dose limit for occupationally exposed individuals is valid for? (pg 139) | beta, x-and gamma radiations |
Patient dose increases as fluoroscopic? (pg 140) | FOV decreases |
What unit of measure is used to express ionizing radiation dose to biologic material? (pg 140) | Rem (Sv) |
The skin response to radiation exposure that appears as hair loss is known as? (pg 140) | epilation |
Biologic material is least sensitive to irradiation under which conditions? (pg 140) | Anoxic |
The reduction in the intensity of an x-ray beam as it passes through material is termed? (pg 140) | attenuation |
What type of dose-response relationship represents radiation-induced leukemia and genetic effects? (pg 141) | linear, nonthreshold |
A dose of 25 rad to the fetus during the seventh or eight week of pregnancy is likely to cause which? (pg 141) | neurologic anomalies |
Late effects of radiation, whose incidence is dose related and for which there is no threshold dose,are referred to as? (pg 141) | stochastic |
The largest amount of diagnostic x-ray absorption is most likely to occur in which tissues? (pg 141) | bone |
According to NCRP regulations, leakage radiation from the x-ray tube must not exceed? (pg 141) | 100 mR/h |
Which most effectively minimizes radiation exposure to the patient? (pg 141) | high-speed intensifying screens |