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Radiation Protection
Question | Answer |
---|---|
single, most important factor in helping patient dose to a minimum? | beam restriction/ collimation pg. 254, D.A. SAIA |
what are the three basic types of beam restrictors? | aperture diaphragms, cones, collimators pg. 254 D.A SAIA |
Controls quantity of x-rays with no effect on quality of x-rays | mAs pg. 257, D.A SAIA |
Controls quality of x-rays and also affects quantity of x-rays | kV pg. 257, D.A. SAIA |
in effort to keep radiation dose to a minimum you use the lowest____ and highest____ that produces desired radiographic results | lowest mAs and highest kV pg. 257, D.A SAIA |
NCRP guidline for equipment operating above 70kV for filtration requirement? | minimum, total plus added filtration, of 2.5mm Al equivalent. pg. 258 D.A SAIA |
At what range of collimated field should gonadal shielding be used? | within 5 cm of the collimated field pg. 259, D.A. SAIA |
How many types of AEC's currently exist? | Two, ionization chamber type and a phototimer type pg. 264, D.A. SAIA |
AEC type located between the patient and the IR? | ionization chamber pg. 264, D.A SAIA |
AEC type located beneath or behind the IR? | phototimer pg. 264, D.A SAIA |
When are grids appropriate to use? | for anatomy that measures more than 10cm pg. 265, D.A SAIA |
What is reproducibility? | the ability to consistently reproduce exposure output during repeated exposures at a particular setting. pg. 266. D.A SAIA |
What is linearity? | when a change in mA is doubled and the exposure time remains constant and the exposure is doubled. pg. 267, D.A SAIA |
variation in output intensity must not exceed what for reproducibility? | 5% pg. 267, D.A SAIA |
for linearity any variation in output intensity must not exceed _____? | 10% pg. 267, D.A SAIA |
x-ray tube housing must keep leakage radiation to what measurement? | less than 100mR/h when measured 1 m from the tube pg. 267, D.A SAIA |
PBL/ positive beam limitation device must correspond to what limitations for patient protection? | visible light within 4% of the SID pg. 267, D.A SAIA |
collimation devices must correspond to what limitations for patient protection? | visible light within 2% of SID pg. 267, D.A SAIA |
Limit for tabletop intensity of fluoroscopic beam | 10 R/min pg. 267, D.A SAIA |
x-ray tube housing leakage radiation must not exceed ___ | 100mR/h when measured 1 meter from the tube pg. 267, D.A SAIA |
tool for testing accuracy of x-ray timer for single-phase equipment? | spinning-top test tool pg. 267, D.A SAIA |
tool for testing accuracy of x-ray timer for three-phase equipment? | synchronous spinning tool or an oscilloscope pg. 267, D.A SAIA |
SSD must not be fewer than ____ for all radiographic procedures other than dental radiography. | 12 inches pg. 267, D.A SAIA |
What must the SSD be for fixed fluoroscopic equipment? | 15 inches pg. 267, D.A SAIA |
What must the SSD be for mobile fluoroscopic equipment? | 12 inches pg. 267, D.A SAIA |
What type of switch must exposure switches be? | "deadman's" switch pg. 267, D.A SAIA |
example of primary radiation barrier? | lead walls, doors of radiographic rooms. pg. 277, D.A SAIA |
requirements for primary radiation barrier? | walls 1/16th inch (1.5mm) lead thickness and 7ft height pg. 277, D.A SAIA |
what is secondary radiation? | leakage or scattered radiation. pg. 277, D.A SAIA |
what is the primary source of secondary radiation? | the patient pg. 277, D.A. SAIA |
example of secondary radiation barrier? | control booth, walls above 7ft in height, pg. 277, D.A SAIA |
required depth of lead for secondary barriers? | 1/32 inch lead pg. 277, D.A SAIA |
the three cardinal rules of radiation safety? | time, distance, shielding pg.276, D.A SAIA |
what is the minimum Pb equivalent requirement for lead aprons? | 0.25mm Pb equivalent pg.278, D.A SAIA |