Exam 6 Flashcards
If one is receiving 20mR/hr exposure at a distance of 3m from a source, at what distance would one receive 500mR/hr exposure?
a. 0.36cm
b. 0.36m
c. 60cm
d. 0.60cm
c. 60cm
If an area survey reveals an ambient radiation level of 7mR/hr, which of the following radioactive signs would be the best choice to display on the door leading to this area?
a. “Caution: Radioactive Materials”
b. “Caution: Radiation Area”
c. “Caution: High Radiation Area”
d. “Grave Danger: Very High Radiation Area”
b. “Caution: Radiation Area”
An ionization chamber is left in integral mode for 10min and records a total dose of 3mR. Which of the following area posting signs should be used on the door leading into this area?
a. “Caution: Radioactive Materials”
b. “Caution: Radiation Area”
c. “Caution: High Radiation Area”
d. “Grave Danger: Very High Radiation Area”
b. “Caution: Radiation Area”
Which of the following area posting signs would not normally be found in a hospital?
a. “Caution: Radioactive Materials”
b. “Caution: Radiation Area”
c. “Caution: High Radiation Area”
d. “Grave Danger: Very High Radiation Area”
d. “Grave Danger: Very High Radiation Area”
Which of the following type of survey instruments would be best to use to survey a spill for removable contamination in a hot lab area where radioisotopes are being stored?
a. G-M detector
b. personal pocket dosimeter
c. dose calibrator with a wipe test
d. well counter with a wipe test
d. well counter with a wipe test
Four HVLs reduce the amount of incident radiation exposure to what?
a. 12.5%
b. 6.25%
c. 3.125%
d. none of the above
b. 6.25%
Which of the following is not required to be included in the records of a radioactive package receipt check in progress?
a. name of patient
b. name of radioisotope
c. amount of activity
d. both external and internal wipe checks
a. name of patient
A package is reading 2mR/hr at a distance of 2m, what is the appropriate DOT label for the package?
a. DOT I
b. DOT II
c. DOT III
d. no labeling is required
b. DOT II
The purpose of the transport index is?
a. to list the final destination of the package
b. to indicate the highest activity of the contents at 1m from the surface
c. not to give emergency personnel information about the contents of the package in an accident
d. not to list the radioisotopes in the package
b. to indicate the highest activity of the contents at 1m from the surface
If a patient who is having a bone scan urinates on the floor next to the camera, what would be the best course of action to reduce radiation exposure?
a. let the radioactive urine decay to background
b. move the camera away from the spill
c. remove the spill with some absorbent material and cover any residual activity with a lead plate or lead apron
d. notify the referring physician of a medical event
c. remove the spill with some absorbent material and cover any residual activity with a lead plate or lead apron
Which DOT radioactive labeling is entirely white?
a. DOT I
b. DOT II
c. DOT III
d. DOT IV
a. DOT I
Which absorber would be the best to use to shield strontium 89?
a. cardboard
b. plexiglass
c. lead
d. no shielding is required
b. plexiglass
Which of the following indicates the amount of radioactive substance present in a sample or source?
a. activity
b. exposure
c. absorbed dose
d. dose equivalent
a. activity
If the exposure rate is 25mR/hr and the person being exposed is present for 25min, what is his/her total exposure?
a. 25mR
b. 12.5mR
c. 10.4mR
d. 5.2mR
c. 10.4mR
What is 120Sv in millirads (quality factor = 1)?
a. 8.3 x 10 to the -8 mrad
b. 120,000 mrad
c. 1.2 million mrad
d. 12 million mrad
d. 12 million mrad
An alpha particle is similar to what?
a. an electron
b. a proton
c. a helium atom minus its electrons
d. a helium atom minus its neutrons
c. a helium atom minus its electrons
A higher or lower sensitivity is affected by all of the following except?
a. thickness of camera crystal
b. collimator design
c. properly set pulse-height analyzer and window width
d. instrument deadtime
c. properly set pulse-height analyzer and window width
Geometric variation, on a dose calibrator, should be preformed?
a. at installation and after repair
b. at installation and yearly
c. quarterly
d. daily
a. at installation and after repair
Photomultiplier tube drift is associated with which of the following?
a. auto-voltage stabilization
b. auto-gain stabilization
c. energy correction
d. linearity correction
b. auto-gain stabilization
A paralyzable counting system will?
a. decrease in count rate after some peak in count rate is obtained
b. never plateau and never obtain a peak count
c. plateau with no decrease in count rate as activity increases, which is the peak count
d. not exhibit any count rate difference
a. decrease in count rate after some peak in count rate is obtained
Sources of intrinsic nonuniformity include all of the following except?
a. “mistuned” PMTs
b. regional variations in Z-pulse amplitude
c. linearity
d. spatial distortion
c. linearity
What is added to NaI crystals to allow them to scintillate at room temperature?
a. Tl
b. Xe
c. Ce
d. Ag
a. Tl
What is the maximum percentage difference that is acceptable for most regulatory agencies for all four dose calibrator QC checks?
a. plus or minus 5%
b. plus or minus 7%
c. plus or minus 10%
d. plus or minus 15%
c. plus or minus 10%
Extrinsic quality control on a camera means quality control is done?
a. with the collimator on
b. without the collimator on
c. inside the camera
d. outside the camera
a. with the collimator on