Chapter 37 Health Physics Bushong: Radiologic Science for Technologists
MULTIPLE CHOICE
1. Health physics is concerned with minimizing radiation dose to . a.
radiation physicists
b. radiation workers
c. the public
d. All of the options
ANS: D
Health physics is concerned with providing occupational radiation protection and
minimizing radiation dose to the public.
2. The first radiation health physicists worked with .
a. the atom bomb
b. x-ray tubes
c. CT scanners
d. nuclear medicine
ANS: A
The first radiation health physicists worked with the atom bomb.
3. The three cardinal principals of radiation protection involve .
a. dose, shielding, and exposure
b. exposure, shielding, and ALARA
c. time, distance, and shielding
d. ALARA, time, and distance
, ANS: C
The three cardinal principals of radiation protection involve time, distance, and shielding.
4. Exposure is measured by multiplying
by .
a. shielding thickness; exposure time
b. exposure rate; exposure time
c. exposure rate; shielding thickness
d. exposure time; distance
ANS: B
Exposure is measured by multiplying exposure rate by exposure time.
5. If a technologist is exposed to 4 mGyt/hr for 45 minutes during a fluoroscopy exam,
what will be her total exposure? a. 1 mGyt
b. 2 mGyt
c. 3 mGyt
d. 4 mGyt
ANS: C
Exposure = exposure rate exposure time; therefore, her total exposure is 4 mGy t/hr
3/4 hr, which equals 3 mGyt.
6. When using the inverse square law during fluoroscopy, the patient should be considered
a(n) source of radiation.
, a. area
b. linear
c. round
d. point
ANS: D
When using the inverse square law during fluoroscopy, the patient should be
considered a point source of radiation.
7. If a technologist is receiving 2 mGy t/hr standing 1 foot from the patient during
fluoroscopy, what is his rate of exposure when he steps back to a distance of 2 feet from
the patient? a. 0.50 mGyt/hr
b. 0.74 mGyt/hr
c. 1 mGyt/hr
d. 1.75 mGyt/hr
ANS: A
Using the inverse square law, doubling the distance will reduce the dose rate to one fourth
of what it was. His exposure rate at a distance of 2 feet will be 50 mR/hr.
8. A tenth-value layer is equal to half-value layers.
a. 1.2
b. 3.3
c. 5.5
d. 10.0
ANS: B
MULTIPLE CHOICE
1. Health physics is concerned with minimizing radiation dose to . a.
radiation physicists
b. radiation workers
c. the public
d. All of the options
ANS: D
Health physics is concerned with providing occupational radiation protection and
minimizing radiation dose to the public.
2. The first radiation health physicists worked with .
a. the atom bomb
b. x-ray tubes
c. CT scanners
d. nuclear medicine
ANS: A
The first radiation health physicists worked with the atom bomb.
3. The three cardinal principals of radiation protection involve .
a. dose, shielding, and exposure
b. exposure, shielding, and ALARA
c. time, distance, and shielding
d. ALARA, time, and distance
, ANS: C
The three cardinal principals of radiation protection involve time, distance, and shielding.
4. Exposure is measured by multiplying
by .
a. shielding thickness; exposure time
b. exposure rate; exposure time
c. exposure rate; shielding thickness
d. exposure time; distance
ANS: B
Exposure is measured by multiplying exposure rate by exposure time.
5. If a technologist is exposed to 4 mGyt/hr for 45 minutes during a fluoroscopy exam,
what will be her total exposure? a. 1 mGyt
b. 2 mGyt
c. 3 mGyt
d. 4 mGyt
ANS: C
Exposure = exposure rate exposure time; therefore, her total exposure is 4 mGy t/hr
3/4 hr, which equals 3 mGyt.
6. When using the inverse square law during fluoroscopy, the patient should be considered
a(n) source of radiation.
, a. area
b. linear
c. round
d. point
ANS: D
When using the inverse square law during fluoroscopy, the patient should be
considered a point source of radiation.
7. If a technologist is receiving 2 mGy t/hr standing 1 foot from the patient during
fluoroscopy, what is his rate of exposure when he steps back to a distance of 2 feet from
the patient? a. 0.50 mGyt/hr
b. 0.74 mGyt/hr
c. 1 mGyt/hr
d. 1.75 mGyt/hr
ANS: A
Using the inverse square law, doubling the distance will reduce the dose rate to one fourth
of what it was. His exposure rate at a distance of 2 feet will be 50 mR/hr.
8. A tenth-value layer is equal to half-value layers.
a. 1.2
b. 3.3
c. 5.5
d. 10.0
ANS: B
