Deck 35: Health Physics

Question 1

Dose limits are based on a _____ dose-response relationship to radiation.

A) nonlinear, nonthreshold
B) linear, nonthreshold
C) linear, threshold
D) nonlinear, threshold

Answer 1

linear, nonthreshold

Question 2

Health physics is concerned with minimizing radiation dose to _____.

A) radiation physicists
B) radiation workers
C) the public
D) all of the above

Answer 2

all of the above

Question 3

The first radiation health physicists worked with _____.

A) the atom bomb
B) x-ray tubes
C) CT scanners
D) nuclear medicine

Answer 3

the atom bomb

Question 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

Question 5

If a technologist is receiving 2 mGyt/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

Question 6

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

Question 7

What is the NCRP?

A) National Council of Radiation Protection
B) National Council of Radiology Personnel
C) National Committee on Radiation Prevention
D) National Committee on Random Particles

Question 8

The dose limit for the general public is _____ the dose limit for occupational exposure.

A) 1/10
B) 1/5
C) 1/2
D) 3/4

Question 9

The NCRP publishes annual dose limits for _____ exposure.

A) public
B) occupational
C) prenatal
D) all of the above

Question 10

The concept of effective dose accounts for the _____.

A) different types of radiation and RBE
B) relative radiosensitivity of various tissues and organs
C) the person's distance from the source
D) both A and B

Question 11

The NCRP makes _____ regarding dose limits.

A) laws
B) recommendations
C) requirements
D) measurements

Question 12

What is the best approach to occupational radiation exposure?

A) Maintain the annual dose limits.
B) Follow the concept of ALARA.
C) Reduce your exposure to half the NCRP dose limits.
D) Wear protective apparel at all times.

Question 13

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

Question 14

The dose limits established by the NCRP are derived from _____.

A) government laws
B) newspaper articles
C) NCRP research
D) BEIR and NSC reports

Question 15

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

Question 16

If the HVL in a radiology department is 0.25 mm Pb,then how thick should a shield be to reduce the technologists' exposure to one fourth the incident scatter?

A) 0.125 mm Pb
B) 0.25 mm Pb
C) 0.5 mm Pb
D) 1.0 mm Pb

Question 17

A tenth-value layer is equal to _____ half-value layers.

A) 1.2
B) 3.3
C) 5.5
D) 10.0