Deck 35: Health Physics

Question 1

The first radiation health physicists worked with ___________________.

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

Answer 1

the atom bomb

Question 2

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.

Answer 2

Follow the concept of ALARA.

Question 3

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

Answer 3

1/10

Question 4

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 5

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 6

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 7

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

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

Question 8

The NCRP makes _________________ regarding dose limits.

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

Question 9

The NCRP publishes annual dose limits for _____________ exposure.

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

Question 10

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 11

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 12

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 13

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 14

Health physics is concerned with minimizing radiation dose to ________________.

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

Question 15

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 16

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 17

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

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