ARRT Radiation Protection Principles 5

Question 1

During a portable chest X-ray, the technologist should stand at least how far from the patient if no protective barrier is available?

Accepted Answer

6 feet (2 meters)

Answer

Standing at least 6 feet (2 meters) from the patient and outside the primary beam significantly reduces scatter exposure during portable radiography.

Question 2

What type of radiation exposure effect describes cataracts developing after high-dose exposure to the eye?

Accepted Answer

Deterministic (nonstochastic) effect

Answer

Cataracts are a deterministic effect with a dose threshold; severity increases with dose above the threshold.

Question 3

Which of the following best defines the concept of 'workload' (W) in shielding calculations for a radiographic room?

Accepted Answer

Weekly total of mA-minutes at a reference kVp

Answer

Workload (W) is expressed in mA-min per week and represents the total amount of radiation produced, used in NCRP shielding design calculations.

Question 4

A technologist's monthly dosimeter reading shows 5 mSv. Which action is most appropriate?

Accepted Answer

Investigate work practices and potential sources of elevated exposure

Answer

5 mSv in one month is elevated (10% of the annual limit) and warrants investigation of work practices, even though it is not a regulatory violation.

Question 5

Which interaction between X-ray photons and matter is the primary source of occupational scatter radiation in diagnostic imaging?

Accepted Answer

Compton scatter

Answer

Compton scatter is the dominant interaction at diagnostic energies (above ~30 keV) and is the main source of scatter radiation reaching the technologist.

ARRT - American Registry of Radiologic Technologists Practice Test

ARRT - American Registry of Radiologic Technologists Practice Test

ARRT Radiation Protection Principles 5