ARRT Radiation Protection Principles 2

Question 1

Which quantity is used to express the effective dose received by a radiation worker and accounts for tissue sensitivity?

Accepted Answer

Effective dose (Sv)

Answer

Effective dose (Sv) weights equivalent doses by tissue weighting factors to reflect overall biological risk to the whole body.

Question 2

A radiographer doubles the distance from a fluoroscopy unit. By what factor does the radiation intensity change?

Accepted Answer

Decreases by one-fourth

Answer

According to the inverse square law, doubling the distance reduces intensity to 1/4 of the original value.

Question 3

Which type of radiation interaction is primarily responsible for photoelectric absorption in diagnostic radiology?

Accepted Answer

Photoelectric effect

Answer

The photoelectric effect dominates at lower kVp ranges used in diagnostic radiology, where the photon is completely absorbed by an inner-shell electron.

Question 4

What is the recommended annual occupational effective dose limit for radiation workers in the US according to NCRP?

Accepted Answer

50 mSv

Answer

NCRP Report No. 116 sets the annual occupational effective dose limit at 50 mSv (5 rem).

Question 5

Which material provides the most effective shielding against scatter radiation in a radiographic suite?

Accepted Answer

Concrete or lead

Answer

Lead and concrete are used for primary and secondary barriers because of their high atomic number and density, which attenuate X-rays effectively.

ARRT - American Registry of Radiologic Technologists Practice Test

ARRT - American Registry of Radiologic Technologists Practice Test

ARRT Radiation Protection Principles 2