GXMO Radiation Physics and Safety 5

Question 1

Which of the following best describes a deterministic (nonstochastic) radiation effect?

Accepted Answer

An effect with a threshold dose below which it does not occur, and severity increases with dose above the threshold

Answer

An effect with no threshold dose that increases in probability with dose

Answer

An effect that occurs randomly regardless of dose

Answer

An effect only seen in radiation workers, not patients

Question 2

What is the purpose of the x-ray tube housing?

Accepted Answer

To attenuate leakage radiation to acceptable levels

Answer

To generate x-rays more efficiently

Answer

To provide diagnostic filtration

Answer

To collimate the primary beam

Question 3

When is it appropriate for a radiographer to hold a patient during an x-ray exposure?

Accepted Answer

Only when no mechanical restraining device is available and a non-occupationally exposed person cannot assist

Answer

Whenever the patient is uncooperative

Answer

Routinely for pediatric patients

Answer

Whenever faster exposure times are needed

Question 4

What is the primary source of occupational radiation exposure for radiographers during fluoroscopic procedures?

Accepted Answer

Scatter radiation from the patient

Answer

Primary beam exiting the image intensifier

Answer

Leakage radiation from the tube housing

Answer

Characteristic radiation from the table

Question 5

What does collimation of the x-ray beam accomplish from a radiation protection standpoint?

Accepted Answer

Limits the irradiated field to only the area of clinical interest, reducing patient dose and scatter

Answer

Increases beam intensity to reduce exposure time

Answer

Increases photon energy to improve penetration

Answer

Removes characteristic radiation from the beam

Question 6

Which badge placement guideline applies when a radiographer wears a lead apron during fluoroscopy?

Accepted Answer

Wear the badge at collar level outside the apron to estimate effective dose

Answer

Wear the badge at waist level outside the apron

Answer

Wear the badge inside the apron at chest level

Answer

No badge is needed when wearing a lead apron

Question 7

What happens to x-ray beam quality (penetrating ability) when kVp is increased?

Accepted Answer

Beam quality increases because average photon energy increases

Answer

Beam quality decreases because photon energy decreases

Answer

Beam quality is unaffected; only quantity changes

Answer

Beam quality decreases because more low-energy photons are produced