CRA Radiation Physics & Safety Flashcards

Radiosensitivity of tissues is HIGHEST in which of the following?

Answer: Rapidly dividing cells such as bone marrow and gonads

Rapidly dividing cells, including bone marrow, gonads, and lymphoid tissue, are the most radiosensitive because radiation damage is most effective during cell division.

A radiology administrator is reviewing room shielding calculations. The term 'workload' in shielding design refers to:

Answer: The weekly total milliampere-minutes (mA·min) of X-ray use

Workload (W) in shielding calculations is expressed as the weekly total mA·min and represents the total radiation output used in that room.

Which document must a radiology facility maintain to demonstrate compliance with NRC radioactive material regulations?

Answer: Radioactive Material License

Facilities using radioactive materials must obtain and maintain a Radioactive Material License issued by the NRC or an Agreement State.

What is the recommended practice when a radiology staff member's monthly dosimetry reading exceeds the investigational level?

Answer: Document the reading and conduct an investigation to identify the cause

When readings exceed investigational levels, the radiation safety officer must document and investigate the cause to prevent future overexposure.

Which of the following BEST describes scatter radiation in a diagnostic imaging suite?

Answer: Secondary radiation produced when the primary beam interacts with the patient or objects

Scatter radiation is produced when the primary X-ray beam interacts with the patient or other objects, causing photons to change direction and spread throughout the room.

Pregnant radiology workers in the US are typically advised to limit fetal dose to no more than how much during the entire gestational period?

Answer: 0.5 rem (5 mSv)

NCRP Report No. 116 recommends limiting fetal dose to 0.5 rem (5 mSv) over the entire pregnancy once the pregnancy is declared.