Radiation Protection and Safety Flashcards
6 cards from real CAMRT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Radiation Protection and Safety flashcards as text
According to the Canadian Nuclear Safety Commission (CNSC) Radiation Protection Regulations, what is the annual effective dose limit for a Nuclear Energy Worker (NEW)?
Answer: 50 mSv in any one year, and 100 mSv over five consecutive years
The CNSC sets the effective dose limits for a Nuclear Energy Worker at 50 mSv in any single year and 100 mSv over a five-year period. The 1 mSv limit is for the general public, the 20 mSv/year averaged limit is a common administrative control level but not the regulatory maximum, and the 4 mSv limit applies specifically to pregnant workers after declaration.
A medical radiation technologist is performing a mobile chest X-ray on a patient in the intensive care unit. To adhere to the ALARA principle, which of the following is the most effective action the technologist can take to minimize their own radiation exposure?
Answer: Increase the distance from the patient and primary beam to at least 2 meters during the exposure.
While all options are good radiation safety practices, the inverse square law states that radiation intensity decreases by the square of the distance from the source. Therefore, increasing distance is the most effective means for an operator to reduce their dose from scatter radiation during a mobile examination.
Which of the following best describes the primary objective of Health Canada's Safety Code 35?
Answer: To provide guidance for minimizing radiation exposure to patients, staff, and the public, while ensuring diagnostic image quality.
Health Canada's Safety Code 35 aims to provide guidance to achieve three main objectives: minimizing patient dose while maintaining diagnostic quality, ensuring adequate protection for equipment operators, and ensuring the protection of the public near X-ray facilities.
During a fluoroscopic procedure, where should the operator and other staff position themselves to minimize their exposure to scatter radiation?
Answer: On the side of the patient where the image receptor (image intensifier or flat-panel detector) is located.
The patient is the primary source of scatter radiation. The highest intensity of scatter radiation is on the side where the X-ray beam enters the patient (the tube side). The image receptor absorbs a significant portion of the primary beam, resulting in lower scatter on that side. Therefore, standing on the image receptor side significantly reduces occupational dose.
According to current Canadian guidelines and the position of the CAMRT, what is the recommended practice regarding gonadal shielding for most routine diagnostic X-ray procedures?
Answer: It is no longer recommended for routine use due to advancements in technology and the potential to obscure anatomy or interfere with automatic exposure control.
Major Canadian and international bodies, supported by the CAMRT, no longer recommend the routine use of patient gonadal shielding. Modern equipment uses significantly lower doses, and shields can obscure relevant anatomy, interfere with automatic exposure control (potentially increasing dose), and provide minimal benefit due to the low risk from internal scatter.
What is the annual effective dose limit for a member of the general public in Canada, as specified in the Radiation Protection Regulations?
Answer: 1 mSv
The Canadian Nuclear Safety Commission's (CNSC) Radiation Protection Regulations set the effective dose limit for the public at 1 mSv in one calendar year.