Sources of Radiation Exposure
This is the most significant source of radiation exposure during a radiographic procedure.
What is the primary x-ray beam?
This radiation protection principle involves minimizing the duration of exposure.
What is time?
These wearable devices protect the body during x-ray procedures.
What are lead aprons?
ALARA is an acronym that stands for this.
What is As Low As Reasonably Achievable?
Besides scatter and leakage, what is the third primary source of radiation exposure in diagnostic radiology?
What is the primary x-ray beam?
This type of secondary radiation occurs when x-rays interact with matter and change direction
What is scatter radiation?
Doubling this factor significantly reduces radiation exposure.
What is distance?
The National Council on Radiation Protection and Measurements recommends this minimum lead equivalent for protective aprons.
What is 0.25 mm lead equivalent?
Name the three cardinal principles of radiation protection that directly supports the ALARA principle.
What is time, distance, or shielding?
Which of the cardinal principle of radiation protection is most effective in reducing exposure from a radioactive source that cannot be moved?
What is time (minimizing exposure duration)?
Leakage radiation is a type of this broader category of radiation exposure.
What is secondary radiation?
Lead aprons and gloves are examples of this type of radiation protection.
What is shielding?
Protective barriers should have this property to reduce radiation exposure.
What is attenuation?
ALARA emphasizes minimizing radiation exposure to whom?
What is radiation workers (or personnel), patients, and the general public?
What is the typical minimum lead equivalent for protective glasses used in diagnostic radiology?
What is 0.35 mm Pb?
Radioactive materials used in nuclear medicine procedures contribute to this source of radiation exposure.
What is the patient source?
If a technologist must remain in the room during an exposure, what is the most effective way to utilize the principles of time, distance, and shielding?
What is to stand behind a lead barrier (shielding) at the greatest possible distance from the primary beam, and only remain for the shortest necessary time?
Name two types of secondary protective barriers in a radiology room.
What are lead walls and lead glass windows?
How does the concept of "optimization" relate to ALARA?
What is optimization involves balancing the risk of radiation exposure with the benefit of the diagnostic information gained. It means striving for the best possible image quality with the lowest possible radiation dose.
Explain how using proper collimation contributes to the ALARA principle for both the patient and the technologist.
What is: Proper collimation restricts the size of the x-ray beam, reducing the amount of tissue irradiated in the patient, thus lowering their dose. It also reduces the production of scatter radiation, which in turn lowers the technologist's exposure.
Explain the difference between scatter radiation and leakage radiation.
* Scatter radiation is produced when the primary x-ray beam interacts with matter in or around the patient, causing the x-rays to change direction.
* Leakage radiation refers to x-rays that escape from the x-ray tube housing in directions other than the intended primary beam.
Explain how the inverse square law relates to radiation protection.
What is the inverse square law states that the intensity of radiation is inversely proportional to the square of the distance from the source. This means that as you double the distance from the radiation source, the radiation intensity decreases by a factor of four (and vice-versa). This highlights the importance of maximizing distance for radiation safety.
A technologist is performing a stationary radiographic examination. Describe the types of protective devices they should use, and minimum lead equivalent.
Lead Apron: Protects torso and reproductive organs. Attenuates scatter radiation. Minimum lead equivalent usually 0.25mm Pb, 0.5mm Pb recommended.
Lead Gloves: Protect hands. Attenuate scatter. Minimum lead equivalent usually 0.25mm Pb.
Thyroid Shield (if applicable): Protects the thyroid gland, especially during exams where the thyroid is in or near the primary beam or exposed to significant scatter. Attenuates scatter. Minimum lead equivalent usually 0.5mm Pb.
A technologist is preparing for a fluoroscopic procedure. Describe specific steps they can take to adhere to the ALARA principle during the exam, considering both their own protection and the patient's.
What is: For the technologist: wearing appropriate personal protective equipment (lead apron, gloves, thyroid shield if needed), maximizing distance from the x-ray tube and patient when possible, and utilizing shielding when available. For the patient: proper collimation of the x-ray beam to restrict the area exposed, using the lowest possible exposure factors (mAs, kVp) that still produce a diagnostic image, and shielding the patient's reproductive organs when they are not in the primary beam and it doesn't interfere with the diagnostic information needed.
A new radiology department is being designed. Discuss the key considerations for radiation protection that should be incorporated into the design of the x-ray room. You do not have to discuss the specific numbers, just what needs to be considered.
: What is: The design should prioritize minimizing radiation exposure to both staff and the public. Key considerations include: Shielding: Walls, floors, and ceilings of x-ray rooms must be constructed with sufficient shielding (typically lead or concrete) to attenuate primary and scatter radiation. The specific shielding requirements depend on the workload (number of exposures), kVp of the x-ray beam, and distance to adjacent areas. Calculations should be performed by a qualified expert (e.g., a medical physicist).