A 0.5-mm Pb equivalent apron attenuates what percentage of the scattered beam at 100 kV?

• A. 50%
• B. 65%
• C. 75%
• D. 85%

Answer: (C)

A 0.5-mm lead equivalent apron is designed to provide radiation protection by attenuating scattered radiation. At 100 kV, it effectively reduces much of the intensity of scattered beams. Lead equivalence is a standard measurement used to determine the protective capability of materials against radiation, and a thickness of 0.5 mm has been shown in studies to attenuate approximately 75% of the scattered photon beam.

This significant attenuation is crucial in radiation safety, particularly in radiographic procedures where personnel may be exposed to scattered radiation from the patient. The specific attenuation percentage can vary with different energies of the x-ray beam and beam quality; however, for 100 kV, the established figure typically used is around 75%. This substantial reduction emphasizes the importance of protective equipment in maintaining safety standards for radiologic technologists and their patients alike.