Certified Biomedical Equipment Technician (CBET) Practice Exam

Lead shielding is considered the most effective method of protection from ionizing radiation at the same thickness due to its high density and atomic number. The high atomic number of lead allows it to effectively absorb and attenuate gamma rays and x-rays, which are forms of ionizing radiation. When assessing materials for radiation protection, the ability of a material to attenuate radiation is linked to both its density and its atomic structure. While glass, aluminum, and concrete can offer some level of radiation shielding, they do not provide the same level of attenuation as lead when measured at equal thicknesses. Glass can attenuate certain types of radiation but is generally less effective than lead for high-energy photons. Aluminum's effectiveness is limited, particularly for high-energy gamma radiation, and concrete, though effective, requires significantly more thickness compared to lead to achieve a similar level of protection. In summary, the density and atomic number of lead make it the most effective choice for shielding against ionizing radiation, particularly in medical settings where equipment generates such emissions.