California Registered Dental Assistant (RDA) Written Practice Exam

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The California Radiological Safety Code requires the patient protection apron to contain at least what thickness of lead?

  1. .50 mm

  2. .25 mm

  3. .75 mm

  4. 1 mm

The correct answer is: .25 mm

The California Radiological Safety Code requires the patient protection apron to contain at least a thickness of .25 mm of lead in order to adequately protect the patient from radiation exposure. Option A of .50 mm is too thick and may be unnecessarily heavy and uncomfortable for the patient to wear. Option C of .75 mm is also thicker than necessary, and the extra weight may cause additional strain on the patient. Option D of 1 mm may also provide enough protection, but it is not required by the safety code and may be more expensive and less comfortable for patients. Therefore, B is the most appropriate and accurate answer.