Radiation Health & SafetyQuestion 4 of 100
The operatory has no protective barrier or wall to stand behind during an exposure. What is the minimum distance and position the operator should use?
a.At least 3 feet away, standing directly behind the tubehead
b.At least 6 feet away, at a 90- to 135-degree angle to the primary beam
c.At least 6 feet away, standing in the path of the primary beam
d.At least 2 feet away, with the operator's back to the patient
Explanation
When no barrier is available the operator must stand at least 6 feet from the patient and at a 90- to 135-degree angle to the central ray, where scatter radiation is lowest. Three feet and two feet are both too close, and standing in the path of the primary beam exposes the operator to the most intense radiation. Distance and position work together with shielding as the three basic protective measures.
Law Reference: NCRP Report No. 145: Radiation Protection in DentistryPractice all 100 questions free — no signup required.
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