Radiation safety and dosimetry basics
Medical, bio and geophysics · Physics
Study notes
A technician needs to perform a task near a gamma source. The initial dose rate at 1 meter distance is 10 mSv/hour. The task takes 5 minutes. Calculate the total dose if the technician moves to 2 meters distance. Step 1: Determine the new dose rate at 2 meters using the Inverse Square Law. Formula: I2 = I1 * (d1/d2)^2 I1 = 10 mSv/h, d1 = 1 m, d2 = 2 m. I2 = 10 * (1/2)^2 = 10 * 0.25 = 2.5 mSv/hour. Step 2: Convert time to hours. Time = 5 minutes = 5/60 hours = 0.0833 hours. Step 3: Calculate total dose. Dose = Dose Rate * Time Dose = 2.5 mSv/hour * 0.0833 hours = 0.208 mSv. The technician receives a total dose of approximately 0.21 mSv.