What is the intensity of scattered radiation at a distance of 1 meter from the patient compared to the useful beam at the patient's surface?

The intensity of scattered radiation at a distance of 1 meter from the patient compared to the useful beam at the patient's surface is understood to be significantly lower than that of the direct beam. When considering the figures presented, 0.1% reflects a realistic assessment of how much the scattered radiation diminishes over distance, especially when it’s measured far from the source of radiation.

As the distance increases from the patient, the scatter radiation diminishes due to the inverse square law, which indicates that radiation intensity decreases as the square of the distance from the source increases. Therefore, at 1 meter away, scattered radiation would be a mere fraction of the intensity of the useful beam at the surface of the patient, making 0.1% a plausible and accurate choice.

This understanding is crucial for personnel protection practices, as it highlights the importance of shielding and maintaining appropriate distances in medical imaging facilities to minimize exposure to scattered radiation.