What is the dose rate when recalculating for a distance of 200 feet from the original source used in a previous calculation?

To understand the dose rate at a distance of 200 feet from a radiation source, one must apply the principles of radiation physics, particularly the inverse square law. This law indicates that the intensity of radiation (or dose rate) decreases with the square of the distance from the source.

When recalibrating the dose rate for a new distance further away from the original source, you start with the known dose rate at the original distance and adjust it based on the change in distance.

If the original calculations provided a certain dose rate at a given distance, moving to 200 feet would typically result in a lower dose rate, reflecting the increased distance which leads to a reduced intensity due to radiation dispersal in the environment.

In this case, if the calculated dose rate at 200 feet is 12.5 mR/hr, this indicates a decrease well accounted for by the squared relationship dictated by the inverse square law. The value of 12.5 mR/hr suggests that previous calculations for dose rates at varying distances were accurately adjusted to account for the increase in distance.

By applying these principles, the dose rate of 12.5 mR/hr represents the outcome of proper recalculation for the increased distance of 200 feet from the radiation