Which formula should be used to convert from no grid to a grid?

The task of converting exposure techniques when moving from no grid to a grid involves understanding how the Grid Conversion Factor (GCF) affects the milliampere-seconds (mAs) used in the imaging process.

When there is no grid, a certain amount of radiation is required to achieve adequate image quality, represented by the old mAs. When a grid is introduced, it increases the overall radiation exposure necessary to maintain that same image quality due to its selective attenuation of scattered radiation.

To find the new mAs that should be utilized with the grid, the appropriate formula to use is to multiply the old mAs by the new GCF. This reflects the increased demand for exposure represented by the grid, effectively demonstrating the need for a compensation in mAs to maintain image quality. The formula captures the relationship between the mAs and the grid efficiency, ensuring that the final image is not underexposed.

The correct choice revealed here accurately reflects these foundational principles in radiographic technique adjustment, ensuring proper practices for medical radiation technologists.