Final answer:
Radiographic grids are recommended for body parts measuring greater than 10 cm in thickness to reduce scatter radiation and improve image quality.
Step-by-step explanation:
The question relates to the use of grids in radiographic imaging, specifically when imaging body parts to reduce scatter radiation and enhance image quality. In radiography, grids are recommended for body parts that measure greater than 10 cm in thickness. This is because thicker parts of the body increase the likelihood of scatter radiation, which can degrade the image quality on the radiograph. Radiographic grids are designed with lead strips to absorb the scatter radiation, therefore when imaging thicker body parts, the use of a grid is crucial to obtain a clear diagnostic image.