In the medical field of
radiation oncology, buildup refers to blocks of clear
plastic which are used by
physicists.
Buildup is heavy, similar to
plexiglass, but it is specially
formulated to have a
density comparable to that of ordinary
water. When a
radiation beam passes through water or buildup, it is
attenuated and
scattered. This same effect occurs when a radiation beam enters the
human body during
radiation therapy.
Because radiation is harmful to
living tissue, radiation oncologists must be able to simulate and quantify the scatter effects in order to ensure the safest possible conditions for the
patient while they are
irradiated. This process of verification is known as
radiation dosimetry, and it is vital for patient safety.
See: radiation oncology, radiation dosimetry