The unit of measurement for radiation exposure is known as the sievert (Sv). It quantifies the biological effects of ionizing radiation on human tissue. One sievert represents a significant amount of radiation exposure that can increase the risk of cancer and other health effects. Other units include the gray (Gy), which measures absorbed radiation dose but does not account for biological effects. Understanding sieverts is crucial in fields like radiology and nuclear safety to assess and manage radiation risks.