What is the SI unit of dose equivalent?

The SI unit of dose equivalent is the Sievert (Sv), which is a crucial measure in radiation protection. Dose equivalent accounts for the biological effect of different types of radiation, allowing for a more comprehensive understanding of radiation exposure's risks to human health. While the Gray (Gy) is the SI unit for absorbed dose, measuring the energy deposited by radiation per unit mass, it does not consider the varying impacts of different radiation types on biological tissues. This makes Sieverts essential for assessing potential health risks, particularly in medical settings and occupational exposure.

The other units listed serve different purposes: the Becquerel (Bq) measures radioactivity, denoting the number of decays per second, and C/kg is the unit of exposure in air, representing the charge produced by ionizing radiation in a specified mass of air. Therefore, the context in which each unit is applied underscores why Sievert is the appropriate choice for dose equivalent.