What two units are used to measure biological effect and dose equivalent?

The two units used to measure biological effect and dose equivalent are the sievert (Sv) and the rem. The sievert is the SI (International System of Units) unit that quantifies the biological effect of radiation based on the type of radiation and its impact on living tissue. The rem (roentgen equivalent man) is the traditional unit used in the United States for measuring the same concept of dose equivalent. Both units take into account not just the amount of radiation absorbed (expressed in units like gray or rad) but also the potential biological effects, making them crucial for assessing health risks associated with radiation exposure.

The relationship between Sv and rem is that 1 Sv is equivalent to 100 rem, which underscores the biological significance of radiation exposure in dose assessment. This unit conversion allows for a comprehensive understanding of how different types of radiation can affect human tissues differently, further emphasizing the importance of dose equivalent in radiological protection. Other units like gray and rad measure absorbed dose, which do not account for the relative biological effectiveness of different radiation types.