Which unit compares the biological effects of different types of radiation?

The unit that compares the biological effects of different types of radiation is the rem (Roentgen equivalent man). The rem takes into account not only the amount of radiation absorbed but also the biological effect that type of radiation can have on human tissue. This means that different types of radiation, such as alpha particles, beta particles, and gamma rays, can have different levels of effect on living organisms, and the rem unit incorporates a quality factor to appropriately reflect these differences.

In contrast, rad (radiation absorbed dose) measures only the absorbed dose of radiation regardless of the biological effects. Gray (Gy) is another unit that denotes the amount of radiation energy absorbed but lacks biological weighting. Radon (Rn), on the other hand, is a naturally occurring radioactive gas and is not a unit of measurement for radiation's biological effects. Therefore, the rem is the preferred unit when assessing potential biological consequences from various types of radiation exposure.