What is the meaning of dose equivalent in radiation safety?

Dose equivalent is a crucial concept in radiation safety because it provides a way to quantify the biological effect of ionizing radiation on human tissues. It considers not just the amount of energy deposited (absorbed dose) but also the type of radiation involved and its potential impact on health.

The absorbed dose, measured in gray (Gy), indicates the amount of energy deposited in a tissue per unit mass. However, different types of radiation (such as alpha particles, beta particles, or gamma rays) have different biological effects. To account for these differences, a quality factor is applied to the absorbed dose, which adjusts the measurement according to the relative biological damage each type of radiation can cause.

By multiplying the absorbed dose by the quality factor, we arrive at dose equivalent, typically measured in sieverts (Sv). This adjustment makes dose equivalent a more useful metric for assessing risk and establishing safety standards in radiation protection, allowing for a better comparison of the potential health risks associated with different types of radiation exposure.