What is the primary unit of measurement for radiation dose?

The primary unit of measurement for radiation dose is the Sievert. This unit is specifically designed to measure the biological effects of ionizing radiation on human tissue, making it a crucial metric in fields such as radiology and radiation protection. The Sievert takes into account the type of radiation and its impact on different types of tissues, thus providing a more comprehensive understanding of the potential harm arising from exposure to radiation.

The Gray is a unit commonly used to measure absorbed dose, which indicates the amount of radiation energy absorbed by a material, typically in terms of energy per unit mass. While it provides essential information about the physical dose received, it does not directly translate this into biological impact, which is where the Sievert plays a vital role.

The Rad is an older unit of absorbed dose that has been largely replaced by the Gray in most contexts, which means its relevance is waning in contemporary practice.

The Roentgen serves as a unit for measuring exposure to ionizing radiation in air specifically, but it does not directly indicate the dose absorbed by tissue, which makes it less applicable when assessing biological effects compared to the Sievert.