Complex sentence: The sievert is used for quantities such as equivalent dose, effective dose, and committed dose and represents the effect of external radiation from a source outside the body, and also for internal irradiation, which is due to inhaled or ingested radioactive substances.
Split into simpler sentences: The sievert is used for quantities such as equivalent dose, effective dose, and committed dose. It is used to both represent the effect of external radiation from sources outside the body, and also for internal irradiation, which is due to inhaled or ingested radioactive substances.