Sievert Nuclear Regulatory Commission permits the use of the units curie, rad, and rem alongside SI units, the European Union European units of measurement directives required that their use for "public health ... purposes" be phased out by 31 December 1985. An older unit for the dose equivalent is the rem, still often used in the United States. One sievert is equal to 100 rem: Sievert The sievert (symbol: Sv) is a derived unit of ionizing radiation dose in the International System of Units (SI) and is a measure of the health effect of low levels of ionizing radiation on the
Biological effects of radiation on the epigenome stimulus can cause beneficial adaptations in an organism. The ionizing radiation stimulates repair proteins that are usually not active. Cells use this new stimuli to adapt to the stressors they are being exposed to. In biology, the bystander effect is described as changes to nearby non-targeted cells in response to changes in an initially targeted cell by some disrupting agent. In the case of Radiation-Induced Bystander Effect, the stress on the cell is caused by ionizing radiation. The bystander effect can be broken down into two catagories, long range bystander effect and short range bystander effect. In long range bystander