Abstract: International Commission on Radiological Protection(ICRP)issued new recommendations on radiological protection in 2012 which formally replaced the previous recommendations. In the new recommendation 118, which issued in 2012, ICRP included consideration of the detriment arising from non-cancer effects of radiation on health. These effects, previously called deterministic effects, are now referred to as tissue reactions. The commission considered the effects of radiation in normal tissues and organs-threshold doses for tissue reactions in a radiation protection context.