State standards for radiation of space flights

Abstract

A set of standards for radiation safety of manned space flights has been worked out and officially adopted in the U.S.S.R. to be used as guidelines in designing radiation protection systems for manned missions intended for exploration of near-earth and interplanetary space. These guidelines cover models of various radiation sources, methods and constants involved in shielding calculations and testing, methods of radiation dosimetry, a human body model for tissue dose calculations and, most importantly, radiation safety requirements for space flight durations up to 3 yr. According to these documents, space flight radiation safety is characterized by the level of radiation risk at the end of flight. The flight radiation risk is defined as the increment of the probability of death during flight from somatic radiobiological effects of in-flight exposure. The maximum permissible radiation risk at the end of flight is found to depend on flight duration. A method of space flight radiation risk calculation has also been elaborated which takes into account both random radiation exposure events (proton solar flares) and occasional exposures of space crews to high radiation fields.