Fluence-to-effective dose conversion coefficients for male astronauts.

The problem of the reliable estimation of astronauts' radiation exposure doses in deep space is very important and relevant in connection with the accepted space research programmes. The effective dose value based on ICRP Publication 103 presents too conservative an estimate of an astronaut's radiation risk. A more realistic dose can be calculated on the basis of relationships between the radiation quality factor and linear energy transfer or linear energy or Z*/β , according to the NASA concept.