Both reviewers from the Norwegian Radiation Protection Authority are agreed that, all in all, this is a very well written report containing interesting and contemporary information regarding health risks attributable to ionising radiation. However, we would like to suggest some minor changes/ clarifications that we believe will help the reader’s understanding of this report. • The reviewers miss the inclusion of an up-to-date glossary in this report. A glossary containing concise definitions of the different terminology used in the report would be of great benefit to the reader. • Page 27, lines 1114-1126: This paragraph contains important information and could be written more clearly. “Effective maximum RBE” could also be an ideal candidate for definition and explanation in a glossary section, as is the term “occult hypersensitivity” (line 1121). • The reviewers would like to see an improved explanation of the term “estimates of selection coefficients (s)” on lines 2606-2607. • The use of the symbol “.” in place of “×” in representations of numbers e.g. line 3330 “(= 0.13.10-2 to 0.25.10-2.Gy-1; average: 0.19.10-2.Gy-1);” might be confusing for the reader. This use of the symbol “.” appears in several places in the report.