NDAWG comments on ICRP foundation documents The National Dose Assessment Working Group (NDAWG) was established in the UK in 2002. The aim of NDAWG is to bring together people and organisations with responsibility for, and/or an interest in, the assessment of radiation doses from the operation of the nuclear industry and from minor users of radioactivity. Further information on the work of NDAWG, including the current membership, is available on the website, www.ndawg.org. Members of NDAWG have considered the draft Foundation document of the International Commission on Radiological Protection (ICRP) as published on the ICRP website. The following set of comments represent the views of the majority of members but not necessarily the organisations that they represent. Committee 1 Task Group Report: C1 Foundation Document (FD-C-1). Biological and epidemiological information on health risks attributable to ionising radiation: a summary of judgements for the purposes of radiological protection of humans. NDAWG members found this a well written review of key issues relating to the biological effects of radiation. In particular it addresses some of the issues raised on the draft 2005 ICRP recommendations; i.e. the need to address uncertainties, taking account of the CERRIE report and using studies other than the A bomb LSS where possible. Section 7 and Table 7.1 were found to be particularly helpful Specific comments on the text: Page 28, there is a short paragraph on whether equivalent dose or radiation weighted dose should be used to express dose limits for skin and lens of the eye. This needs to be expanded to explain why it is an issue and to discuss the two alternatives. Page 29, In the discussion of effect in IQ following in-utero doses of a few tens of mGy do the authors mean that the shift in IQ in any individual would be of no practical significance because it would not materially impair their well-being? This needs to be clarified and should not be confused with issues of whether it can be detected. Page 56, Why is the wT value for the gonads applied to the mass weighted mean of the dose to the ovaries and testes? If it is the average risk to men and women that is required then it is the simple average of the two doses that should be calculated. Page 87, The possibility of a range of mutation components (MC) under different environmental contexts (e.g. where doses can be delivered to many generations of people) should at least be recognised. Page 95 (line 3233), The concept of breakpoint specificities has not been explained, so it is difficult to follow the argument about weighted PCRF’s.