§ Malcolm Bruce
To ask the Secretary of State for Health what systems the National Radiological Protection Board has in place to update their radiation risk models; when the risk models were last reviewed; and when the risk models were last updated. 
§ Yvette Cooper
The National Radiological Protection Board (NRPB) conducts a rolling programme of research and scientific review in order to update advice on the health effects of ionising radiation and the appropriate risk models for assessing these effects. NRPB has issued formal advice in the documents of the NRPB (Vol. 4(4), 1993; Vol 6(1), 1995). The NRPB's advisory group on ionising radiation will report shortly on the risks of leukaemia.
Scientific reviews and reports on risk models are also undertaken by NRPB staff in the context of a United Kingdom input to the work of the International Commission on Radiological Protection, the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), and a committee of the National Academy of Sciences of the USA. The UNSCEAR 2000 report on radiation effects and risk models included input from NRPB staff acting as consultants. This report represents the current international scientific consensus on the health effects of ionising radiation.
§ Malcolm Bruce
To ask the Secretary of State for Health what the National Radiological Protection Board's policy is on the radiation risk from(a) external and (b) internal low level radiation; when this policy was developed; and when it is next subject to review. 
§ Yvette Cooper
The policy of the National Radiological Protection Board is to provide advice on the health effects of exposure to external and internal radiations which is based on the totality of relevant scientific information. These sources of information include assessment of doses to critical tissues in the body, epidemiological (human health) investigations and knowledge of the fundamental biology of radiation action on cells and tissues. In circumstances where direct epidemiological information is lacking, judgments are developed using knowledge of doses to different tissues, the biological effectiveness of different radiations and the relative radiation sensitivity of different tissues.
Risk modelling procedures used by NRPB have been developed over many years often in conjunction with international bodies such as the International Commission on Radiological Protection (ICRP) and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR).
Current risk modelling procedures are based essentially on the 1990 Recommendations of ICRP and subsequent advice published by NRPB (Documents of the NRPB, Vol 4(4), 1993 and Vol 6(1), 1995). Scientific review of the data and procedures for assessing the health effects of external and internal radiations is an on-going process. The general policy of NRPB is to review and revise these procedures in the light of accruing scientific knowledge and therefore no specific date for revision may be given.