the risk assessment: Shesh N. Rai, Yong Wang, and Jan M. Zielinski. Their contributions were important in the development of chapter 3 and appendix A.

Sixth, the committee is especially grateful to Rosalyn Yalow, an original committee member whose health prohibited her from serving as a final author of the study. Dr. Yalow was especially effective in insuring that the committee not overlook the influence of cigarette-smoking on the lung-cancer problem.

Seventh, this report has been reviewed by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the National Research Council's Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the authors and the National Research Council in making the published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The content of the review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their participation in the review of this report: Gregg Claycamp (University of Pittsburgh School of Public Health), Merril Eisenbud (deceased), Robert Forster (University of Pennsylvania School of Medicine), Naomi Harley (New York University Medical Center), Werner Hofmann (University of Salzburg), Maureen Henderson (University of Washington), Richard Hornung (University of Cincinnati), Donald Mattison (University of Pittsburgh School of Public Health), Suresh Moolgavkar (University of Washington), Lincoln Moses (Stanford University), Louise Ryan (Harvard University School of Public Health), and Duncan Thomas (University of Southern California). Although the individuals listed above have provided many constructive comments and suggestions, responsibility for the final content of this report rests solely with the authoring committee and the National Research Council.

The committee appreciates the assistance of the Board on Radiation Effects Research (BRER) staff who supported the committee's work, especially Doris Taylor for her assistance with meeting and travel arrangements and Amy Noel O'Hara and Dennis Gleeson, Jr., for their attention to the details of manuscript preparation.

The BEIR VI committee has faced many challenges in preparing this report. Committee members are hopeful that the report will meet the needs of the EPA as it considers risk management strategies for indoor radon and also will be informative to the public as homeowners make decisions about testing for radon and lowering radon concentrations in their homes.

JONATHAN SAMET, M.D.

CHAIR, COMMITTEE ON HEALTH EFFECTS OF EXPOSURE TO RADON, (BEIR VI)