SOME ASPECTS OF FALLOUT OF CONCERN TO CIVIL DEFENSE A report of the ad hoc Subcommittee on Fallout Advisory Committee on Civil Defense NOTICE The work of the Advisory Committee on Civil Defense is approved by the Governing Board of the National Research Council, acting in behalf of the National Academy of Sciences. Such approval reflects the Board's judgment that the work of the Committee is of national importance and appropriate with respect to both the purposes and resources of the National Research Council. The members of the Subcommittee selected to prepare this report were chosen for recognized scholarly competence and with due consideration for the balance of disciplines appropriate to the project. Responsibility for the detailed aspects of this report rests with the Advisory Committee on Civil Defense. Each report issuing from a committee of the National Research Council is reviewed by an independent group of qualified individuals accordi to procedures established and monitored by the Report Review Committed of the National Academy of Sciences. Distribution of the report is ~ approved, by the President of the Academy, upon satisfactory completion of the review process.