We have di f f e red from the standard NRC style in this volume in two minor ways. First, because the book is intended as a ready reference, we have spelled out all abbreviations the first time (and only the first time) they appear in each chapter and in each of the very lengthy main subheadings of Chapter 9. A list of abbreviations is included on page viii. Second, we have provided all measures of radiation and/or radioactivity as conventional units followed in parentheses by the equivalent measure expressed in Système Internationale units. We have wor ked to ensure that all information in this.
