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Previously published with subtitle: A guide for scientists and physicians. Includes bibliographical references and index. ISBN alk. Ionizing radiation—Safety measures. Radioactive substances—Safety measures. S5 It provides the information radiation users need to protect themselves and others and to understand and comply with governmental and institutional regulations regarding the use of radionuclides and radiation machines.
Concern with radiation hazards is not limited to those occupationally exposed to radiation. In fact, by far the largest number of people at risk from radiation exposure are members of the public; this group also receives the largest cumulative population dose. Most of their exposure comes from natural sources in the environment and from the use of radiation to detect and treat disease.
Other sources of radiation pollution that cause concern range from those with worldwide consequences, such as the Chernobyl accident and the atmospheric testing of nuclear weapons, to local effects from soil and water contamination by radioactive wastes.
Concerns over exposure to radiation are not limited to the high energies associated with nuclear processes, but include the permeation of the environment with low-energy electromagnetic radiations from radio and television antennas and radar installations. A new worry is exposure from close contact with cellular phones, as well as signals sent to and from their communications towers.
A large number of workers who require training in radiation protection, however, have minimal experience in these subjects, and their schedules are usually too full to allow for the luxury of extended reviews of the material. Thus, this manual is designed to obviate the need for reviews of atomic and radiation physics, and the mathematics has been limited to elementary arithmetical and algebraic operations.
Following a historical prologue, Part One introduces the sources of radiation in terms of the energy carried by the radiation, since energy imparted by radiation plays the central role in evaluations of radiation exposure. The coverage in this edition has been expanded to include the entire energy range of radiation exposure, so-called nonionizing as well as ionizing radiation.
Part Two presents the principles of radiation protection against ionizing particles and develops these in the context of the working materials of the radiation user. The central role of the energy imparted by ionizing particles in characterizing radiation exposure is explained and the properties of radiation are illustrated through examples with gamma radiation and beta rays electrons and positrons from common radioactive sources in research.
The heavy ionizing particles—alpha particles, protons, and neutrons—are then introduced. This part concludes with material for users of radiation machines in medical practice and research.
Part Four describes detection instruments and their use in making some of the more common measurements on radiation particles. Part Five presents practical Preface ix information, primarily for users of radionuclides. Part Six is concerned with the public health implications of the use of ionizing radiation in medicine and technology. Part Seven provides background on the nonionizing radiation in the electromagnetic spectrum along with an assessment of exposures from such sources as broadcast antennas, microwave towers, cellular phones, and radar.
Finally, Part Eight presents an overview of the major issues in radiation protection. The material in Part Two can be used to provide basic information for radiation users. Individuals planning to work independently with radiation sources or to administer radiation to human beings must receive additional training, including pertinent material in Parts Three through Six.
The book is well endowed with examples to illustrate and expand on the text. My approach to quantifying radiation doses deserves some explanation. The current method in vogue expresses radiation dose as a risk-based quantity, as proposed by the International Commission on Radiological Protection ICRP in By this method a nonuniform distribution of organ doses in the body from a given exposure to radiation is replaced by a single number, which is taken as the uniform whole-body dose with a comparable risk of producing a comparable detriment to health, and the spectrum of risks to health is based primarily on the risk of causing a fatal cancer.
Although both quantities were based on somewhat different paradigms, x Pre face they gave quite similar numerical values for the equivalent uniform wholebody dose. Their use has the advantage of simplicity and standardization and is well suited to express dose for regulatory purposes, or whenever a simple expression of the risk of radiation exposure is called for, as in consent forms. Cancer statistics, on which the formula for their calculation is based, have a high degree of variability; they change not only with better epidemiological studies but with improvements in treatments for the different types of cancer, necessitating changes in the constants in the formula.
Given the uncertainty of quantities based on biological effects, I have chosen to present the actual absorbed doses to organs when these data are available. I refrained from presenting effective doses except within a regulatory or nontechnical context, or when they are the only data available for a particular subject. The risk of lung cancer from exposure to radon gas in the home was a major concern in public health at the time of the third edition.
However, this concern has tapered off considerably, possibly because epidemiological studies have not demonstrated a strong relationship between exposure in the home and lung cancer, possibly because the public became accustomed to living with radon, possibly because the homeowner must pay the costs of remediation. Accordingly, I have expanded on the detailed discussions of radon presented in previous editions. The risk of harm from exposure to radiation is not generally considered by physicians when they prescribe radiological examinations, except when the patient is a pregnant woman or a young child.
I have expanded considerably the sections dealing with doses accompanying the use of radiation in medicine to help physicians make these decisions. I use Standard International SI units for dose and activity in this edition, except when reproducing verbatim data in the published literature given in traditional units.
However, I have retained the traditional unit for exposure, the roentgen. It is much easier to work with exposures expressed in roentgens than in the SI unit of coulombs per kilogram. Since publication of the last edition of Radiation Protection, the Internet has become an invaluable resource. In this edition, therefore, I have in- Preface xi cluded Internet addresses, where possible, to supplement, enrich, and update the material provided in the book. This manual originated from a training program in the safe use of radionuclides in research conducted at Harvard University that Dr.
Webster and I developed in The course was later offered also as a self-paced option. I am grateful to the many individuals who offered advice and assistance as Radiation Protection evolved through four editions. I am thankful to Michael Fisher, science and medicine editor at Harvard University Press, for his interest and support in bringing this edition to fruition. I enjoyed working with my editor, Kate Schmit, as she scrutinized the manuscript, correcting sins of grammar and punctuation and suggesting changes that made the text clearer and more readable, or improved the presentation of data.
Also on the Radiation Protection team were Sara Davis, who kept the author on track, and Christine Thorsteinsson, who looked after the production of the book. Finally, I am happy to express my appreciation to my daughter, Jean, my wife, Shirley, and my nephew, Mark Shapiro, for editorial comments regarding some of the personal views expressed here, and to my son, Robert, for stimulating me to make a personal statement.
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