Whole Body Counters UNITED STATES ATOMIC ENERGY COMMISSION _Dr. Glenn T. Seaborg, Chairman_ _James T. Ramey_ _Dr. Gerald F. Tape_ _Dr. Samuel M. Nabrit_ _Wilfrid E. Johnson_ _ONE OF A SERIES ON UNDERSTANDING THE ATOM_ Nuclear energy is playing a vital role in the life of every man, woman, and child in the United States today. In the years ahead it will affect increasingly all the peoples of the earth. It is essential that all Americans gain an understanding of this vital force if they are to discharge thoughtfully their responsibilities as citizens and if they are to realize fully the myriad benefits that nuclear energy offers them. The United States Atomic Energy Commission provides this booklet to help you achieve such understanding. [Illustration: Edward J. Brunenkant] Edward J. Brunenkant Director Division of Technical Information Whole Body Counters/_{CONTENTS} 1 SENSITIVE DETECTORS 2 THE GENEVA COUNTER 8 THE LIQUID SCINTILLATION COUNTER 10 POTASSIUM-40 IN HUMAN BODIES 13 CRYSTAL COUNTERS 15 THE RADIUM STORY 17 A NEW BODY CONTAMINANT 21 PROTECTION OF LABORATORY PERSONNEL 24 SPECIAL USES 31 CONCLUSION 34 SUGGESTED REFERENCES THE COVER [Illustration: Whole Body Counters] This smiling youngster in the chute of a large whole body counter has just emerged from the opening (beyond her feet) of a hollow tank of scintillation liquid, where she lay while the radioactivity in her body was being “counted.” In a minute she will step into her slippers (on the ramp, right) and be ready for play. The sensitive, heavily shielded radiation-detecting equipment shown has many uses that are described in this booklet. THE AUTHORS [Illustration: John H. Woodburn] John H. Woodburn teaches chemistry at Walter Johnson High School in Rockville, Md. In the past he taught at Michigan State University, Illinois State Normal University, and Johns Hopkins University. He received his A.B. from Marietta College, his M.A. from Ohio State University, and his Ph. D. from Michigan State University. He is the author of the book _Radioisotopes_ (J. P. Lippincott 1962), which is a student’s introduction to this subject. [Illustration: Frederick W. Lengemann] Frederick W. Lengemann is associate professor of radiation biology at New York State Veterinary College, Cornell University. He received his B.S. and M.N.S. from Cornell and his Ph. D. from the University of Wisconsin. He has been research associate in radiation biology and assistant professor of chemistry at the University of Tennessee and formerly was a biochemist with the Atomic Energy Commission, Division of Biology and Medicine. Whole Body Counters By JOHN H. WOODBURN and FREDERICK W. LENGEMANN