CHAPTER 3 



HEALTH PHYSICS AND RADIATION PROTECTION 



Nomenclature and Units: Specific ionization; Energy of radiation; Alpha rays; Beta 

 rays; Gatniua rays; Absorption of radiation; Units of radioactivity; Units of radiation 

 dose; External Hazards: Maximum permissible levels; Shielding; Internal Hazards: 

 Maximum permissible levels; Avoidance of internal hazards; Classification of radioiso- 

 topes; Decontamination : General hand washing; Rigorous hand washing; Clothing; Lab- 

 oratory tools and glassware; Various surfaces; Waste Disposal: Isotopes with a half-life 

 not greater than 2 weeks; Isotopes of intermediate half-life used in small quantities; Car- 

 bon 14; Instrumentation for Radiation Protection. Summary and Suggested Work- 

 ing Rules. 



In 1896, shortly after the discovery of X rays, the damaging properties 

 of ionizing radiation were recognized as manifested by epilation, dermati- 

 tis, and ulceration of the skin. The more insidious aspects — the long 

 latent period, the production of malignancies, the possible shortening of 

 the life span, the extreme sensitivity of the developing embryo, and the 

 genetic effects — were to be observed later as more and more people were 

 to work with X-ray machines and radioactive materials and as animal 

 experiments were undertaken. In the early 1920's various national and 

 international committees established permissible levels of exposure to 

 ionizing radiation from X rays and radium. As a result of the production 

 of large amounts of radioactive materials by particle accelerators and 

 nuclear reactors, it became evident about 1942 that special attention 

 should be given to the hazards of radiation. The science of health physics 

 thus came into being, with the development of philosophies, personnel, 

 and procedures aimed at the prevention of radiation damage to man. 

 References (1 to 11) may be consulted for a historical account of radiation 

 effects and for a listing of various committees and their recommendations 

 as published by the National Bureau of Standards. The handbooks from 

 the Bureau should be readily available to all persons working with radio- 

 active material. 



The practical utilization of atomic energy will be governed to a large 

 extent by the establishment of reasonable but adequate tolerances and 

 procedures. Safety must be the first consideration. Very few investi- 

 gations would be worth the risk of injury to the experimenter. Similarly, 



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