XVII. RADIOACTIVE TRACERS 



641 



monitoring requires measuring (l(n-i(^es that can be worn or carried 

 by the worker without interfering with his manipulations. One of the 

 surest means of determining Iho radiation dosage that a worker has 

 received is the photographic badge. The film badge technique in- 

 volves a considerable knowledge of procedure in handling the film and 

 in preparing standards that the ordinary laboratory is not likelj^ to 

 have or to wish to acquire. It is gratifying that the isotopes distri- 

 bution program has been expanded to include on request a film badge 



(a) POCKET ELECTROSCOPE 



ib) POCKET ION CHAMBER 

 Cutaway view 



Cutaway view 



Outside 



Quartz 

 fiber 

 system 



«; 



Eyepiece 



Objective 



Contact point 



hreaded cap' 

 Window 



C 



Bakelite 

 case 



Outside 



Contact point 



Capsule 



containing 



desiccant 



CD 



Fig. 13. 



Plug capr 

 Several types of pocket radiation dosimeters. 



service for laboratories to which isotopes have been sent {19). This 

 cannot be said to give adequate protection since one knows about the 

 exposure only after it has been received. However, it does constitute 

 a worthwhile safeguard, since a person who has received an excess 

 dose as indicated by the badge could be relieved of such duty, or the 

 work could be revised to reduce the hazard. Some development has 

 been done on ring film holders to be worn on the hand likely to receive 

 a much greater dose than the remainder of the body; however, this 

 phase of the art is not in as advanced a state as that of film badges. 

 Several types of ionization chambers that can be worn by the 



