644 



ADOLF F. VOIGT 



which they are to be used. Since the widespread use of tracers is just 

 beginning there is no large backlog of experience to guide the design- 

 ers of laboratories adapted for this purpose in the various fields of 

 biology, medicine, agriculture, and so on, in which tracers will be ap- 

 plied. Interest in the subject resulted in the symposium on the de- 

 sign of radiochemical laboratories at the April, 1948, American Chemi- 

 cal Society meeting {65). The difficulty with this and other such 



Samples for 

 ^ - counting 

 0.0005-0.05^0 



0.001 



0.01 



0.1 



I 



10 



100 



/XC. 



I 



nnc. 



10 



mc. 



100 

 nnc. 



10 

 c. 



100 



c. 



1000 

 c. 



MICROCURIE 

 LEVEL 



_l l__ 



Samples for 

 y - counting 

 0.05-5^0. 



X 



LEVEL OF RADIOACTIVITY 



MILLICURIE 

 LEVEL 



Experiment witti 

 /3 -trocer 

 O.OI^C.-50/ic. 



Cyclotron target 

 5 mc. - IC. 



^-tracer supply 

 for 10-100 experiments 

 0.1 /ic. - 5 mc- 



Experiment with 

 y- trocer 

 l/ic- 5mc. 



X 



X 



/-trocer supply 



for 10-100 experiments 



lO/ic. -500 mc 



31 



m 



MULTICURIE 

 LEVEL 



Scole of operotions in pro- 

 duction of rodioisotopes 

 5 mc. - lOOc. or more 



E 



_L 



Biological experimentation and medical 

 therapy 

 1/tc.- ic. 



X 



Possible fut 

 industrial rod 

 50 mc- - 1000 



ure 



iogrophiy 

 c. or more 



"i~~r 



T 



T 



Fig. 14. Approximate range of radioactivity encountered in various problems {66) 



presentations is that they have been largely discussions of practice 

 in Atomic Energy Commission laboratories, in which the activity 

 levels have been far above those of the ordinary tracer laboratory and 

 for which funds are available to a degree unheard of for the small re- 

 search or educational institution. In fact, it should be realized at the 

 outset that building and equipping a tracer laboratory may be consid- 

 erably more expensive than is the case for laboratories for other pur- 

 poses {66,67). 



Opinions on the design of laboratories and the extent of precautions 



