108 RADIOISOTOPES IN BIOLOGY AND AGRICULTURE 



(a) knowledge of the amount and nature of the radioactivity received; 



(b) understanding of the chemical and physical behavior of the radioactive 

 material in the experiment to be performed; (c) repeated performance of 

 "dummy runs" to eliminate unforeseen difficulties; (d) forethought in 

 planning of operations; (e) proper use of suitable instruments; and 

 (/) common sense, vigilance, good housekeeping, and good work habits. 



In the Radiochemical Laboratory. It is not reasonable to set forth 

 rules and regulations applicable to all situations. Any rigid set of recom- 

 mendations would be unnecessarily stringent for some operations and 

 inadequate for others. The regulations required will depend upon the 

 amount and kind of radioisotopes employed and the number of people 

 involved. When only a few individuals are working with tracer amounts 

 of group I and II radioisotopes, the restrictions required will be minimal. 

 With larger operations it may be advisable to have definite regulations 

 and policies. The following are some illustrative recommendations (52 

 to 54) which may be used selectively as a guide for setting up working 

 rules : 



General: 



1. No unnecessary materials should be brought into the laboratory. 

 No unnecessary work should be done there. 



2. Eating, drinking, smoking, and the use of cosmetics in the laboratory 

 should be forbidden. Radioactive materials should not be placed in milk 

 bottles, soft-drink bottles, or other vessels that might be inadvertently 

 used for food purposes. 



3. Records should be kept of radioactivity brought into the building 

 and of its disposition. 



External Hazards: 



4. Radioactivity should be stored so that the general background is 

 less than of the order of 1 mr/hr. 



5. Work should be planned so as to minimize exposure to external 

 irradiation. In no case should the hands receive more than 1 r/week, 

 nor the whole body more than 300 mr/week. Pocket ionization chambers 

 and survey meters should be employed to estimate the dosages received, 

 and these values should be recorded. 



Contamination and Internal Hazards: 



6. Laboratory protective clothing (laboratory coats, gloves, goggles, 

 and shoe covers) should be employed as needed, but these items should 

 not be taken outside the laboratory and worn in clerical offices, rest 

 rooms, counting rooms, etc. No person who has breaks in the skin on 

 his hands should work with radioactive materials without using rubber 



