460 ISOTOPIC TRACERS AND NUCLEAR RADIATIONS [Chap. 19 



conditions. Those rules which appear advisable regardless of the level of 

 activity are indicated by asterisks. 



*1. All operations with active gaseous and hot liquid materials must be 

 performed in well-ventilated hoods. When possible the entire process should 

 be carried out in the hood and benches reserved for preparing reagents and 

 apparatus. 



2. Active material is never used in a procedure until a dummy run with 

 inactive material has been made first and the procedure shown to be com- 

 pletely satisfactory. If changes are made in apparatus or the process, 

 dummy runs should be repeated. 



*3. No procedure is permitted which involves danger of oral contamination 

 whether by dust, liquid, or volatile materials. This is especially important 

 for alpha activities and materials that remain fixed in the body. 



4. Bench tops and hood floors are to be covered with absorbent paper 

 before work is begun. Contaminated paper is to be removed and placed in 

 active waste cans. In any case the paper should be replaced at regular 

 intervals. 



5. All glass receptacles containing highly active material must be placed 

 and handled in stainless-steel trays, unless the receptacles have been provided 

 with lucite shield containers. 



6. Hot liquids must not be poured unless proper precautions are taken to 

 contain spilled and spattered material. 



*7. All active materials not in immediate use are to be kept in the storage 

 vault. 



*8. All covers and shields must be kept in place except when transferring 

 materials. 



*9. Distillates must be condensed and collected if any active material is 

 volatile. 



10. All active materials entering or leaving the laboratory are to be moni- 

 tored and pertinent data recorded. 



*11. Active material is never poured down sink drains but is placed in 

 shielded jars to be properly disposed of. 



*12. Spilled or spattered material must be cleaned up immediately. Dust 



must be avoided by using wet cleaning materials which are then wrapped in 



clean paper and disposed of in the active waste cans. The area is to be 



monitored immediately thereafter. 



*13. Working areas are to be monitored before and after completion of work. 



14. The laboratory is to be given periodic cleaning by a wet procedure. 



15. Laboratory coats or coveralls must be worn in the laboratory but must 

 be removed when leaving. Such apparel must be immediately replaced 

 when contaminated. 



