[ RadSafe ] Kr-85

[JGinniver at aol.com]

In a message dated 23/09/2005 15:28:37 GMT Standard Time,  
Jim_Hardeman at dnr.state.ga.us writes:

Due to  the 10.7 yr half-life of Kr-85, noble gas decay doesn't help a whole 
lot in  minimizing releases of Kr-85, not does it buy you much with Xe-131m 
(11.8  day), Xe-133 (5.2 day), or Xe-133m (2.2 day). It DOES however, help to  
minimize releases of Kr-85m (4.5 hr), Kr-87 (76 minutes), Kr-88 (2.8 hr),  
Xe-135 (9.1 hr) and Xe-138 (14 minutes).



It's been awhile but my recolletion was that the charcoal beds on PWRs were  
designed to delay the release of noble gases by about 90 days so you will see 
a  significant reduction in all but the Kr-85.
 
Regards,
    Julian