Effluent Air Sampling at Spent Fuel Facilities

[ADAMSW@ORAU.GOV]

Dear Radsafers:

I'm looking for info concerning the sampling of tritium and iodine at dry
cask storage facilities (at low concentrations). 

I had planned on using a sampling train that consisted of a filter to trap
particulates, 2 cartridges of silica gel to trap the tritium, and an activated
charcoal canister to trap the iodine.  

My questions are:
1)  Will a significant amount of iodine be trapped in the silica gel?  I was
thinking that the silica gel would remove the water vapor (and hence
tritium) and that the iodine would pass through and be collected in the
activated charcoal.
2) Should I collect the samples in series or should they be collected
separately? Different flow rates required?
3) Has anyone tried this or has anyone a source of info? I'd be interested
in what mass of charcoal was used, flow rates, collection efficiency,
problems with humidity, etc.

Thanks in advance!!!

Wade Adams
ESSAP/ORISE
adamsw@orau.gov
(423) 576-0065
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