[ RadSafe ] Pb-210 Accumulation on Supply Fan Filters

[Randy.Redmond at cns.doe.gov]

Anyone else run across supply fan filters that have detectable beta-gamma that will not decay away like typical short-lived radon progeny?  Gamma spec shows a large Pb-210 peak.  Our thought process is there is an accumulation of Pb-210 on the filters because of the amount of air being moved and filtered;  the filters remain in use for several years; and the Pb-210 has a 20.4 year half-life.


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Randy Redmond
Y-12 Radiological Control
Radiological Engineering
Randy.Redmond at cns.doe.gov<mailto:Randy.Redmond at cns.doe.gov>
(865) 574-5640 Office
(865) 574-0117 Fax