Re: Ni-63

["Richard J Sobilo" <rjsobilo@beckman.com>]

Rafi:

I've done a huge number of wipe tests on these types of ECDs and have found
about10-15% of them with removable contamination, sometimes with much
larger levels than you've found. After a while you come to expect some
contamination since these devices are heated and take some chemical abuse
from the analyte. I wouldn't worry too much about what your finding there
(~300-400 cpm). At this level they are still not considered 'leaking
sources' and with an efficiency of probably approaching 80% for your LSC
you are below 1000 dpm/wipe (an generally accepted contamination level for
unrestricted release).

Rich Sobilo
rjsobilo@beckman.com