respiratory protection

["Stephen A. Costigan" <costigan@lanl.gov>]

I would like some RADSAFE feed back on the following situation. When
monitoring airborne contamination with CAMs having a continuous display, one
can pin down the time of a "puff" release and observe a spike in airborne
contamination levels. One can also observe that if you change the filter
after the "puff", the airborne level is back down indicating there was short
release and good air clearance.  Assume the average airborne level for the
duration of the job is well below what you would recommend as a cut-off for
the respiratory protection you're using (based on the protection factor).
Also assume that for the 10 minute period where you do have airborne
radioactivity, the airborne exceeds the cut-off you have established for
your respiratory protection by a factor of 2 to 5. 

If you're simply performing air sampling then your most likely integrating
over the duration of the job and there would be no problem evident. However,
with continuous monitoring you can observe the transient situation. Do you
immediately go up to the next level of resp. protection? Can you live with a
small spike above your protection factor? How big of a spike before it's a
problem? How long? (For the sake of simplicity, ignore all the helpful
advice you would like to give about engineered controls, containment,
contamination control etc.)

I am interested in hearing how radsafers handle time-averaging for airborne
contamination vs. respiratory protection?
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Steve Costigan
ESH-1 Health Physics Operations
PO Box 1663  MS J519		phone: 505-667-0066
Los Alamos National Laboratory	fax: 505-667-2964
Los Alamos, NM 87545		e-mail: costigan@lanl.gov
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