NukeWorker Forum
Reference, Questions and Help => Nuke Q&A => Instrument Q&A => Topic started by: CanadianRP on Mar 01, 2014, 08:35
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Could someone please help me understand the use of DACh on an iCAM? Specifically what does a reading in DACh mean for a worker? DACh as I understand it is analagous to total dose on a PAD, therefore how can the display go down as well as up? I realize this is probably a stupid question, just cant wrap my puny brain around it.
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DAC - Derived Air Concentration. DAC is calculated based off of nuclides in the air and their concentration of uCi/volume. One DAC is equal to 2.5 mREM.
DAC-hr is the amount of time exposed to that concentration.
As a sampler runs, in this case the iCAM, the concentration might change.
We'll use easy numbers for an example. The iCAM is turned on and sees an air concentration 10DAC of Co-60. Over the next hour, the display will trend up and finally show 10DACh after an hour. Then all of a sudden, the Co-60 goes away to 0 DAC. The display will trend down over the next hour until it reaches 5DACh. This is because if you were in the area for two hours, you would have seen 5DACh each hour, on average.
Hope this helps some.
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That is assuming that your annual dose is 5 Rem/working year (2000 hrs) = 2.5 mRem/dac X hours in area = dac/h. I am not sure, but if not mistaken, Canada does not currently recognize the DAC but is still using the MPC, which they calculate themselves and are not dictated to by the Feds. So if you working at a CA plant the DAC may not mean a lot. Could be wrong.
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Could someone please help me understand the use of DACh on an iCAM?
did that iCAM come with a manual by any chance? did You check the manual that came with that iCAM? RTFM; READ the manual please
and You can almost always get a free manual freely from the manufacturer site in pdf format.