calibration of tritum monitor

["E.PAUL CARTER" <CARTER@TUNL.TUNL.DUKE.EDU>]

bt
I have a TRITON 1125 tritum monitor in working order which
requires calibration. The unit was made by Johnston 
Labs. Inc. which I have been unable to locate.
Is there a facility that can calibrate the unit for me
and approx cost. (the cal cyl I used is way past it
usable half life __methane/h3 mix). and I don't want
to purchase another.
Please respond to carter@tunl.duke.edu
regards
paul carter
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