tritium monitors

[Les Slaback <lester.slaback@nist.gov>]

Costs: anywhere from $6k to >17k for grossly similar units.

Sensitivity:
typically 1 uCi/cc upwards, BUT....
FemtoTech and Overhoff both spec 0.1 uCi/cc systems.
Overhoff has some interesting technology to reduce the radon background to
achieve stable results at these lower levels.  I would be interested in
hearing from anyone who has one of these systems.

Berthold has a system that mixes the sample stream with P-10 to count in a
proportional mode, and achieves <0.1 uCi/cc, and has some neat low/high
beta energy separation capability (useful for simultaneously monitoring H-3
and Ar-41), but is uses a lot of P-10.  We have one of these and it has
worked well on various special projects.

Disclaimer:  the above are the personal musings of the author, and do not
represent any past, present, or future position of NIST, the U.S. government,
or anyone else who might think that they are in a position of authority. 
Lester Slaback, Jr.  [Lester.Slaback@NIST.GOV] 
NBSR Health Physics 
Center for Neutron Research 
NIST 
Gaithersburg, MD  20899 
301 975-5810