Here is the proper procedure for tritium sampling.


1. Obtain a small filter paper.
2. Wipe the customs package without getting it to dirty.
3. Place the filter in the sealable vial within thirty second of
wiping.

Otherwise the vapor evaporates and the sample is degraded seriously.

And then the hard part becomes fast analysis. A special liquid
scintillant is addable to the sealed vial and scintillation quanta
emitted are countable.

A coincident decay is the tritium signature. and two quanta seen at the
exact sam time on two 180 degree spaced PMT's counts the decay.

And so low cost is the only issue, a simple detector is about 10K
making each customs office require a single H-3 counter!!!!

Hand held tritium counting is possible with gas flow proportional
counters. A probe placed on the package surface can directly count H-3.

And so the basic design is placed here for public domain purposes.




----------O----------O---------O--O--O--O--------

A wire with bubbles of gas space are placed in a gaussian shielded open
faced probe.
Each "O" is a small plastic bubble.

And the density of "O"'s is sufficient to form the basic plastic layer.
And parrallel wires form the flat plate of plastic bubbles.

A gas diffusion fills the bubbles with proper gas like propane.

And each little bubble forms the collection volume ensuring the gases
presence at th eproper concentration!

A computer control bubble maker could layout the entire thing like an
ink jet printout!

So computer made face plates are possible making very inexpsneive H-3
detectors for US Customs.