Some weeks ago I’ve bought from an US eBayer some cilindrical shaped plastic scintillators. From wikipedia “A scintillator is a material that exhibits scintillation — the property of luminescence, when excited by ionizing radiation. Luminescent materials, when struck by an incoming particle, absorb its energy and scintillate”. This means that you can make a very sensible radiation counter using a scintillation material coupled with a PMT to detect his ligh pulses.
One is 1” diameter made of BC408, the other is 1-1/2″ of BC412.
This type of scintillators are very easy to use and cople to a photomultiplier tube, they just need some silicone coupling gel and a proper light tight enclosure to work. I’ve bought some otical coupling silicone too.
A simple way to determine that this pieces of plastic will work is to test with some UV light. If they are sensible to radiations they are sensible to UV too.
Some tech info about this type of plastic scintillators.
Here you can download the complete datasheet: sgc-bc400-404-408-412-416-data-sheet