Polonium 210 is an alpha paticle emitter that is used in commercial air ionizers for static control. Air ions of both polarities are produced in the air above the source to a distance of about 3 cm. These ions are attracted to charged surfaces and neutralize the surface. A company called NRD leases polonium sources in a variety of forms. One use that is similar to yours is the inclusion of small round sources in analytical balances to keep errors due to staic from being encountered. NRD can be reached at (716) 773-7634 and is in Grand Island NY.