TESTING RADIUM CAPSULES FOR RADON LEAKAGE.

Abstract

Sealed radium sources are used, predominantly, for medical purposes in this country. Expensive spills of the radium salt are on record. Careful handling, periodic examination, testing for radon leakage, and re-encapsulation should be provided for all sealed radium sources. Aside from tue potentially severe health hazard, careful attention to maintenance of the hermetic seal of radium sources is important for 2 reasons: a spill of the finely divided radium salt can be highly expensive to clean up, and the source does not deliver tue gamma dose expected of it unless the radon daughters are in equilibrium with the parent radium. A new, more sensitive, electrostutic precipitation method of leak testing sealed radium sources has been developed and field tested for several years. This method is far more sensitive than earlier methods and a time-saver during field surveys. Radiological safety surveys in 24 hospitals and 5 doctors' offices revealed 37 leaking radium sources out of a total of 684 leak tested (total of 4,318 mc). Leaking sources contaminate storage safes, handling equipment and applicators. It is concluded that sealed radium sources should be tested for radon leakage annually and that such sources should be routinely re- encapsulated every 10 years tomore » relieve the internal gas pressure caused by inevituble accumulation of helium when alpha particles capture electrons and become helium atoms. (auth)« less