The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 29, 1980
Filed:
Jan. 12, 1978
Richard C Smith, O'Hara Township, Allegheny County, PA (US);
Ira E Kanter, Monroeville, PA (US);
Westinghouse Electric Corp., Pittsburgh, PA (US);
Abstract
Alpha particles emitted from radon 220, a daughter product formed from the decay of thorium, are prevented from reaching an alpha particle detector by enclosing the detector in a volume into which alpha-emitting radioactive gases can only enter through a semipermeable membrane at least about 10 mg/cm.sup.2 in thickness. The enclosed volume must be between 30 and 2000 cm.sup.3 and the (AP)/(VL) ratio must be between 10.sup.-7 and 10.sup.-5. Also, the detector must be positioned so as to expose it to gas from the membrane for a distance of at least 2 cm through a solid angle of at least one steradian.