Patent · US Expired

Discriminating electret radioactivity detector system and method for measuring radon concentration

US5093570A · kind A · utility

7Cited by
9References
36Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 22, 1990
Grant dateMar 3, 1992
Priority date
Expiry dateFeb 22, 2010

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S250/02
  • WIPO fieldEnvironmental technology
  • WIPO sectorChemistry

Abstract

The detector system includes three substantially similar detectors each of which includes an ionization chamber having a pedestal therein mounting a charged electret. Two chambers are completely sealed except for an equalization aperture. The third detector has filtered inlet openings, which permit entry of radon gas, and responds to gamma rays and radon gas. Each detector is a canister including a lid having a round base surrounded by a cylindrical wall. The canister body is a circular base surrounded by a cylindrical wall that nests within the lid with a telescopic fit. A cylindrical pedestal assembly rests on the lid base and concentrically sandwiches the canister body between the pedestal assembly and lid. A press-fit holds these three elements together. The charged electret is mounted on the platform by a retaining collar that holds the electret with a press-fit. By keeping the three units together until the test starts, one of the sealed containers can have the charge on its electret measured at the beginning of the test in order to provide a baseline measurement. At the end of the test, the charges on the other two electrets are measured and provide a gamma ray background me…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.