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An analyzer for determining helium-4 in the parts-per-billion range

Filetype[PDF-601.99 KB]


  • English
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    Details:

    • Personal Author:
      Holland, Philip W.
    • Corporate Authors:
      United States. Bureau of Mines.
    • Description:
      "The Bureau of Mines has developed a trace helium analyzer for determining helium-4 in the parts-per-billion range. The instrument is used for analyzing pure gases, laboratory-prepared standards, and atmospheric samples. Accuracy at the 95-pct confidence level in the 50- to 20,000-ppb range is within +/-2 ppb or +/-0.4 pct, whichever is greater. The minimum detectable helium-4 concentration is calculated to be 5 ppb. The analyzer consists of a modified helium leak-detector mass spectrometer, a laboratory-built sample inlet system, and a liquid-nitrogen-cooled charcoal trap. A programmable integrator and event-control module make automatic operation possible. The portability of the analyzer allows it to be used in the field.The Bureau of Mines has developed a trace helium analyzer for determining helium-4 in the parts-per-billion range. The instrument is used for analyzing pure gases, laboratory-prepared standards, and atmospheric samples. Accuracy at the 95-pct confidence level in the 50- to 20,000-ppb range is within +/-2 ppb or +/-0.4 pct, whichever is greater. The minimum detectable helium-4 concentration is calculated to be 5 ppb. The analyzer consists of a modified helium leak-detector mass spectrometer, a laboratory-built sample inlet system, and a liquid-nitrogen-cooled charcoal trap. A programmable integrator and event-control module make automatic operation possible. The portability of the analyzer allows it to be used in the field." - NIOSHTIC-2

      NIOSH no. 10003355

    • Subjects:
    • Series:
      Report of investigations (United States. Bureau of Mines) ; 8853
    • Document Type:
      Report
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