Introducing PETREL
Quadrupole Mass Spectrometer

...with high performance membrane inlet




PETREL, the Bay Instruments quadrupole mass spectrometer, is designed for versatility in gas analysis using membrane inlet and other gas inlet devices. Our novel design offers one click pump-down of inlets during start-up or change-overs. Filament and vacuum losses are prevented using software and hardware that monitors the inlet. A quick-connect fitting that adapts to multiple devices allows easy change-over of inlets, including our high precision membrane, membrane cuvette and capillary gas inlet.

...with membrane inlet cuvette


  • Mass range: 0 to 100, 200, or 300
  • Detectors: Faraday and C-SEM
  • Ion source: Gas tight
  • Detection limit min: C-SEM (hPa) 1 · 10-14 hPa
  • Scan speed: MID 2 ms – 60 s/amu
  • Sensitivity for Ar: C-SEM 200 A/mbar
  • Sensitivity for Ar: Faraday 5 · 10-4 A/mbar


  • Automated inlet valves for pre-evacuating inlets
  • Automatic protection of filament and SEM from inlet failure
  • Precision* of ion currents: 0.1%
  • Precision* of gas ratios: 0.03%
  • 15N,18O abundance (air): 1 per mil

* C.V. of triplicate measurements


Unique data display for high precision and convenient data processing

  • Single mouse click retrieval of ion currents and ratios
  • Zooming capability to visualize signal stability
  • Provides optimal visualization for instrument tuning