GFM 436

The GFM 436 is an ATEX accredited instrument for site investigation, landfill gas control, and environmental regulation compliance monitoring. It is a fixed configuration, measuring the proportions of methane (by both volume and Lower Explosive Limit), carbon dioxide, oxygen, hydrogen sulphide and carbon monoxide in soil gas present in greenfield and brownfield sites, as well as land affected by landfill operations or other industrial contamination.

Additionally, hexane content can be measured to assist in areas with hydrocarbon vapours from spilt fuels, oils or other contaminants. This instrument has the additional capacity to measure gas pressure (differential and static) and flow rate (instantaneous and peak).

An optional temperature sensor can be plugged in for gas temperature measurements or, alternatively, a vane anemometer can be attached to measure the velocity in a gas extraction system pipeline.


Land remediation | Landfill gas and monitoring


  • GFM 436
  • GFM 436
  • GFM 436
  • GFM 436
  • GFM 436
  • GFM 436
  • GFM 436


  • Provides measurements of up to 6 gases
  • Can measure atmospheric, static and dynamic differential pressures
  • Small, portable design that is easy to hold in one hand
  • SiteMan PC software included
  • High-contrast LCD display
  • User-swappable battery pack
  • Battery life ranging from 8 to 12 hours, depending on model
  • Maximum charging time of 4 hours
  • Charger suited to your country
  • Protective weather-proof leather case
  • Supplied in a ready-to-go site kit
  • Annual recalibration interval
  • Factory-calibrated infrared sensor for measuring Hexane vapour
  • Detector (PID) correction factor for low levels of Volatile Organic Compounds (VOC)
  • Bi-directional measurement of instantaneous and peak borehole flow
  • Storage of 2 water level readings from DIP meter taken at each borehole
  • Manual data storage and programmable unattended data-logging functions
  • 3-tier hierarchical. 24-character alphanumerical labels for the naming of stored reading sets