The LFG-20 PLUS is a brand new portable, landfill site data logging gas monitor for simultaneous measuring of Methane, Carbon Dioxide, and Oxygen. These ranges are automatically selected according to the gas concentration in the sample and measurements are digitally displayed for each gas. The rate of decomposition of organic material varies within and between sites while the composition of landfill gas varies with time. The LFG-20 PLUS units are compact, lightweight, and are very easy to operate and maintain. The unit permits simple and precise measurements of Carbon Dioxide, Methane, and Oxygen in a sample drawn by an internal pump at 200 mL per minute. A battery charger, tubing and water/dust filters are supplied accessories. Yearly calibration, service, and installation of a new Oxygen sensor only takes a few days. An optional data logger stores all measurement along with time and date. Windows based software and USB interface for PC connection allows continuous logging of all parameters. The units are typically under $700 and are user-programmable to configure the logger to suit a wide variety of applications. The logged data can easily be downloaded and used to produce graphs or be exported to alternative software such as spreadsheets and can be set to continuously log with live PC link and graphical formatting.