Gas-Ranger Natural Gas, CO/Hydrogen Sulfide (H2S) and Oxygen (O2) Detector

Rugged, All-Weather Gas Detectors

All Gas-Ranger models are now available for purchase through our online store


Gas Ranger - Portable Gas Detector Models and Specifications Models and Specifications - PDF

Gas Ranger - Portable Gas Detector Short Guide Short guide (abbreviated operating manual) - PDF

MODELS RGA-411 & RGA-412

The Model RGA-411 will display "air-free" CO readings in flue gas.

Accurate, Rugged and "Smart" Gas Detectors for Utilities
The all-weather, Gas-Ranger detectors, specifically designed for gas and other utility personnel, can be used to track gas leaks, bar-hole, and to monitor ambient air for natural gas, carbon monoxide, hydrogen sulfide, and oxygen. Two types of natural gas sensors, electrochemical carbon monoxide/hydrogen sulfide (CO/H2S) and oxygen sensors, a built-in 2 liter/minute pump, and microprocessor control provides accurate and fast gas, CO/H2S, and oxygen readings. The Gas-Ranger is used for leak location, bar holing, outdoor / indoor differential CO readings, flue gas tests, and verification of safe air in confined and enclosed spaces. Now you can carry one detector and do the whole job both indoors and outdoors.

Gas-Ranger Operational Description
Bar hole gas measurements are made easily and consistently with the detector's built-in pump, automatic timer and memory. All gases are monitored continuously and the unit alerts aubibly and visually (e.g. GAS, CO, LoO2, HiO2) when one or more gases are outside their alarm limits. All models have a TRACK GAS scale for quick leak locating sensitive to 0.005% GAS (0.1% LEL or 50 ppm)

The Model RGA-412 displays all gas readings as %GAS while the Model RGA-411's TRACK GAS scale reads gas levels as a percent of the lower explosive level (LEL) scale displaying in units of %LEL. Both models automatically select the optimal sensor (catalytic combustion or thermal conductivity) for highest accuracy and read percent gas over the full range (0.005 to 100%). CO in flue gas and in ambient air is measured with 1 ppm resolution and with specificity when the detector is used with the external interference filter. H2S is also displayed on the CO scale when the detector is used without the interference filter. Oxygen is displayed with 0.1% resolution over a 0 to 40% range.

The detector comes with standard 6 inch fiberglass probe connected to a dust and water block filter on a 5 foot straight hose, a manual, a laminated short guide to operation, a set of batteries, and a shoulder strap. Also included is:

Automatic Calibration (A-CAL TM)
Automatic calibration is a standard feature built into all Gas-Ranger detectors. Using Bascom-Turner's calibration gas, delivered either manually or by an automatic gas dispenser, detectors are automatically calibrated in about 30 seconds.

Lifetime Limited Warranty
There is a lifetime limited warranty on the detector's electronics and a three year limited warranty on sensors applicable to detectors and sensors in the USA. The pump and accessories are warranted for one year.

Intrinsically Safe
UL listed for hazardous locations, Class I, Div. 1, Groups A, B, C, and D atmospheres.


  • Docking Calibration (D-CAL) - An optional system for large users offers calibration at docking stations. Calibration data, sensor sensitivities, and usage time are centrally available to help manage risk. Faxes reminding users of due or overdue calibrations are sent automatically.

  • Standard and Extended Duty Flue Probes - for flue gas sampling lasting 5 minutes with the standard probe or longer with the extended duty probe.

  • Bar Hole Probes - clear plastic, fiberglass, and stainless steel long probes for underground leak location.

  • Surface Vacuum Probe - for surface surveys (see picture below).

  • Instrument Case - for storage of detector and accessories.

Gas-Rangers Come In Several Models Specifically Designed For Detecting:

Gas-Ranger being used with metal bar hole probe
Gas-Ranger's high speed internal pump
is ideal for leak classification.