The GX-3R is the world’s smallest 4-gas monitor, weighing only 3.52 ounces and can comfortably be clipped within a worker’s breathing zone. It simultaneously monitors and displays LEL combustibles, O2, CO (H2 compensated CO also available), and H2S.

It represents the latest evolution of gas detection technology utilizing a new generation of microsensor technology.

Sensor Improvements

  • LEL sensor has a unique design with two active filaments in one sensor to increase its resistance to silicone poisoning – a common problem with other previous sensors.
  • NEW O2 sensor is electrochemical with a 3 to 5-year life span.
  • H2S and CO are now available in a combo microsensor.

The instrument also incorporates compliance testing by activating its 3 LED lights every 30 seconds (adjustable interval) if the instrument has not been bump tested if calibration is due, or if there was a gas alarm event. These LED lights will continue to flash once every 30 seconds until the non-compliance condition has been resolved.

Available Accessory: RP-3R Sample Draw Pump

Category: ,


  • Smallest & lightest 4 gas monitor
  • Simultaneous detection of 4 gases (LEL, O2, H2S & CO; H2)
  • Compensated CO sensor available)
  • Simple 2-button operation
  • Non-Compliance Indicator
  • Alarms: audible, visual, & vibration
  • 3 user-adjustable alarm levels
  • Impact-resistant body with removable rubber boot
  • Large LCD Auto-backlit display
  • 25 hours of operation (Lithium-ion battery)
  • Field replaceable sensors & filters
  • Water and dust resistant design, IP66/68
  • 3 Year warranty

  • Dimensions: 2.2 W x 2.55 H x 1.02 D inches (H 200 x W 68 x D 52 mm)
  • Weight: 3.52 ounces
  • Alarm Types:
    • Gas alarm: 3 Increasing alarms, STEL, TWA, overscale alarm. O2 decreasing/increasing
    • Trouble: Sensor disconnection, low battery, a circuit error, a calibration range error
  • Sample Method: Diffusion sampling standard (hand aspirator or clip-on motorized pump optional)
  • Response Time: Within 30 Seconds (T90)
  • Display: Digital LCD displays with 7 segments plus 14 segments plus icon
  • Audible Alarm: Gas Alarm 100 dB @ 30 cm; Trouble Alarm 95 dB @ 30cm
  • Power Source: Lithium-ion battery, Approx. 25 hours after a 3-hour full charge
  • Operating Temperature: -20°C to +50°C (-4°F to +122°F )
  • Relative Humidity: 10 t0 90% RH non-condensing
  • Warranty: Three-year material (including sensors) and workmanship

Sensor Type Measuring Range Resolution
Dual H2S/CO H2S: 0 - 200.0 ppm
CO: 0 - 2,000 ppm
H2S: 0.1 ppm
CO: 1 ppm
CO (H2 Compensated) 0 - 2000 ppm 1 ppm
LEL 0 to 100% LEL 1% LEL
O2 0 - 40.0 % Vol. 0.1 %Vol.

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Schedule a demo with the experts at Electrogas to experience firsthand the innovative safety solutions we offer. Our team is dedicated to providing personalized demonstrations tailored to your specific needs and requirements.

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