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RKI Instruments GX-3R Pro Five Gas Monitor

$1,695.00 $1,290.00
(You save $405.00)
GX-3R Pro

Product Description

RKI Instruments GX-3R Pro Five Gas Monitor

The GX-3R Pro is the world’s smallest 5-gas monitor weighing only 4.58 ounces and fits in the palm of your hand (2.9” W x 2.6” H x 1.06” D). It simultaneously monitors and displays 5 different gases. In addition to monitoring standard confined space gases, LEL, O2, CO, & H2S, the GX-3R Pro has a 5th channel where you can add infrared or toxic sensors. Two of the four sensor slots have interchangeable sensors providing flexible configurations, which can easily be changed in the field.

The GX-3R Pro comes equipped with Bluetooth wireless communication, man-down alarm, the choice of alkaline or rechargeable power supply, and a 3 year warranty.  The Lithium-ion battery pack will operate for 25 hours and will fully charge in 3 hours.

The GX-3R Pro utilizes Bluetooth communication to display direct gas readings from the instrument to a phone app, which is available free on either iOS or Android phones.  Automatic notifications can be programmed to send text or email messages, if there is an alarm event from the GX-3R Pro.

Safety supervisors will appreciate the non-compliance indicator. The instrument flashes it’s 3 LED lights every 30 seconds in the following conditions; if the instrument has not been bump tested, or if calibration is due, or if there was a gas alarm event. The 3 LED lights will continue to flash once every 30 seconds until the non-compliance condition has been resolved. The 30 second interval is adjustable.


  • Smallest & lightest 5 gas monitor
    • 2.9″ W x 2.6″ H x 1.06″ D , 4.58 ounces
  • Simultaneous detection of 5 gases
    • LEL, O2, H2S, CO, and other optional sensors
    • H2 Compensated CO sensor available
  • Simple 2-button operation
  • Bluetooth communication with iOS & Android App
  • Non-Compliance Indicator
  • 3 user adjustable alarm levels
  • Panic Alarm
    • Tap instrument twice
  • Man Down Alarm
  • Impact resistant body
  • Large full dot, auto-backlit display with auto-rotation
  • Stealth mode for law enforcement
  • Field replaceable sensors & filters
  • Water and dust resistant design, IP66/68
  • 3 Year Warranty

The Riken Keiki GX-3R PRO (available April 2019) is the smallest and lightest 5 Gas Space monitor available today. The Riken Keiki GX-3R pro is in comparison to the GX-3R capable of detecting five gas types separately. With a size of 73 cm wide, 65 cm high and weighing 140g, the Riken Keiki GX-3R PRO can be defined as true craftsmanship. The Riken Keiki GX-3R PRO is perfect for confined space work as its size means it does not interfere with work even if it is attached in the breathing zone.

Battery Life:

The Riken Keiki GX-3R PRO has a build in extended battery mode which allows the monitor to be used continuously for up to 40 hours before recharging. IP66/68 compliance, as well as a three-year sensor warranty, allows the Riken Keiki GX-3R PRO to be used with confidence.


The GX-3R PRO has 3 preset alarm settings per gas and an over alarm which allows the alarms to be set at EH40 workplace exposure limits plus an additional alarm for a higher detection range. The GX-3R PRO internal data logger allows 3600 event logs and 300 hours which can be read out using an IrDA link. A loud 95dB alarms buzzer is also included.

Operating temperature range:

The Riken Keiki GX-3R PRO has an operating temperature range of -40 degrees Celcius to +60 degrees Celcius (intermittent) or -20 degrees Celcius +50 degrees Celcius (continuous) allow the GX-3R PRO to be used in many different environments and applications.

New Confined Space Monitor has 3 sensor design

The GX-3R PRO uses 3 compact sensors including a brand new Electro-chemical Oxygen Sensor. The Riken Keiki GX-3R PRO Confined Space Monitor will detect, Combustibles, Hydrogen Sulphide, Oxygen as well as Carbon Monoxide. A 3-year sensor warranty is now standard.



Detectable Gases
Gas Measuring Range
Preset Alarms
Sensor Slot 1: Carbon Monoxide (CO) & Hydrogen sulfide (H2S) *Interchangeable
H2S / CO Dual EC 0 ~ 2000 ppm
(1 ppm)
± 5% of reading
or ± 5 ppm CO
A1: 25 ppm│ A2: 50 ppm
A3:1200 ppm│TWA: 25 ppm
STEL: 200 ppm
0 ~ 200.0 ppm
(0.1 ppm)
± 5% of reading
or ± 2 ppm H2S
A1: 5 ppm│ A2: 30 ppm
A3: 100 ppm│TWA: 1.0 ppm
STEL: 5.0 ppm
EC 0 ~ 200.0 ppm
(0.1 ppm)
± 5% of reading
or ± 2 ppm H2S
A1: 5 ppm│ A2: 30 ppm
A3: 100 ppm│TWA: 1.0 ppm
STEL: 5.0 ppm
H2 Compensated
EC 0 ~ 2,000 ppm ± 5% of reading
or ± 2 ppm CO
A1: 25 ppm│ A2: 50 ppm
A3: 1200 ppm│TWA: 25 ppm
STEL: 200 ppm
Sensor Slot 2: Combustibles (Methane as standard)
CH4 / HC Catalytic 0 ~ LEL (1% LEL) ± 5% of reading
or ± 2 % LEL
1st: 10% LEL │ 2nd: 25% LEL
3rd: 50% LEL │ Over:100% LEL
Sensor Slot 3: Oxygen (O2)
O2 EC 0 ~ 40.0% Vol.
± 0.5% O2 Low 1: 19.5%│ Low 2: 18.0%
High: 23.5%│ Over: 40.0%
Sensor Slot 4: Toxics & CO2 *Interchangeable
SO2 EC 0 ~ 100.0 ppm
(0.05 ppm)
± 10% of reading
or ± 5 % of full scale
A1: 2 ppm│ A2: 5 ppm
A3: 100 ppm│ TWA: 0.25 ppm
STEL: 0.25ppm
*CO2 IR sensor available AUG 2019
CO2 % IR* 0 ~ 10.0% Vol.
± 5% of reading
or ± 2 ppm
A1: 0.50% Vol.│ A2: 3.00% Vol.
A3: 4.00% Vol.│ TWA: 0.50% Vol.
STEL: 3.00% Vol.
CO2 ppm 0 ~ 10,000 ppm
(20 ppm)
A1: 5,000 ppm│ A2: N/A
Common Specifications
Sampling Method Diffusion sampling standard
(hand aspirator or clip-on motorized pump optional)
Display Full dot LCD with Autobacklight
and Autorotation
Alarm Types Gas Alarm Trouble Alarm
• 2 increasing
• Overscale
• O2
• Sensor
• Low battery
• Circuit error
• Calibration
range error
• Cal or bump
due alarm
• Man Down Alarm
• Panic Alarm
Display of Alarm Gas Alarm Trouble Alarm
• Flashing
• Continuous
buzzer (100
db @ 30cm)
• Flashing gas
• Vibration
• Flashing
• Intermittent
buzzer (95
db @ 30cm)
• Display
of error
Operating Temp. & Humidity -20°C ~ +50°C
[ -4°F ~ +122°F ] 10 to 90% RH, non-condensing (continuous environment)
-40°C ~ +60°C
[ -40°F ~ +140°F ] 0 to 95% RH, non-condensing
(temporary environment)
Response Time Within 30 seconds (T90)
Power Source Config Li-ion Alkaline
4-gas + EC 25 hours 16 hours
4-gas + IR 16 hours 7 hours
Dimension & Weight 2.9” W x 2.6” H x 1.06” D
(Approx. 73 W x 65 H x 26 D mm), 4.58oz (with rubber boot)
Case Material Explosion proof, dust and water resistant to IP-66/68 (2m,1h) approval. Drop height 23 ft
Bluetooth Communication BLE: with iOS and Android phone app: RK Link
Datalogging Logs user ID, station ID, Calibration & Bump Test history, Alarm Events &
Alarm Trends
Standard Accessories Alligator clip, protective rubber boot, charger, calibration adapter
Optional Accessories • Padded carrying case
• RP-3R Attachable sampling
Pump with 4” rubber nipple, 10’
hose and probe (up to 40’ hose
• USB to IrDA downloading cable
for datalogger
• SDM-3R calibration station
• Hand aspirator
Safety Design / Approvals ATEX, CSA (Pending)
Warranty Three years material and workmanship including sensors

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