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04 Series Single Gas Detector

The 04 Series single gas monitor is designed to operate for many years with field replaceable sensors and filters.

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The 04 Series single gas monitor is designed to operate for many years with field replaceable sensors and filters. The 04 Series can be operated continuously for up to 9,000 hours on 2 AAA size alkaline batteries (depending on model). The 04 Series has 3 preset alarms that are user adjustable. Each version is also equipped with visual, audible, and vibration alarms as standard.

The replacement sensors are inexpensive, easily field replaceable, and are interchangeable with other popular RKI instruments like the GX-3R, GX-3R Pro, and GasWatch 3. Sensors have a life expectancy of over 3 years and are backed by a 3 year warranty.*

Each 04 Series monitor is impact, dust, and water resistant with an IP-67 ingress protection rating. 04 Series instruments are safe for use in hazardous locations, classified as intrinsically safe ATEX/IECEx and by QPS to U.S. and Canadian standards for Class I, Division 1, Groups A, B, C, and D atmospheres.

* 3 year warranty on material and workmanship including sensors   (1 year warranty for Ammonia and Chlorine sensors)


Tags: CO Carbon Monoxide Gas Detector, H2S Hydrogen Sulfide Gas Detector, O2 Oxygen Gas Detector, Sulfur Dioxide Gas Detector, Nitrogen Dioxide Gas Detector, Hydrogen Cyanide Gas Detector, Chlorine Gas Detector, Ammonia Gas Detector


  • Continuously operate for over one year (H2S & CO)
  • Toxic gases include: NH3, Cl2, HCN, NO2, PH3 & SO2
  • CO with H2 elimination
  • CO & O2 Dual Sensor
  • Field serviceable
  • Pocket size 2.1”x 2.6”x 0.9”, 2.8 ounces
  • Impact, dust, and water resistant (IP-67)
  • Replaceable rubber boot
  • Alligator clip with 360° rotation
  • Audible, visual, vibration alarms
  • Automatic backlight
  • Intrinsically safe, ATEX and C/US approvals
  • 3 Year warranty*


Sample Method Diffusion
Response Time T90 in 30 seconds
Alarm Gas Alarm: 1st, 2nd, 3rd (user adjustable), OVER alarm, STEL and TWA
Trouble Alarm: Sensor connection, low battery, circuit failure and calibration rang error
Battery Alkaline dry cell 2 AAA size
Display Digital LCD, gas name & concentration, auto backlighting during alarm, operation icon, battery icon
Alarm Flashing LEDs
Datalogging 10 second intervals, records alarms, alarm trends, gas readings, calibration & bump test history and instrument settings
Enclosure Dust and water resistant with IP-67 rating
Temperature -4 to 122°F
Humidity 0% to 90% relative humidity (non-condensing)
Intrinsic Safety UL: Class I, Division 1, Groups A, B, C, D
Size 2.1″ x 2.64″ x .94″
Weight 2.8 ounces
Warranty 3 Year warranty, 1 Year for Ammonia and Chlorine sensors

Sensor Specifications

Ammonia (NH3)
0 – 400 ppm
25.0 ppm/35.0 ppm
Carbon Monoxide (CO)  0 – 2,000 ppm 25 ppm/50 ppm
Chlorine (Cl2)  0 – 20 ppm  1.00 ppm/2.0 ppm
Hydrogen Cyanide (HCN)  0 – 30.0 ppm  5.0 ppm/10.0 ppm
Hydrogen Sulfide (H2S)  0 – 200.0 ppm  5 ppm/30.0 ppm
Nitrogen Dioxide (NO2)  0 – 20.0 ppm  2.0 ppm/4.0 ppm
Oxygen (O2)  0 – 40% Vol  19.5 % Vol/18.0% Vol
Phosphine (PH3)  0 – 20.0 ppm  0.30 ppm/ 0.60 ppm
Sulfur Dioxide (SO2)  0 – 100.0 ppm  2.00 ppm/5.00 ppm

Ordering Information

. Catalog No. Description Price Quantity .
Series 04 Ammonia gas detector
04 Series Carbon Monoxide
04 Series Carbon Monoxide
04 Series Chlorine gas detector
04 Series for Hydrogen Cyanide
04 Series Hydrogen sulfide
Nitrogen Dioxide 04 Series gas detectyor
04 Series for Oxygen
Phosphine 04 Series gas detector
Sulfur Dioxide 04 Series Gas Detector
04 Series CO/O2


04 Series Single Gas Monitor Datasheet

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