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Portable Gas Detectors

CO-04C Personal Carbon Monoxide (CO) Monitor with Hydrogen (H2) Compensation

Compact Carbon Monoxide (CO) Monitor with Low interference Sensor suitable for Hydrogen Rich Environments

Personal Single Gas Monitor for Carbon Monoxide (CO) 0-500ppm (0-2000ppm option) with Hydrogen Compensation (CO-H2) for reduced interference in Hydrogen Rich environments. 

Small and lightweight it is ideal for wearing in the "Breath Zone" around the head without interfering with work. It has 3 alarm levels which can be user set and a replaceable long life sensor with a 3-year warranty. CO-04C is durable and tough and designed for harsh environments and to deliver many years trouble free operation.

O4 series general features: 

  • Broad line up 10 models with more to follow. 
  • O2, CO, H2S, SO2, Dual O2 / CO, NH3, NO2, HCN, PH3 and CO-H2 models available now. 
  • CO2, CL2 and %LEL Models 2022. 
  • up to 9000 hours battery life.
  • IP 66/67 rated. 
  • Durable 7-meter drop test. 
  • ATEX. 

Series-04 Personal Single Gas Detectors

Product Features

Cost of Ownership:

Disposable gas detectors are low cost but users can suffer high failure rates, this can result in safety concerns. Users often find the cost of ownership often outweighs the small initial cost saving over a reliable renewable gas detector. Customers constantly have to replace failed units resulting in personnel down time and the lost productivity.


Facilities such as oil refineries, petrochemical storage facilities, water and wastewater treatment plants, pharmaceutical labs, Utilities, Fire-fghting and Chemical Plants are hazardous areas. workers and visitors need personal gas protection at all times without the addition of extra bulky equipment. Personal Single Gas Monitors are ideal for this.


Sampling method

Diffusion type

Principle of detection

Potentiostatic Electrolysis Method

Detection range

0 to 500 ppm(Display range 0 to 300 ppm / 300 to 2000 ppm)

Alarm setpoints

1st 20 ppm 2nd 100 ppm 3rd 1200 ppm TWA 25 ppm STEL 200 ppm OVER 2000 ppm

Type of alarm

Gas alarm / fault alarm

Display of alarm

Flashing lamp / intermittent buzzer sounding / gas concentration display blinking / vibration

Explosion protected construction

Intrinsic safety

Explosion-proof class

IECEx : Ex ia ⅡC T4 Ga (AAA alkaline), Ex ia ⅡC T3 Ga (Ni-MH)
ATEX : Ⅱ1G Ex ia ⅡC T4 Ga (AAA alkaline), Ⅱ1G Ex ia ⅡC T3 Ga (Ni-MH)

Ingress proof rating



Japan Ex, ATEX, IECEx, Brazil Ex

CE marking


Power source

AAA alkaline or Ni-MH (eneloop) batteries (x2)

Continuous operation

Approx. 6200 hours (AAA alkaline)
Approx. 4200 hours (Ni-MH)


Approx. 54 (W) x 67 (H) x 24 (D) mm (excluding projections)


Approx. 93g

Operating temperature range

-40℃ to +60℃ (no sudden changes)
(Approx. 15-minute temporry use environment: -20℃ to +50℃[no sudden changes])

Operating humidity range

0 to 95%RH (no condensation)
(Approx. 15-minute temporry use environment: 10 to 90%RH[no condensation])

Operating pressure range

80 to 120 kPa (80 to 110 kPa for explosion-proof range)

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