Product Description
4-Gas Calibration Gas – 25 PPM H2S / 50 PPM CO / Methane (CH₄) 2.5% (50% LEL) / 19.5% O2 – 120L C-10 Cylinder
This 4-gas calibration gas blend is engineered for routine bump testing and full calibration of portable multi-gas monitors used in confined space and industrial safety programs.
Unlike atmospheric baseline blends containing 20.9% oxygen, this mixture contains 19.5% oxygen, the OSHA-defined oxygen-deficiency threshold. This allows verification of low-oxygen alarm activation while simultaneously validating toxic and combustible sensor performance.
Concentration profile:
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25 PPM Hydrogen Sulfide for toxic exposure sensor validation
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50 PPM Carbon Monoxide calibration for conservative CO alarm setpoints
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2.5% Methane (50% LEL) for combustible sensor accuracy
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19.5% Oxygen to simulate oxygen-deficient atmospheric conditions
This blend is commonly specified across wastewater facilities, oil & gas operations, utilities, and industrial manufacturing environments requiring OSHA-aligned confined space compliance.
The 120L cylinder format supports extended calibration cycles and high-frequency bump testing programs, reducing cylinder replacement intervals for large safety departments managing multiple monitors.
Gas Concentrations
| Component | Concentration |
|---|---|
| Hydrogen Sulfide (H₂S) | 25 PPM |
| Carbon Monoxide (CO) | 50 PPM |
| Methane (CH₄) | 2.5% (50% LEL) |
| Oxygen (O₂) | 19.5% |
| Balance | Nitrogen |
Cylinder Specifications
| Property | Value |
|---|---|
| Cylinder Size | 120L (4.2 ft³) |
| Pressure | 1050 psi |
| Cylinder Specification | C-10 |
| Cylinder Material | Aluminum |
| Gas Reactivity | Reactive |
Reactive multi-gas blends should be stored and used with compatible C-10 regulators to preserve mixture stability and maintain calibration accuracy.
Applications & Detector Compatibility
This 4-gas calibration gas supports most major portable multi-gas monitors used for toxic, combustible, and oxygen detection, including equipment from BW, MSA, Industrial Scientific, RAE Systems, and Dräger.
Common applications include:
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Oxygen-deficiency alarm verification
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High-volume daily bump testing
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Scheduled multi-monitor calibration programs
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OSHA confined space compliance
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Facility-wide gas detection fleet management
The 120L cylinder is ideal for continuous-shift environments and large industrial operations.
Need a Different Concentration or Cylinder Size?
If you do not see the exact gas mixture, ppm level, oxygen percentage, LEL value, or cylinder size required for your application, contact our calibration gas specialists. We can supply custom multi-gas blends built to your detector model, regulatory requirements, or site-specific hazard profile.
