Gas Data GM25-5 Gas Analyser
Portable Landfill & Ground Gas Analyser
The Gas Data GM25-5 is a compact portable gas analyser designed for routine ground gas monitoring and environmental site investigation.
Its fixed five-gas configuration measures methane (CH₄), carbon dioxide (CO₂), oxygen (O₂), hydrogen sulphide (H₂S) and carbon monoxide (CO). Atmospheric and static pressure measurements are also incorporated, providing the core parameters required for routine monitoring of ground gas conditions.
The GM25-5 also features hydrogen-compensated CO measurement, helping improve carbon monoxide measurements where hydrogen may otherwise interfere with the electrochemical sensor.
With no differential-pressure or internal flow measurement, the GM25-5 provides a straightforward option where the primary requirement is gas concentration and borehole pressure monitoring.
Key Features
Five gas channels: CH₄, CO₂, O₂, H₂S and CO
Hydrogen-compensated CO measurement
Atmospheric pressure measurement
Static pressure measurement
Compact handheld design
ATEX, IECEx and UKEx rated
Internal data logging
DataField GM25 Connect compatibility
Optional gas velocity and temperature measurement
8–12 hour battery life
User-replaceable battery pack
12-month service interval
Application guidance: Choose the GM25-5 for routine ground gas monitoring, contaminated land and site investigation where gas concentrations and pressure are required but integrated flow measurement is not necessary. Gas Data specifically identifies site investigation as an application.
Specification | Details |
|---|---|
ATEX Rating | ATEX, IECEx, UKEx II 2 G Ex ib IIB T1 Gb |
Dimensions | 260 × 100 × 75 mm |
Weight | 1.1 kg |
Ambient Temperature Range | -10°C to +40°C |
Aspiration Rating (minimum) | 300 mL/min |
Gas Measurements
Channel | Sensor Type | Range | Resolution | Accuracy |
|---|---|---|---|---|
CH₄ | IR | 0–100% | 0.1% | ±3.0% vol. (0–100%); ±0.3% vol. (0–5%) |
CO₂ | IR | 0–100% | 0.1% | ±3.0% vol. (0–100%); ±1.0% vol. (25–45%) |
O₂ | EC | 0–25% | 0.1% | ±0.5% vol. |
H₂S | EC | 0–5,000 ppm | 1 ppm | ±5.0% of reading or 75 ppm, whichever is greater |
CO | EC – H₂ compensated | 0–2,000 ppm | 1 ppm | ±5.0% of reading or 75 ppm, whichever is greater |
Pressure Measurements
Measurement | Sensor Type | Range | Resolution | Accuracy |
|---|---|---|---|---|
Atmospheric Pressure | Transducer | 800–1,200 mbar | 1 mbar | ±5 mbar |
Static Pressure | Transducer | ±250 mbar | 0.1 mbar | ±2.5 mbar |
The GM25-5 has atmospheric and static pressure measurement but no differential-pressure or integrated flow channel.