gasanalysers

Gas analysers are devices designed to determine the composition or concentration of gases in a sample. They span portable handheld models to large fixed systems used in laboratories and industrial plants. Common target species include oxygen, carbon monoxide, carbon dioxide, sulfur compounds, hydrocarbons, and a wide range of volatile organic compounds.

Most analysers operate by measuring either how gases absorb light, how they participate in chemical reactions that generate electrical signals, or how they separate components before detection. Common techniques include non-dispersive infrared (NDIR) absorption for CO2 and other gases; electrochemical sensors for toxic or oxidising gases; catalytic pellistors for combustible gases; metal oxide semiconductor sensors for broad ranges of gases; and photoionization detectors for VOCs. More complex analyses use gas chromatography or mass spectrometry, sometimes coupled with laser-based spectroscopy.

Applications of gas analysers include environmental monitoring, process control, safety and compliance in industry, emissions testing, indoor air quality, mining, healthcare, and research. They support tasks ranging from ambient air assessment to monitoring fugitive or process-related emissions.

Key performance factors include detection limit, linear range, response time, selectivity, cross-sensitivity, calibration requirements, and drift. Maintenance involves regular calibration with known gas standards, sensor replacement, and ensuring proper environmental conditions. Portable devices prioritize ruggedness and battery life; stationary systems emphasize automation and data integration.

Standards and certification vary by application and region, with safety-sensitive uses often requiring quality management, calibration traceability, and explosion-proof design where required.