Gas sensors are detection devices that identify and measure gas concentrations in the environment. They convert chemical interactions with gas molecules into electrical signals for quantitative analysis. These sensors play a critical role in industrial safety, environmental monitoring, healthcare, and smart home systems by preventing gas leaks, ensuring air quality, and enabling process control.
| Type | Functional Features | Application Examples |
|---|---|---|
| Electrochemical | High accuracy, stable baseline, requires oxygen | CO detectors, O2 monitors |
| Semiconductor | Low cost, broad detection range, temperature-dependent | Indoor air quality sensors |
| Catalytic Combustion | Explosive gas detection, requires periodic calibration | Industrial methane detectors |
| Infrared (IR) | Non-contact measurement, high selectivity | CO2 HVAC monitoring |
| Photoionization (PID) | VOC detection at ppm levels, UV lamp required | Environmental pollution monitoring |
A typical gas sensor consists of: - Sensing element (metal oxide/electrolyte membrane) - Signal conditioning circuit (amplifier, ADC) - Housing with gas inlet ports - Temperature/humidity compensation module - Communication interface (UART/I2C)
| Parameter | Description |
|---|---|
| Detection Range | Measurable gas concentration span (ppm to %LEL) |
| Sensitivity | Signal change per gas concentration unit (mV/ppm) |
| Response Time | T90 response speed (3-300 seconds) |
| Accuracy | Measurement error margin ( 2-10%) |
| Operating Temperature | Functional range (-20 C to +50 C typical) |
| Long-term Stability | Drift specification (5-15% per year) |
| Manufacturer | Product Series | Key Features |
|---|---|---|
| Honeywell | XNX Universal Transmitter | Dual-sensor redundancy |
| Figaro Engineering | TGS2600 | Low-power VOC detection |
| Membrapor | Toxic Gas Sensors | Eletrochemical cells for Cl2 |
| Senseair | K-30 CO2 Module | NDIR technology, 30ppm accuracy |
| AMS (Austria) | ENS160 MOX Sensor | AI-based gas discrimination |
Key consideration factors:
Emerging development trends include: - Miniaturization through MEMS technology - Multi-gas detection using AI pattern recognition - Wireless self-powered IoT sensor nodes - Enhanced selectivity via nanomaterial coatings - Reduced cross-sensitivity through hybrid sensing methods
