| Target Gas | The detector should explicitly support LPG components, especially propane and butane. | Propane lower explosive limit (LEL): approximately 2.1% by volume in air. Butane LEL: approximately 1.8% by volume in air. | A detector designed only for methane may not provide the intended response for LPG applications. |
| Detection Threshold | Choose adjustable or clearly specified alarm thresholds, with separate low- and high-level alarms where appropriate. | A common design point is a low alarm near 10% LEL and a high alarm near 20% LEL, but the applicable product and installation standard should determine the final settings. | Early warning can allow occupants or operators to shut off the gas and ventilate the area before a dangerous concentration develops. |
| Sensor Technology | Use a sensor type suitable for the environment, such as catalytic-bead or infrared technology for combustible-gas detection. | Catalytic sensors can be affected by oxygen deficiency or contaminants. Infrared sensors do not require oxygen for measurement and can offer good resistance to poisoning, depending on the design. | The sensor technology affects accuracy, service life, response behavior, and suitability for industrial conditions. |
| Response Time | Check the published response time, preferably including the T90 value or another defined test method. | The response time should be verified under the relevant performance standard and gas concentration; values vary by sensor and enclosure design. | A faster, verified response can reduce the time between a leak and an alarm or automatic protective action. |
| Alarm Outputs | Look for an audible alarm, visible status indicator, and relay or digital output when connection to a shut-off valve, exhaust fan, or control system is required. | Alarm sound levels and output behavior should be confirmed in the product documentation and assessed against the installation environment. | Multiple alarm interfaces help ensure that the warning is noticed and that corrective equipment can operate automatically. |
| Fail-Safe Functions | Prefer fault monitoring for sensor failure, power loss, wiring faults, calibration status, and end-of-life conditions where supported. | The device should provide a distinct fault indication and should not silently remain in an unreliable state. | Self-diagnostics help identify failures that may otherwise leave an area unprotected. |
| Hazardous-Area Certification | For classified hazardous locations, verify certification for the specific gas group, zone or division, temperature class, and protection method. | Common certification systems include ATEX under Directive 2014/34/EU and IECEx. Certification details must match the installation classification. | General-purpose equipment may create an ignition risk in areas where flammable gas can be present. |
| Performance Standard | Select a detector tested to a standard appropriate to its use, such as domestic, commercial, or industrial fixed detection. | Examples include EN 50194-1 for electrical apparatus used for the detection of combustible gases in domestic premises and IEC/EN 60079-29-1 for performance requirements of flammable-gas detectors. | The correct performance standard provides a more meaningful basis for comparing accuracy, alarms, and operating behavior. |
| Electrical and Product Safety | Check applicable electrical safety approvals, installation requirements, power-supply ratings, and regional conformity markings. | Depending on the market and product type, relevant requirements may include electrical safety, electromagnetic compatibility, and low-voltage conformity obligations. | Compliance supports safe operation and reduces the risk of interference or electrical faults. |
| Ingress Protection | Choose an IP rating suited to dust, moisture, washdown, and outdoor exposure. | For example, IP65 indicates protection against dust ingress and water jets from any direction; the rating does not by itself indicate hazardous-area approval. | Environmental protection helps preserve sensor performance and enclosure integrity. |
| Installation Location | For LPG, consider low-level mounting because propane and butane vapor are generally heavier than air. | Place the detector according to local codes and the manufacturer’s instructions, while avoiding dead-air spaces, ventilation outlets, steam, and direct contamination. | Correct placement is essential; even a certified detector may perform poorly if installed in an unsuitable location. |
| Calibration and Maintenance | Confirm calibration intervals, bump-test requirements, sensor replacement procedures, and availability of technical support. | Calibration frequency depends on the sensor, exposure conditions, regulatory requirements, and the manufacturer’s instructions. | Routine testing verifies that the detector can sense LPG and activate its alarms when required. |
| Documentation and Traceability | Require a declaration or certificate of conformity, test documentation, installation manual, operating limits, and a clear product identification label. | Certification numbers, gas coverage, ambient-temperature limits, electrical ratings, and approved installation conditions should be verifiable from official documentation. | Traceable documentation helps confirm that the selected detector is genuine, suitable, and installed within its certified limits. |