| 1 | LPG Detection Capability | Confirm that the detector is calibrated for propane, butane, or the specific LPG mixture used at the installation site. | IEC 60079-29-1 and IEC 60079-29-2 provide requirements and guidance for flammable-gas detectors. | Documented LPG calibration data, cross-sensitivity information, and an operating range expressed as %LEL. | 15% |
| 2 | Explosion Protection | Check whether the enclosure and electrical design are suitable for the hazardous area classification of the project. | IEC 60079 series; applicable ATEX or IECEx certification where required by the destination market. | A valid certificate with gas group, temperature class, protection method, and permitted ambient temperature clearly stated. | 15% |
| 3 | Measurement Accuracy and Stability | Review accuracy, repeatability, zero drift, temperature effects, humidity effects, and long-term calibration stability. | Performance claims should be supported by test reports and the applicable detector standard. | Complete technical specifications with test conditions, tolerances, and calibration intervals—not only a nominal accuracy figure. | 12% |
| 4 | Alarm and Response Performance | Compare response time, alarm repeatability, relay behavior, fault indication, data output, and alarm reset functions. | IEC 60079-29-1; alarm set points must also follow the site risk assessment and local regulations. | Published T90 response data, clear high/low alarm logic, sensor-fault alarms, and documented relay or digital communication behavior. | 12% |
| 5 | Ingress and Environmental Protection | Assess protection against dust, water, corrosion, vibration, temperature changes, and outdoor exposure. | IEC 60529 defines IP enclosure ratings; environmental claims should be supported by test documentation. | An IP rating appropriate to the installation environment, corrosion-resistant materials, and defined ambient limits. | 10% |
| 6 | Sensor Technology and Service Life | Identify the sensing technology, expected service life, poisoning risks, replacement procedure, and spare-part availability. | The manufacturer should provide sensor-specific operating, calibration, and maintenance instructions. | Replaceable sensor modules, documented consumables, realistic life-cycle information, and protection against known contaminants. | 10% |
| 7 | Quality Management and Traceability | Verify production controls, incoming inspection, final testing, calibration traceability, serial-number management, and corrective actions. | ISO 9001 is the internationally recognized quality-management-system standard. | A current, verifiable quality certificate covering the relevant manufacturing site and product scope. | 10% |
| 8 | Testing and Certification Evidence | Check certificate numbers, issuing bodies, model coverage, certificate status, and whether reports match the quoted configuration. | Certification records should be independently verifiable through the relevant certification database or issuing organization. | Complete certificates and reports supplied before purchase, with no unexplained model substitutions or expired documents. | 8% |
| 9 | Integration and Installation Support | Evaluate wiring diagrams, output options, communication protocols, mounting accessories, commissioning guidance, and technical response time. | Interfaces may include relay outputs, 4–20 mA, RS-485, or other protocols; compatibility must be confirmed project by project. | Clear manuals, application drawings, sample configurations, and pre-sales support for the intended control system. | 5% |
| 10 | After-Sales Service and Total Cost | Compare warranty terms, calibration service, replacement sensors, spare-part lead time, training, export documentation, and lifecycle cost. | Commercial terms are not defined by one global technical standard and must be recorded in the purchase contract. | Transparent warranty exclusions, available spare parts, documented maintenance procedures, and a stable service channel. | 3% |