Key Considerations for Proper Use of Gas Detectors
① Identify all potential leakage points on the equipment to be monitored, analyze factors such as leakage pressure and discharge direction, draw a probe location distribution diagram, and classify risks into Grade Ⅰ, Grade Ⅱ and Grade Ⅲ according to leakage severity.
② Based on on-site airflow, wind direction and other site-specific factors, determine the propagation direction of combustible gas in the event of a large-scale leak.
③ According to the density of leaked gas (heavier or lighter than air) combined with air flow patterns, develop a 3D gas diffusion trend diagram, and formulate an initial layout plan for detectors at downstream positions of the gas flow.
④ Investigate whether the leakage at each point is a slow seepage or jet-type discharge. For slow seepage, detectors shall be placed closer to the leakage point; for jet leakage, detectors shall be set at a moderate distance from the source. Integrate all above conditions to finalize the layout plan, so that the required quantity and model of detectors can be estimated.
⑤ For areas with high risk of large combustible gas leakage, one detection point shall be installed every 10–20 meters in accordance with relevant regulations. For unattended, small pump houses operating intermittently, attention shall be paid to potential combustible gas leakage; normally one detector shall be installed on the leeward side.
⑥ In locations with hydrogen leakage risk, detectors shall be mounted on the plane above the leakage points.
⑦ For media with gas density higher than air, detectors shall be installed on the plane below the leakage points, with consideration of surrounding environmental conditions. Special attention shall be paid to setting safety monitoring points in areas prone to combustible gas accumulation.
⑧ In open environments where combustible gas escapes and diffuses, poor ventilation may cause local combustible gas concentration to approach or reach the lower explosive limit. Such locations must not be overlooked when arranging safety monitoring points.
