We shall pay attention to the following aspects when using combustible gas detectors:
① Before using a combustible gas detector, first identify all leakage points of the equipment, analyze the leakage direction, pressure and other relevant factors, draw a layout diagram for probe installation positions, and classify leakage risks into Grade Ⅰ, Grade Ⅱ and Grade Ⅲ according to leakage severity.
② Based on the density of leaked gas and the flow trend of ambient air, formulate a three-dimensional gas diffusion trend diagram, and work out the initial layout plan for detector installation at the downstream of the gas flow path.
③ Determine the diffusion direction of combustible gas in the event of a large-scale leakage by taking into account on-site wind direction, airflow and other site-specific conditions.
④ Analyze the leakage mode of each point, i.e. slow seepage or jet ejection. For slow seepage, install the detector closer to the leakage point; for jet ejection, place it at a proper distance away from the leakage source. Finalize the installation layout after comprehensive assessment, so as to estimate the required quantity and model of detectors to be purchased.
⑤ For sites with hydrogen leakage risk, mount the detector on the horizontal plane above the leakage point.
⑥ If the site is prone to massive combustible gas leakage, arrange one detection point every 10 to 20 meters in accordance with relevant regulations. For small pump houses with intermittent operation, install an additional detector at the leeward side to guard against potential gas leakage.
⑦ In open environments where combustible gas diffuses freely, poor ventilation may cause local gas concentration to approach or reach the lower explosive limit (LEL), which shall never be overlooked.
⑧ When deploying combustible gas detectors for gases heavier than air, install the instruments on the lower horizontal plane below the leakage points and evaluate surrounding environmental conditions comprehensively.
Special attention shall be paid to the arrangement of safety monitoring points in areas prone to combustible gas accumulation.
As reflected by the working principle of combustible gas detectors: electromagnetic interference will distort detection signals and lead to measurement deviations; physical collision or vibration may cause open circuits and complete detection failure; excessive ambient humidity or water intrusion into the device can result in short circuits or changed circuit resistance, triggering detection malfunctions.
