Precautions to take when installing toxic and noxious gas detectors
1. Precautions during application
Once the fixed installation of the toxic gas alarm is in place, its position is not easily changed. The following points should be considered when applying it specifically.
(1) Identify the possible leakage points of the device to be monitored, analyze their leakage pressure, direction, and other factors, and draw a distribution map of probe positions. According to the severity of the leakage, it is divided into three levels: I, II, and III.
(2) Based on specific factors such as airflow direction and wind direction in the location, determine the direction of toxic gas leakage when a large amount of leakage occurs.
(3) Based on the density of the leaked gas (greater than or less than air), combined with the trend of air flow, a three-dimensional flow trend chart of the leak is synthesized, and an initial point setting scheme is made at the downstream position of its flow.
(4) Study whether the leakage state at the leakage point is micro leakage or jet like. If it is a minor leak, the location of the point should be closer to the leak point. If it is a jet leakage, it should be slightly away from the leakage point. Based on these conditions, develop a final site plan. In this way, the quantity and variety that need to be purchased can be estimated.
(5) For places with significant toxic gas leaks, according to relevant regulations, a detection point should be set up every 10-20 meters apart. For unmanned small and discontinuous pump rooms, attention should be paid to the possibility of toxic gas leakage, and a detector should generally be installed at the lower air outlet.
(6) For places with hydrogen leaks, detectors should be installed on the plane above the leak point.
(7) For media with a gas density greater than air, the detector should be installed on the lower plane below the leakage point, and attention should be paid to the characteristics of the surrounding environment. Special attention should be paid to the setting of monitoring points for places prone to the accumulation of toxic gases.
(8) For open environments where toxic gases diffuse and escape, if there is a lack of good ventilation conditions, it is also easy to make the toxic gas content in the air of a certain area close to or reach the lower explosive limit concentration. These are safety monitoring points that cannot be ignored. According to the analysis of the on-site accident, more than half of it was caused by incorrect installation and calibration. Therefore, it is necessary to introduce the precautions for correct installation and calibration to reduce malfunctions.
2. Precautions for installing toxic gas alarms
(1) The alarm probe is mainly a detection element that contacts the combustion gas sensor, consisting of a platinum wire coil wrapped with aluminum oxide and adhesive to form a spherical shape, with rare metals such as platinum and palladium attached to its outer surface. Therefore, be careful during installation to avoid damaging the probe.
(2) The installation height of the alarm should generally be between 160-170cm to facilitate daily maintenance by maintenance personnel.
(3) The alarm is a safety instrument with sound and light display functions, and should be installed in a place that is easy for workers to see and hear, in order to timely eliminate hidden dangers.
(4) There should be no strong electromagnetic fields (such as high-power motors and transformers) around the alarm that may affect the operation of the instrument.
(5) The installation position of indoor probes should also vary depending on the density of the measured gas. When the density of the measured gas is less than the air density, the probe should be installed 30cm away from the roof in a downward direction; On the contrary, the probe should be installed 30cm above the ground in an upward direction.
