Installation Height Requirements for Combustible Gas Detectors
1, Installation height requirements for combustible gas detectors
According to national standards such as GB 15322.3-2019 Combustible Gas Detectors Part 3: Portable Combustible Gas Detectors for Industrial and Commercial Use, the installation height of combustible gas detectors should be determined based on the density of the combustible gas.
2, Specific basis for installation height requirements
(1) The relationship between combustible gas density and air density
When the density of combustible gas is lower than that of air, the combustible gas will float upwards and accumulate above the space after leakage. Therefore, the installation height of the combustible gas detector should be 0.5-2 meters higher than the release source. For example, if the density of methane is lower than that of air, installing the detector in places where natural gas (mainly composed of methane) is used, such as the space above gas pipelines, can detect the leaked methane gas in a timely manner and issue an alarm before the concentration reaches a dangerous value.
When the density of combustible gas is greater than that of air, the combustible gas will sink and gather near the ground after leakage. The detector should be installed at a height range of 30-60cm above the ground. For example, combustible gases such as propane and butane have a higher density than air. In places where liquefied petroleum gas (mainly composed of propane, butane, etc.) is used, installing a detector at this height can effectively monitor gas leaks.
(2) Combustible gas detector special gas adaptation
Hydrogen: The installation location should eliminate static electricity and use intrinsically safe explosion-proof equipment.
Carbon monoxide: Avoid automobile exhaust outlets to prevent cross interference.
Composite gas: Clearly identify the detection objects of each sensor and set the alarm value according to the gas with the highest risk.
(3) Combining the physiological characteristics of the human body
In places where flammable gases leak, the degree to which the human body is affected by the gas varies at different heights. When the density of combustible gases is greater than that of air, installing a detector close to the ground can promptly detect the accumulation of combustible gases on the ground, avoiding injury to personnel due to gas diffusion; When the density of combustible gas is lower than that of air, the detector installed at a higher place can detect the accumulation of leaked gas above the space, issue an alarm in a timely manner, and remind personnel to take protective measures.
(4) Performance of combustible gas detector
The sensors of combustible gas detectors are sensitive to airflow and environmental factors. Installing at an appropriate height can ensure that the sensor is in a relatively stable working environment, improving the accuracy and reliability of detection. For example, by avoiding air disturbances near the ground and interference from hot air currents at the top, the sensor can stably detect the concentration of combustible gases, reducing the occurrence of false alarms and missed alarms.
