Gas leak detectors must be installed in the boiler room

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In boiler rooms that use natural gas as fuel, combustible gas alarms must be installed, which are linked to emergency shut-off valves. According to the GB 50041–2008 Code for Design of Boiler Rooms, combustible gas alarms are required. When there are vapors of flammable or toxic gases evaporating in the air, the detector’s signal is transmitted immediately via cable to the alarm control unit, which displays the gas concentration. When this concentration exceeds the set alarm threshold, the control unit emits audible and visual alarm signals as well as sending out control signals to activate devices such as fans in order to eliminate the hazard, thereby ensuring safe production in the factory and preventing accidents. For detecting natural gas leaks in boiler rooms, it is recommended to use the CRNDL-1 industrial explosion-proof wall-mounted combustible gas alarm manufactured by Nideley. http://img.mp.sohu.com/upload/20170613/4053fcf539dd45c597d25bd16078f960_th.png　The importance of installing natural gas alarms in boiler rooms. The main component of natural gas is methane, which is a flammable and explosive gas. If natural gas leaks and comes into contact with an open flame, static electricity, lightning, or improper handling, it can cause explosions and fires. In enclosed spaces, this can lead to oxygen deprivation, suffocation, and even death. Installing a natural gas alarm can effectively prevent explosions and fires, thereby protecting property and the lives of workers. The importance of installing natural gas alarms in boiler rooms. The function of a natural gas alarm is to detect the concentration of natural gas leaks; once this concentration exceeds the safe level, it immediately issues an alarm to alert workers to take safety measures. From its function, it is easy to see the importance of gas detectors. If a gas alarm is installed, in the event that we forget to turn off the gas supply, once the concentration of natural gas reaches the level set by the alarm, it will alert us to a gas leak, prompting us to take action; this can largely prevent explosions from occurring. The importance of installing natural gas alarms in boiler rooms. To ensure the reliability of product performance, we recommend that users carry out regular maintenance and calibration of the device throughout its usage period. If you have any questions, please consult a professional technician. 　　A natural gas explosion occurs in an instant – within a thousandth of a second – as a combustion process that generates high temperatures (up to 3000°C) and high pressures; the speed of the shock wave can reach 300 m/s, resulting in significant destructive force. 　　If natural gas leaks come into contact with an open flame, static electricity, lightning, or improper handling, it can lead to explosions and fires. In enclosed spaces, this can cause oxygen deprivation, suffocation, and even death, resulting in immeasurable losses to the safety of production operations as well as to people’s lives and property. 　　Possible natural gas leaks in gas boiler rooms and analysis of their causes. In addition to leaks resulting from employees’ improper operations, as well as natural or external factors, there are mainly the following causes for natural gas leaks in gas boiler rooms. 　　Leaks in indoor and outdoor gas pipelines: poor construction quality during installation, or corrosion of the pipelines over time due to prolonged use. 　　Leakage in the boiler body: This occurs due to failure to follow the relevant technical requirements during the initial design or installation of the gas boiler. For example, the walls of the boiler may not be welded properly; the boiler may not be dried according to the relevant technical requirements after construction, or the cracks in the bricks forming the boiler walls may occur due to rapid temperature changes, resulting in poor sealing; gas boilers may experience significant vibration during operation, which can cause the welds to come apart or lead to cracks in the insulation layer of the boiler walls; access holes, explosion-proof doors, and manholes may not be closed properly; and the boiler may shut down automatically while in operation. 　　Burner leakage: caused by design issues or improper installation and commissioning; after long-term operation, the air-fuel ratio becomes unbalanced, resulting in changes in the combustion conditions. 　　Leakages at components such as controls, regulators, and meters, as well as at their connection points: Frequent operation of these components can lead to inflexible switches or poor sealing, while vibrations during boiler operation may cause the connection points to loosen and result in natural gas leaks. Poor quality of these control, regulatory, and measuring components can also lead to poor sealing and gas leaks; in addition, aging of flanges, gaskets, sealants, etc. can cause leaks. 　　When there is a severe leak of natural gas in the boiler room, the following phenomena occur: The operating pressure of the natural gas changes. 　　A strong airflow sound can be heard near the source of the leak. 　　The handheld alarm will emit an abnormal sound. 　　When the leakage is significant (concentration is high), the fixed alarm will issue an automatic alert and the exhaust fan will turn on automatically. 　　In severe cases, disasters such as explosions or fires in the boiler itself or natural gas pipelines can occur. 　　Precautions against natural gas leaks in gas boiler rooms: During the design and construction of gas boiler rooms, it is necessary to follow strictly the relevant provisions of GB50041-1992, the \"Code for Design of Boiler Rooms\". Professional design firms with the appropriate qualifications, as well as construction units with the necessary skills, should be involved in the design and construction process, so that the boiler rooms are constructed in a standardized manner from the outset, thereby eliminating potential safety hazards and preventing natural gas leaks. 　　(1) Establish and improve various safety management systems in the workshop. Over the past few years, the workshop has gradually established and improved various regulations such as the \"Safety Operation Rules for Gas Boiler Rooms,\" the \"Emergency Response Plan for Gas Boiler Accidents,\" the \"Work Safety Responsibility System,\" the \"Routine Inspection System,\" the \"Operating Standards for Gas Boiler Rooms,\" the \"Fire Safety Inspection System,\" the \"Equipment Maintenance System,\" the \"Entry/Exit Registration System,\" as well as responsibility systems for personnel in different positions, thereby strengthening the safety management in the workshop. 　　(2) Strengthen employee training and education, with weekly practice and two exercises per month. Regular accident drills are also conducted to enhance employees’ safety awareness and emergency response capabilities. 　　(3) Use scientific methods and existing testing equipment to detect potential leakage risks in a timely manner, and take preventive measures in advance. 　　Manual inspection methods: (1) Judgment based on the sense of smell and hearing of the inspectors. When natural gas leaks, it accumulates quickly in the upper parts of a room because it is lighter than air. The main component of natural gas is methane, which is also lighter than air. **Thiophenol is added during supply to help users detect leaks; at a leakage level of just 1%, users can smell an odor similar to that of rotten eggs. 　　(2) Soap water test. Use a spray bottle to apply soapy water to the area to be inspected, or use a brush to apply it there; observe whether bubbles form to determine if there is a leak. The amount of leakage can be determined based on the time it takes for the bubbles to form and burst. (3) Instrumental testing. Testing is carried out using relatively advanced handheld natural gas detection instruments. 　　Natural gas leak detection: (1) Twelve natural gas leak detectors have been installed in the boiler room, at a height of 5 meters above the ground. The alarm is interlocked with the DCS monitoring system in the boiler control room. 　　(2) When the test value of any natural gas leak detector reaches or exceeds the maximum allowable limit for leaks, the DCS system issues an audible alarm and simultaneously activates the axial flow fans in the boiler room to facilitate ventilation; operators can then locate the source of the leak in a short time by referring to the values displayed on each detector. 　　(3) The selection of materials, design, processing, and installation are all carried out properly. The leakage rate required for natural gas valves is extremely strict; therefore, full-welded valve bodies are used for valves that are buried or are of significant importance. To ensure the sealing performance of pipeline valves, the sealing pair is required to have excellent corrosion resistance, wear resistance, self-lubricating properties, and elasticity. Every year, the workshop replaces components related to leak control, regulation, and measurement, as well as the fittings at their connection points, using high-quality materials such as polytetrafluoroethylene, nylon, nitrile rubber (NBR), and special synthetic rubbers (VITON), **which helps to reduce natural gas leaks. 　　Adhere to strict safety procedures; enhance fire safety management. Eliminate open flames – starting with those who enter the plant, it is strictly prohibited for anyone entering the boiler room to bring any kind of flame. Personnel and vehicles coming in and going out must be carefully registered and monitored. 　　When welding or gas welding operations need to be carried out inside the boiler room, it is necessary to strictly follow the firework operation approval procedures and take all necessary preventive measures. During such work, a dedicated safety officer from the workshop and the senior management should be present to supervise the operations. It is prohibited to store any flammable materials or miscellaneous items in the boiler room. 　　An explosion-proof door and a rupture disc should be installed on the flue behind the gas boiler (the location of the explosion-proof door and rupture disc should facilitate pressure release; when explosive gases could pose a threat to the safety of operators, a pressure release guide tube should be installed on the explosion-proof door). 　　Boiler combustion adjustment and monitoring during operation: Before starting the boiler (especially when ignition fails or restart is required after automatic shutdown), it is necessary to purge the furnace and flue pipes in accordance with the operating procedures. When adjusting the boiler’s combustion, it should be done slowly to prevent natural gas from leaking into the furnace and flue pipes in case the boiler shuts down. While the boiler is running, the operator must pay close attention to prevent natural gas leaks and automatic shutdown of the burners. 　　Ensure that the fire extinguishing and cooling system (fire protection system) is in good condition. Gas boilers may experience gas leaks due to explosions or other accidents, and even before the gas concentration reaches the lower limit for explosion, they still require protection from a water spray fire extinguishing system. By utilizing the mixing and dilution effect of water spray to reduce the concentration of gas, a fire prevention effect can be achieved. 　　Fire water pipes and fire hydrants must be in good condition, especially during the cold winter months, to prevent the pipes from freezing. 　　Gas composition control technology (nitrogen purging): In addition to purging the natural gas pipelines with nitrogen as required before starting heating by supplying natural gas and after stopping heating by shutting off the natural gas supply, it is also necessary to purge certain sections of the pipelines with nitrogen during operation when electrical welding must be used to address natural gas leaks, in order to ensure safety during the maintenance work. 　　Emergency response to natural gas leaks in gas boiler rooms: Basic procedures for dealing with identified natural gas leak locations. Leaks in outdoor gas pipelines. Immediately notify the gas company’s pressure regulation station to cut off the gas supply, and report to the company’s safety and production departments to take action in accordance with the emergency plan for natural gas leaks. 　　In the event of a leak in indoor gas pipelines, immediately shut down the boiler urgently, close the main gas valve in the boiler room, inform the gas company to adjust the gas supply pressure, and report the situation to the company’s safety and production departments; then take action in accordance with the emergency plan for natural gas leaks. 　　Boiler body leakage a. Emergency shutdown (press the emergency stop button). 　　b. Close the main natural gas valve for that boiler to cut off the gas supply. 　　c. Handle it in accordance with the emergency plan for natural gas leaks. 　　Burner leakage: Immediately shut down the boiler on an emergency basis, close the main gas valve for that boiler, and report the incident to the company’s safety and production departments. Follow the emergency response plan for natural gas leaks, and assign relevant technical personnel to carry out repairs. 　　Leakages in components such as controls, regulators, and meters, as well as at their connection points. 　　Immediately shut down the boiler on an emergency basis, close the main gas valve of that boiler, replace the control, regulating, and measuring components, and reseal any leaking connections. 　　Points to note when dealing with natural gas leaks: Handle the situation in strict accordance with the relevant regulations and procedures for natural gas leaks in the boiler room. 　　Contact the relevant departments of the gas company and heating company in a timely manner. If it is necessary to cut off the natural gas supply, do so; if natural gas replacement is required, carry it out in accordance with the regulations; if procedures for working with flammable materials are needed, follow those procedures; and if professional teams are required for repairs, assign qualified professionals to carry out the work. 　　For various possible leakage incidents, relevant handling plans and emergency response plans should be prepared, and drills for these emergency response plans must be conducted. 　　Ensure an adequate stock of materials specifically designed for dealing with leaks, emergency firefighting equipment, testing tools, etc. 　　To handle leaks, a dedicated safety officer from the workshop must be assigned to oversee the task on site, and relevant personnel must be briefed on the necessary technical procedures. 　　After completion, ensure that all work is done, all materials are used up, and the site is cleaned up; also, fill out the technical documentation carefully.