【Cause】After the data center gas fire suppression system discharges, the extinguishing agent concentration is insufficient, failing to effectively extinguish the fire, and the HF decomposition products corrode precision equipment.
Gaseous fire suppression systems are suitable for data center electrical rooms, archives, museums, and other locations where water-based extinguishing is not advisable. They offer advantages such as leaving no residue, being non-conductive, and not damaging precision equipment. GB 50370-2005 "Code for Design of Gas Fire Extinguishing Systems" is the core design basis, covering design requirements for common systems such as heptafluoropropane (FM200), IG541 (Inergen), and high-pressure CO2. GB 50371-2006 specifies construction and acceptance requirements.
Heptafluoropropane (FM200) is the most commonly used, with a design concentration of 8% to 10%. It offers high extinguishing efficiency and low toxicity, but has a GWP of 3350, making it a greenhouse gas. IG541 is environmentally friendly, composed of 52% nitrogen, 40% argon, and 8% CO2, with a design concentration of 37.5% to 42.8%, but requires a large number of cylinders and has high costs. High-pressure CO2 has a design concentration of 34% to 75% and is low in price, but high concentrations are lethal to humans and require strict safety measures. Hot aerosol does not require pressure vessels but may leave residue.
The system consists of agent storage cylinders, actuator cylinders, selector valves, nozzles, piping, and a control system. The control system includes smoke and heat detectors, control panels, audible and visual alarms, and emergency start/stop buttons. The enclosure of the protected zone should be able to withstand the discharge pressure, and openings should close automatically. For discharge time, heptafluoropropane should discharge over 95% within 10 seconds. Soaking time should be at least 10 minutes for solid fires and at least 5 minutes for liquid fires.
Safety measures require a 30 to 60 second evacuation delay before agent discharge. Emergency stop buttons should be installed both inside and outside the protected zone. Fire dampers should close automatically before discharge. Access control should unlock automatically before discharge. Oxygen concentration monitoring ensures personnel safety when entering after suppression. The cylinder room should have a fire resistance rating of at least Class II, be provided with explosion venting, and maintain an ambient temperature of -10 to 50°C. Piping should be secured with supports and hangers, and airtightness testing should be conducted at 1.15 times the working pressure.
Monthly checks include cylinder pressure gauges and system power supply. Quarterly checks include pipe connections and nozzles. Semi-annual weighing to detect agent loss; recharge if loss exceeds 5%. Annual full linkage testing. Five-year hydrostatic testing of cylinder assemblies. Heptafluoropropane decomposes above 350°C to produce HF (hydrogen fluoride), which is highly corrosive. The key to controlling HF is ensuring complete discharge within 10 seconds to extinguish the fire quickly and reduce fire scene temperatures.
The application of gaseous fire suppression systems in hotel data rooms and electrical rooms requires particular attention. The data room is the information hub of hotel operations, and the reliability of the gaseous fire suppression system directly affects business continuity. System design should fully consider the airtightness of the protected zone, including all potential leakage points such as HVAC duct penetrations, cable tray openings, and door gaps, all of which must be sealed. Post-suppression recovery is equally important; it is recommended to provide a post-suppression forced ventilation system that automatically starts exhaust within 10 minutes after fire confirmation and suppression to remove the agent and decomposition products. Maintenance of the gaseous fire suppression system should be carried out by professionally trained personnel. The temperature and humidity of the cylinder room should be controlled within the specified range, and unauthorized personnel must be prohibited from entering. During system repair or recharging, a backup plan should be in place to ensure uninterrupted protection of the protected zone.
Full lifecycle management of gaseous fire suppression systems requires focus on the following aspects. During the design phase, the agent quantity should be accurately calculated based on the actual dimensions and openings of the protected zone, with corrections for altitude and temperature effects on agent concentration. During construction, piping installation and nozzle positioning should strictly follow design drawings and code requirements, and airtightness testing should be conducted after piping installation to ensure no leakage. During acceptance, comprehensive functional testing should be conducted, including detector linkage testing, delay start testing, discharge simulation testing, and audible/visual alarm testing. During operation and maintenance, a regular inspection and testing regime should be established: cylinder pressure checked monthly, agent weight checked semi-annually, and system linkage function tested annually. Periodic hydrostatic testing of cylinders should be conducted every five years, and cylinders that fail the test should be replaced immediately. Spare parts for the gaseous fire suppression system, including seals, fusible links, and actuator cylinders, should be kept sufficient. The airtightness of the protected zone should be checked annually, particularly at HVAC duct wall penetrations and cable tray openings where new leakage points are prone to develop. Operation training for the gaseous fire suppression system should cover relevant personnel from the hotel engineering and security departments, with at least one emergency operation drill per year to ensure correct operation of the system in emergency situations.
Full lifecycle management of gaseous fire suppression systems requires focus on the following aspects. During the design phase, the agent quantity should be accurately calculated based on the actual dimensions and openings of the protected zone, with corrections for altitude and temperature effects on agent concentration. During construction, piping installation and nozzle positioning should strictly follow design drawings and code requirements, and airtightness testing should be conducted after piping installation to ensure no leakage. During acceptance, comprehensive functional testing should be conducted, including detector linkage testing, delay start testing, discharge simulation testing, and audible/visual alarm testing. During operation and maintenance, a regular inspection and testing regime should be established: cylinder pressure checked monthly, agent weight checked semi-annually, and system linkage function tested annually. Periodic hydrostatic testing of cylinders should be conducted every five years, and cylinders that fail the test should be replaced immediately. Spare parts for the gaseous fire suppression system, including seals, fusible links, and actuator cylinders, should be kept sufficient. The airtightness of the protected zone should be checked annually, particularly at HVAC duct wall penetrations and cable tray openings where new leakage points are prone to develop. Operation training for the gaseous fire suppression system should cover relevant personnel from the hotel engineering and security departments, with at least one emergency operation drill per year to ensure correct operation of the system in emergency situations. Design documents for the gaseous fire suppression system should include the protected zone floor plan, system schematic diagram, piping routing diagram, and cylinder room layout. Changes during construction should be confirmed by the design unit and drawings updated accordingly. The cylinder room should be provided with conspicuous warning signs and operating procedures, and unauthorized personnel must not enter. Recovery operations after system activation should be performed by trained professionals: first confirm the fire is fully extinguished, then start the forced ventilation system to remove the agent and decomposition products, and only after ventilation is complete may personnel enter the protected zone to inspect equipment status. Agent cylinders should be replaced or recharged promptly after activation, and the cylinder validity period and hydrostatic test date should be checked before recharging. The annual inspection report for the gaseous fire suppression system should include system appearance inspection, functional test results, and cylinder status inspection records.
The design documents for a gas fire extinguishing system shall include the protected area floor plan, system schematic diagram, pipe routing diagram and cylinder room layout diagram. Changes during construction shall be confirmed by the design unit and the drawings updated. The cylinder room shall be provided with conspicuous warning signs and operating procedures; unauthorized personnel shall not enter. Restoration operations after the gas fire extinguishing system is activated shall be carried out by trained professionals: first confirm that the fire has been completely extinguished, then start the forced ventilation system to exhaust the extinguishing agent and decomposition products. After a extinguishing agent cylinder has operated, it shall be replaced or refilled promptly; before refilling, the cylinder's validity period and hydrostatic test date shall be checked. The annual inspection report of the gas fire extinguishing system shall include the system appearance inspection, function test results and cylinder status inspection records. The transportation and installation of cylinders for the gas fire extinguishing system shall comply with the safety regulations for the transportation and storage of hazardous chemicals. HFC-227ea cylinders shall be transported using dedicated vehicles; cylinders shall be loaded and unloaded using dedicated equipment, handled gently and never thrown. Cylinders in the cylinder room shall be securely fixed to prevent tipping. The piping installation of the gas fire extinguishing system shall comply with the requirements of the safety technical regulations for pressure piping, and the material, specifications and connection methods of the piping shall comply with the design requirements. The environmental adaptability of the gas fire extinguishing system is also a factor to be considered in the design. Under high-temperature conditions, the cylinder pressure of HFC-227ea rises; the temperature of the cylinder room shall not exceed 50°C. Under low-temperature conditions, the cylinder pressure of IG541 decreases; the temperature of the cylinder room shall not be lower than 0°C. The ventilation of the cylinder room shall be determined according to the properties of the extinguishing agent; HFC-227ea is heavier than air and accumulates near the floor after leakage, so the exhaust outlets of the cylinder room shall be located low. The interlock between the gas fire extinguishing system and the air-conditioning system shall be determined at the design stage; the air-conditioning system shall shut down automatically before the gas is discharged. Through standardized installation and construction and strict acceptance management, the installation quality and safety reliability of the gas fire extinguishing system are ensured.
The transportation and installation of cylinders for the gas fire extinguishing system shall comply with the safety regulations for the transportation and storage of hazardous chemicals. HFC-227ea cylinders shall be transported using dedicated vehicles, and the driver shall hold a hazardous goods transportation qualification certificate. Cylinders shall be loaded and unloaded using dedicated equipment, handled gently and never thrown. Cylinders in the cylinder room shall be securely fixed to prevent tipping. The piping installation of the gas fire extinguishing system shall comply with the requirements of the safety technical regulations for pressure piping; the material, specifications and connection methods of the piping shall comply with the design requirements. The environmental adaptability of the gas fire extinguishing system is also a factor to be considered in the design. Under high-temperature conditions, the cylinder pressure of HFC-227ea rises; the temperature of the cylinder room shall not exceed 50°C. Under low-temperature conditions, the cylinder pressure of IG541 decreases; the temperature of the cylinder room shall not be lower than 0°C. The ventilation of the cylinder room shall be determined according to the properties of the extinguishing agent; HFC-227ea is heavier than air and accumulates near the floor after leakage, so the exhaust outlets of the cylinder room shall be located low. The interlock between the gas fire extinguishing system and the air-conditioning system shall be determined at the design stage; the air-conditioning system shall shut down automatically before the gas is discharged to prevent loss of extinguishing agent. Through standardized installation and construction and strict acceptance management, the installation quality and safety reliability of the gas fire extinguishing system are ensured.
The design documents for a gas fire extinguishing system shall include the protected area floor plan, system schematic diagram, pipe routing diagram and cylinder room layout diagram. Construction changes shall be confirmed by the design unit and the drawings updated. The cylinder room shall be provided with conspicuous warning signs and operating procedures; unauthorized personnel shall not enter. After a extinguishing agent cylinder has operated, it shall be replaced or refilled promptly; before refilling, the cylinder's validity period and hydrostatic test date shall be checked. The annual inspection report of the gas fire extinguishing system shall include the system appearance inspection, function test results and cylinder status inspection records. The installation and construction of the gas fire extinguishing system shall be undertaken by professional units with the corresponding qualifications, and the construction process shall be subject to the supervision and inspection of the supervision unit. Through full-life-cycle quality management, the safe and reliable operation of the gas fire extinguishing system is ensured.