The fire-extinguishing principle and application scope of IG541 mixed gas firefighting

　　IG541 is a type of gaseous fire suppression system commonly used in large equipment rooms, precision instrument facilities, libraries, or areas frequented by people—thanks to its product characteristics: non-toxic, non-polluting, and harmless, making it highly popular in the market.

　　IG541 is a hybrid gas fire suppressant composed of 52% nitrogen, 40% argon, and 8% carbon dioxide. It is a colorless, odorless, non-toxic, and non-conductive gas with an ozone depletion potential (ODP) of 0 and a global warming potential (GWP) of 0. Additionally, it has a very short atmospheric lifetime, making it an environmentally friendly, green-type fire suppressant.

　　The IG-541 mixed-gas automatic fire suppression system primarily consists of: a gas fire suppression alarm and control system, a fire detection system, fire-suppressant storage cylinders, container valves, selection valves, pressure-reducing devices, check valves, air circuit control valves, pressure switches, nozzles, piping, and other key components. It can be configured as either a standalone unit system or a distributed system, enabling fire protection for one or multiple zones.

　　1: Fire Extinguishing Principles

　　The IG-541 fire suppression system primarily relies on physical extinguishing methods, specifically by suffocating and reducing the oxygen concentration in the enclosed space.

　　The IG541 mixed gas works by releasing carbon dioxide, which reduces the oxygen concentration below the level needed to sustain combustion, thereby extinguishing the fire. Typically, the air in the protected area contains 21% oxygen and less than 1% IG541.

　　When oxygen levels in the protected area drop below 15%, most combustible materials will cease to burn. The inert gas mixture can reduce oxygen levels in the protected zone to 12.5% while simultaneously increasing IG541 to 4%. Increasing the proportion of IG541 not only accelerates human breathing rates but also enhances the body's ability to absorb oxygen, effectively compensating for the lower oxygen concentration in the surrounding atmosphere. Furthermore, when the fire suppression system is designed with a maximum IG541 concentration of no more than 43%, it remains safe and harmless to humans.

　　2: How It Works

　　The IG541 fire suppression system offers three options for users to choose from: automatic fire suppression, emergency electrical manual activation, and on-site mechanical activation for fire extinguishing.

　　When any detector within the protected area triggers an alarm, the fire signal is transmitted to the fire alarm control panel, activating the audible and visual alarms installed in the protected area's control room. All personnel inside the protected area must immediately evacuate.

　　When two detectors in a protected area simultaneously trigger alarms, the outdoor audio-visual alarm system activates, and the fire alarm control panel sends联动 signals to coordinate the operation of fans, fire dampers, air conditioning units, and other equipment. Meanwhile, the fire alarm control panel automatically initiates a pre-set 30-second delay before activating the gas fire suppression system via the gas extinguishing controller.

　　When the delay time expires, the gas fire suppression controller sends a signal to release the IG541 mixed gas, activating the solenoid valve on the IG541 gas cylinder. This, in turn, uses nitrogen gas to open the selection valve corresponding to the protected zone, which then allows the container valve on the IG541 gas cylinder to release the IG541 mixed gas for fire suppression. Once the gas fire suppression controller receives the gas-release signal from the pressure switch installed on the main pipeline, it illuminates the gas-spray indicator light, alerting personnel outside the protected area not to enter. The IG541 mixed gas will completely flood and fill the entire protected zone within the specified time.

　　Throughout the IG541 mixed-gas fire suppression process, the gas fire control panel transmits the control panel fault signal and the gas release signal to the fire alarm control panel.

　　3: Scope of Application

　　The IG-541 mixed-gas fire suppression system's extinguishing method is suitable for total flooding fire suppression systems.

　　The IG-541 fire suppression system is primarily suitable for use in electronic computer rooms, telecommunications centers, electrical distribution rooms, oil-immersed transformers, standby generator rooms, libraries, archives, museums, and areas like ticket and cultural heritage storage facilities—places where people frequently work. It can effectively extinguish electrical fires, liquid fires, or fires involving combustible solids that may melt, as well as solid-surface fires and gas fires where the gas supply can be shut off before ignition occurs. However, it is not appropriate for Class D fires involving reactive metals.