Scope of Application of Heptafluoropropane Fire Extinguishers and Key Points for Use in Enclosed Spaces

　　1. Scope of Application of Heptafluoropropane Fire Extinguishers
　　Heptafluoropropane fire extinguishers are efficient and environmentally friendly fire-fighting devices suitable for various fire scenarios. Specifically, they can be used to extinguish the following types of fires:
　　1. Class A fires: such as initial fires involving solid materials like paper, wood, and cloth. Heptafluoropropane fire extinguishers can quickly suppress the fire and prevent its spread.
　　2. Class B fires: such as fires involving flammable liquids and gases. Since heptafluoropropane is non-conductive, it is also suitable for extinguishing fires involving energized equipment, such as electrical devices and precision instruments.
　　3. Class C fires: gas fires caused by leaks of flammable gases like hydrogen and acetylene. Heptafluoropropane fire extinguishers can rapidly reduce the temperature at the fire scene and dilute the oxygen concentration to achieve fire suppression.
　　2. Usage Requirements of Heptafluoropropane Fire Extinguishing Systems in Enclosed Spaces
　　Heptafluoropropane fire extinguishing systems play an important role in enclosed spaces, but the following requirements must be met when using them:
　　1. Airtightness: To ensure the effectiveness of fire extinguishing, the space using the heptafluoropropane fire extinguishing system must have good airtightness. The fire resistance rating of the protective area's enclosure structures and doors/windows should not be lower than the specified values, and the allowable pressure resistance of the enclosure structures must comply with relevant standards.
　　2. Pressure relief vent setting: When using the heptafluoropropane fire extinguishing system in enclosed spaces, pressure relief vents must be installed. The vents should be located above two-thirds of the net height of the protected area to ensure timely pressure release during fire extinguishing, preventing dangerous overpressure inside the space.
　　3. Ventilation and air exchange: After extinguishing the fire, the enclosed space should be ventilated to ensure safe entry of personnel. Especially for underground protected areas and above-ground protected areas without windows or with fixed window sashes, mechanical exhaust devices should be installed. Exhaust outlets should be located at the lower part of the protected area and directly vented outdoors.
　　3. Pressure Bearing Standards for Enclosed Spaces in Heptafluoropropane Fire Extinguishing Systems
　　Regarding the pressure bearing capacity of enclosed spaces in heptafluoropropane fire extinguishing systems, the following standards generally need to be met:
　　1. Allowable internal pressure resistance of enclosure structures: According to relevant regulations, the allowable internal pressure resistance of enclosure structures in enclosed spaces using heptafluoropropane fire extinguishing systems should not be less than 1200 Pa. This standard ensures the stability and safety of the space during the fire extinguishing process.
　　2. Setting of pressure relief vents and pressure control: As mentioned earlier, the setting of pressure relief vents is crucial for controlling the pressure inside enclosed spaces. By properly setting pressure relief vents, the pressure inside the space during the release of heptafluoropropane extinguishing agent can be effectively controlled, thereby avoiding potential hazardous situations.
　　In summary, heptafluoropropane fire extinguishers have a wide range of applications, especially in enclosed spaces where strict compliance with relevant requirements and standards is necessary. By understanding and mastering these key points, we can better utilize heptafluoropropane fire extinguishers for fire suppression, ensuring the safety of personnel and property.