Indoor fire protection system refers to a facility system installed indoors to extinguish the initial fire of a building. Mainly include indoor fire hydrant system, sprinkler system, water mist fire extinguishing system, foam fire extinguishing system, carbon dioxide fire extinguishing system, halogenated fire extinguishing system , dry powder fire extinguishing system, etc. According to fire statistics, installing an indoor fire protection system is an effective and necessary safety measure.
English name – Indoor Fire Protection System
Purpose – to put out a fire that started in a building
Classification – key words such as foam fire extinguishing system, water mist fire extinguishing system, etc. Indoor fire hydrant, foam fire extinguishing
Application Area – Interior Architecture
Fire hydrant systems and other fire extinguishing systems should be installed in buildings according to the needs of use and the nature of stored items. Pipe networks, fire hydrants, sprinklers, etc. should be arranged in places that are easily accessible and easy to catch fire. For example, fire hydrants are often located near stairwells.
The principles of fire suppression include segmentation, asphyxiation, dilution, cooling and suppression. The extinguishing principles of various extinguishing agents are different. For example, the fire extinguishing principle of water is cooling, dilution and splitting, and the fire extinguishing principle of halogenated is mainly inhibition. However, in order to achieve the purpose of fire extinguishing, the fire must be covered and surrounded by water or other fire extinguishing agents, so the fire extinguishing agent sprayed by the fire extinguishing system should have a certain pressure and flow.
Indoor fire hydrant system
 Indoor hydrant Water supply system is generally used to extinguish the initial fire in buildings, and the fire extinguishing mainly relies on the outdoor fire-fighting water supply system. For buildings with a height of more than 24 meters, it is extremely difficult to use ordinary fire trucks to put out fires. Therefore, the indoor fire hydrant water supply system should have the ability to extinguish fire.
Indoor fire hydrant boxes are generally equipped with water guns, water pipes, etc. In order to extinguish the initial fire, the flow of water guns is generally based on the simultaneous discharge of two water guns, and the average water consumption is about 5 liters per second for each water gun. The indoor fire-fighting water consumption of high-rise buildings is generally calculated based on the outdoor fire-fighting water consumption; the indoor fire-fighting water consumption of high-rise public buildings above 50 meters should be greater than the outdoor fire-fighting water consumption.
Automatic Sprinkler System
A stationary automatic fire extinguishing equipment. In the event of a fire, the sprinkler under the ceiling is heated to a certain temperature (generally 72°C, and 141°C in high-temperature places), and the sprinkler will automatically extinguish the fire. There are two types of nozzles: closed type and open type: ① Closed type nozzle. When the room temperature rises to a certain temperature, the closed head controller responds (eg fusible alloy melts or glassball valve exploded), open the nozzle seal cover, and spray water to put out the fire. ②Open the nozzle. The sprinkler outlet is open. The water spray is controlled by a control valve installed on the pipe. When a fire occurs, the control valve is automatically opened, and the sprinklers installed on the system sprinkle water together to extinguish the fire, so it is also called for the flood system. Closed sprinklers are used in general buildings; open sprinklers should be used on the upper part of theater stages, studios, and warehouses where flammable materials are stacked.
Water (moist) fire extinguishing system
To fight electrical fires, oil fires, etc., a fixed water mist fire extinguishing system can be used. When a fire occurs water mist is sprayed by fire detectors or manually controlled water mist nozzles, which play the role of cooling, suffocating and emulsifying oil to control and extinguish the fire.
Foam Fire Extinguishing System
Foam extinguishing agents are primarily used to fight oil fires such as petroleum and petroleum products. The fire extinguishing principle is: the foam completely covers the surface of the combustion liquid, so that the burning material cannot contact the air required for combustion; the water wrapped in the foam can also cool the surface of the oil. Commonly used foams are air foam and chemical foam. Compared with chemical foam, air foam is simpler to operate, easier to manage, faster to extinguish fires, and has lower equipment cost, and has gradually replaced chemical foam. Air foam systems are available in both stationary and mobile.
Carbon Dioxide Fire Extinguishing System
CO2 is usually pressed into a high pressure vessel under high pressure, while Liquid reservoir that is released from the container in the event of a fire and evaporates and burns Material. Carbon dioxide gas reduces the concentration of oxygen in the air, suffocating and extinguishing fires, and the absorbed heat of vaporization also acts as a coolant and Extinguishing agent. Because of the fast fire extinguishing speed, no corrosion of metal, good insulation performance and no trace after fire extinguishing, the system is suitable for closed rooms such as bookstores, underground garages, transformer rooms, and communication rooms. The system can be divided into two types: stationary and mobile.
Halogenated Fire Extinguishing System
The fire extinguishing principle of halogenated fire extinguishing agent is mainly for Combustion reaction acts as a chemical inhibitor, and is a low-toxicity and high-efficiency fire extinguishing agent. In addition to the stable physical and chemical properties of carbon dioxide fire extinguishing system, the system also has the advantages of low storage pressure and high fire extinguishing efficiency. The halogenated fire extinguishing system is set up and activated in the same way as the carbon dioxide fire extinguishing system, and is suitable for exactly the same fire protection objects.
Dry Powder Fire Extinguishing System
The crystals of dry powder are destroyed by the flame, forming new chemicals to suffocate the fire. At the same time, the dry powder absorbs a lot of heat during the decomposition process, so that the temperature of the fire area drops rapidly, which can reduce the gasification speed of liquid fuel and liquefied gas, thereby controlling the fire. Therefore, dry powder fire extinguishing agents are particularly suitable for fighting fires caused by liquid fuels and liquefied gases. Dry chemical fire suppression systems can be activated by using Fire detectors can be activated automatically or manually. with CO2 fire extinguishing comparison, the disadvantages of dry powder fire extinguishing are high equipment cost and large aftermath work after fire extinguishing.
Current Situation and Deficiency of Indoor Fire Protection System of Multi-storey Buildings in Hong Kong
Although the newly revised《code for design of fire buildings》added the  automatic sprinkler system.However, the indoor fire extinguishing system of multi-storey buildings in Hong Kong have still installed indoor fire hydrants mainly. Practice has proved that indoor hydrant systems are unlikely to be used effectively. When a fire occurs, firefighters often use the method of connecting the water pipes of the fire truck to send the water in the fire truck into the room for use, or use the fire truck to water the fire part outdoors. This will not reflect the significance of indoor fire hydrant settings. The main reasons are as follows: First, under the realistic conditions that the current national fire awareness is generally not high and the basic knowledge of fire fighting skills and fire equipment operation is lacking, it is impossible for ordinary people to effectively use indoor fire hydrant system for putting out fires in the event of a fire. Therefore, indoor hydrant systems ultimately require highly trained firefighters to use. However, 1. Under the circumstance that the current national fire awareness is generally not high, and the basic knowledge of fire fighting skills and fire fighting equipment operation is lacking, it is impossible for ordinary people to effectively use the indoor fire hydrant system to extinguish fire. Put out fire in fire. Therefore, indoor hydrant systems ultimately require highly trained firefighters to use. However, in the event of a fire, the unit personnel who are familiar with the indoor fire hydrant are not necessarily on site, and firefighters are generally unfamiliar with the internal system, so it is difficult to quickly and effectively use indoor fire hydrants to put out fires. Second, the investigation found that most of the indoor fire hydrant systems were poorly maintained, or the valves could not be opened due to rust, or the water pipes were lost. , it cannot be used in an emergency. Third, from a safety standpoint, firefighters do not need to venture into buildings to use indoor hydrants to fight fires when an external water source can be used, especially if no one is trapped in the fire.
In addition, it is known that indoor hydrant water supply systems in multi-storey buildings are mainly used to extinguish fires within the first 10 minutes. But over time, many of the historical conditions that made the Construction Regulations changed. With the development of the economy and the improvement of people’s living conditions, the decoration standards of residences, offices and consumer places have been greatly improved, which has increased the fire load of buildings, and the corresponding fire danger and fire spread speed have also been greatly improved. Increase; Extent of fire extinguishing is extremely high. A low indoor hydrant system can easily delay valuable firefighting time in the early stages of a fire, allowing the fire to spread.
The advantages and necessity of setting up a sprinkler system
The advantage of a sprinkler system is that it does not require personnel to operate the fire, and the duty personnel only need to be in the fire control room. Monitor the situation of the whole building to achieve early detection, early reporting, and early rescue. The fire extinguishing success rate is high, especially the control of the initial fire is extremely effective and reliable. According to foreign data, the success rate of water spraying system is over 90%. Taking the United States as an example, in the 45 years from 1925 to 1969, a total of 81,425 fires occurred in buildings where the system was installed, and the success rate of extinguishing and controlling fires reached 96.2%. Another example is Australia and New Zealand. In the decades from 1886 to 1968, a total of 5,734 fires occurred in buildings where the system was installed, with a success rate of 99.8%. China also has many successful examples. For example, four fires occurred in the Xiamen Textile Factory built in 1958, all of which were automatically activated by the sprinklers. The automatic sprinkler system has become an internationally recognized active fixed firefighting facility that can be widely used due to its strong purpose, direct facing to the fire point, high efficiency, and less water damage. In the United States, sprinkler systems are not only commonly used in high-rise buildings, public buildings, factories, and warehouses, but have also grown to install such systems in family homes.
From an economic point of view. Our sprinkling system has more than 40 years of practical experience. We have extensive experience with product matching, all degrees of automation, operations, etc.; Mass production and use, localization increased resulting in water spray The relative price of fire suppression systems has dropped significantly. According to statistics, the cost of installing fire extinguishing systems in my country generally accounts for 1-3% of the total project investment. Compared with the indoor hydrant system, the cost is not much higher, while the success rate of fire extinguishing is increased several times. Fully meet the requirements of economic interests.