Design characteristics of fire weak current system

Design features of weak current system for fire protection of super high-rise buildings

according to the regulations, the fire protection system design of buildings with a building height of 24 meters and below in China shall be implemented in accordance with the national standard code for fire protection design of buildings, buildings with a height of 24 ~ 100 meters shall be implemented in accordance with the national standard code for fire protection design of high rise civil buildings, and 80% of underground industrial or civil buildings shall be implemented in accordance with the code for fire protection design of civil air defense engineering. The national standard is a mandatory technical regulation and a common ruler that restricts the owner, the design unit, the construction unit and the acceptance unit. There is no corresponding national standard for super high-rise buildings. In actual work, we can only refer to the relevant national standards and international standards. According to the intention of the local fire department, we can only see under the same experimental conditions. In the spirit of safety first, we should try to complete the design work carefully and thoroughly

2 ﹐ the layout standard of fire detectors is high

in general super high-rise buildings, except for the top floor, the roof of each floor is flat (that is, the slope of the top floor is zero), and the floor height is not more than 6 meters. Under this condition, the protection area of smoke detectors in general buildings is generally 60 square meters, and the protection radius is 5.8 meters. However, for super high-rise buildings, the fire department often requires to improve the standard, for example, the protection area is required to be 40 ~ 50 square meters, and the protection radius is strictly controlled, which is determined according to the rectangular length width ratio formed by the detector position. Obviously, the detector layout is more economical with a nearly square layout. Temperature detectors are set in basements, kitchens and places where smoking is allowed. Under flat roof conditions, the protection area is 20 square meters and the protection radius is 3.6 meters. It should be noted that the problem often lies in the corners of the building plane, and the protection radius of the detector cannot meet the audit requirements. Such problems that can be accommodated in general buildings should be strictly implemented in super high-rise buildings. In addition, in the power transformation and distribution room, generator room, belt conveyor and cable tray, in addition to the gas fire extinguishing device (generally built by the owner after Civil Engineering), cable smoke detectors should also be considered

3. Alarm means

in addition to smoke detectors, temperature sensors, manual alarm buttons, fire hydrant buttons, etc., combustible gas detectors should be added to garages and kitchens in super high-rise buildings. In all important machine rooms (attended), especially in the fire control room on the first floor, 119 special fire fighting equipment should be set, such as some machines, handles on instruments, handwheels and sanitary equipment, and the decorative surfaces of some parts of the experimental machine on the food experimental machine, which are directly connected with the 119 exchange equipment of the Municipal Bureau. As for the alarm floor lights, generally all are set, and the alarm bell or buzzer, because it creates artificial panic and confusion, under the condition of emergency broadcasting, Mostly not

4 ﹐ alarm detector installation site

detectors should be set in all rooms with an area of more than 5 square meters in the super high rise, even in the toilet. In addition, the staircase is a fire escape passage, and detectors should be set. The electric shaft, regardless of its size, must be set layer by layer because of its high possibility of fire and important role. The setting radius of the manual alarm is 30 meters walking distance, which is generally located near the escape exits such as staircases and exits, so that personnel can easily alarm when fleeing the fire

5. Fire fighting arrangement of refuge floor

the setting of refuge floor is a special emergency measure for super high-rise buildings. The anchor and anchor chain, the main parts used in the shipyard, must be tested. It is used for personnel to stay temporarily when avoiding fire, so as to make up for the lack of fire-fighting capacity brought by the super high-rise to the fire-fighting equipment (especially in China). Generally, one refuge floor is set every 50 meters, and two refuge floors are set at the height of 100 ~ 200 meters. Generally, there is no daily office or living place in the refuge floor, that is, its building space is only used for disaster relief and emergency. However, in order to solve the practical problems of super high-rise buildings and meet the needs of fire fighting, some equipment rooms, such as smoke control positive pressure fans, smoke exhaust fans, air conditioning units, fresh air units, etc., are usually set up on the premise of ensuring the needs of personnel to avoid fire, and the positive pressure air inlet system of the refuge floor is required to be set independently, with an air supply volume of not less than 30 cubic meters per hour. The smoke exhaust fan and positive pressure fan of the refuge floor shall work at the same time in case of fire, and the smoke exhaust outlet and air inlet shall not be arranged adjacent

the smoke detector layout condition of the refuge floor is also that the protection radius is not greater than 5.8 meters (if a temperature detector is set, the protection area is not greater than 20 square meters), and the manual alarm button is also set near the entrance and exit. At least one manual alarm is set in each fire compartment, and the responsible radius of each manual alarm is not greater than 30 meters, which is generally installed on the wall about 1.4 meters away from the ground. Most super high-rise buildings are in the shape of towers, with at least one fire compartment on each floor, but usually there is mostly one fire compartment on each floor

in order to ensure smooth communication in case of emergency, a special extension or jack for fire fighting shall be set every 20 meters in the refuge floor