With the development of China's national economy, social progress and the improvement of people’s living standards, clean rooms have been widely used in various industries such as electronics, biopharmaceuticals, and precision instrument manufacturing. Because of the clean room’s temperature, relative humidity and cleanliness The great advantage of the company, its importance is increasingly recognized and accepted by people. How to prevent fire accidents in clean rooms, we believe that the key is to close the source of building fire protection design to prevent the occurrence of congenital fire hazards.
一. The basic characteristics of clean room
The so-called clean room refers to the workshop that has special purification requirements for the building in the production process. Its basic characteristics are: Mostly of reinforced concrete structure, the factory building is divided into several small rooms;It is often in a closed state, with few windows and doors;The equipment in the factory is expensive, afraid of high temperature and avoiding water;Inside the factory The staff is small, which is not conducive to the detection of the fire and the treatment of the initial fire; The internal structure is complicated and the passage is tortuous.
二. Fire characteristics of clean room
1. Smoke heat accumulates and spreads in many ways.
The clean room is generally airtight with few doors and windows. When a fire occurs, the heat of the flue gas is not easy to escape, causing the flue gas to stagnate and the heat to increase sharply. In addition, the ventilation pipes, electrical wiring sleeves, and technical interlayers in the factory are in collusion with each other. It is easy to cause the heat and smoke to spread quickly to other rooms.
2. It is difficult for personnel to escape.
Due to the technical requirements, the internal separation of the clean room is complicated, the passage is narrow, the safety exit is small, the depth is long, and it is easy to lose its direction after a fire. In addition, there are few staff. The initial fire disaster is discovered in time, and it is difficult to get out when the fireworks attack. .
3. The smoke is very toxic.
Some high-molecular synthetic materials are used in interior decoration. These materials will produce a lot of dense smoke and toxic gas when they are burned, which poses a great threat to personnel escape and firefighting.
4. Large losses.
There are often a lot of extremely sophisticated and expensive equipment in the clean room, and the construction investment is large. Once a fire occurs, the economic loss will be huge.
三．The basic principles to be grasped in the fire protection design of clean room buildings
According to the characteristics of the clean room and its fire characteristics, in order to ensure the safety of people's lives and property, minimize the loss in fire, and facilitate the evacuation and rescue of personnel, we should follow the following principles in building fire protection design.
1. Fire resistance rating and fire zone
From many clean room fire examples, it is not difficult to find that it is necessary to strictly control the fire resistance level of the building. The fire resistance level of the plant is set as one or two during the design, so that the fire resistance of the building components is comparable to that of the Class A and B production plants. Adaptation, thereby greatly reducing the possibility of fire.
2. Safe evacuation
In view of the characteristics of the clean room itself, we should fully consider the requirements for safe evacuation of personnel in our design, comprehensively analyze factors such as evacuation flow, evacuation routes, evacuation distance, etc., through scientific calculations, select the best evacuation route, and reasonably arrange safe exits and evacuation The passage establishes a safe evacuation structure system, so that it can satisfy the purification route from the production site to the safe exit without tortuous.
3. Heating, ventilation and smoke prevention
Ventilation and air conditioning systems are usually arranged in clean rooms. The purpose is to ensure the cleanliness of the air in the clean rooms, but at the same time it also brings a potential fire hazard. If the ventilation and air conditioning system is not properly fired, it will cause fireworks. It spreads everywhere through the ventilation and air conditioning pipe network, causing the fire to expand.
At the same time, since the clean room doors are relatively closed, it is not conducive to natural smoke exhaust. An accident smoke exhaust system should be installed in the factory building, and a mechanical smoke exhaust system with positive pressure air supply should be installed on the evacuation corridor to ensure that the smoke can be quickly discharged into the room without intruding into the evacuation corridor, so as to ensure that personnel can evacuate the fire site in time and safely .
4. Fire fighting facilities
The clean room is equipped with fire-fighting water supply, fire-extinguishing equipment and automatic fire alarm system in accordance with the requirements of the regulations. The main purpose is to detect fires in time and eliminate fire accidents in the initial stage. Since the clean room has a technical interlayer and a lower interlayer for the return air space, we should consider it when arranging the alarm probe, which is more conducive to timely detection of fire.
5. Renovation project
In the clean room decoration, we must pay attention to the combustion performance of the decoration materials and minimize the use of some polymer synthetic materials to avoid a large amount of smoke when a fire occurs, which is not conducive to personnel escape. In addition, strict requirements should be imposed on the pipe penetration of electrical circuits, and steel pipes should be used where possible to ensure that electrical circuits do not become a way for fire to spread.