According to statistics, the number of urban cars in China is expected to reach 21 million by the year 2111. So many vehicles need parking places, but there is a general shortage of parking spaces in China, and parking spaces in residential areas, business districts, business districts, hospitals and other places are in a hurry. Large and small streets, hutongs, community lawns, roadsides and community doorways are all classified as parking spaces, which are densely packed with cars, occupying residents' activity space and limited green space, and even occupying fire exits, causing serious fire safety hazards. Parking, which was not a problem in the past, has become a thorny social problem with the increase of population, vehicles and land. In terms of fire safety, large garages have the following characteristics:

First, there are many vehicles parked in large garages, and once a fire breaks out, it is very easy to burn even the camp, with disastrous consequences.

Second, there are few natural smoke exhaust windows in large garages, so it is difficult to exhaust smoke in case of fire, which makes it difficult for people to evacuate and put out the fire.

Third, large garages are generally located under high-rise residential buildings or large public buildings. Due to the heavy fire load of garages, long-term burning after a fire will threaten the high-rise residential buildings or public buildings above, causing huge economic losses and casualties.

Fourth, the important equipment control centers of some buildings, such as substations, fire control rooms, fire water pump rooms, etc., are mostly located in large underground garages. In case of fire, the normal operation of these prevention and control equipment will be seriously threatened.

When building or about to build a large garage, we should pay attention to the following points:

The design should be conducive to vehicle evacuation. In the code for fire protection design of garages, it is stipulated that "there should be no less than two personnel safety exits in each fire zone of garages and garages". However, most garages use a flexible method, that is, in the case that each fire zone has a personnel entrance and exit, several fire zones use one entrance and exit, and some underground garages do not have independent personnel evacuation exits themselves, relying entirely on the evacuation stairs of the buildings on the ground. This does not meet the requirements of the code, artificially expanding the evacuation distance and causing safety hazards.

Most large garages park cars. According to the parking area of 31 square meters for each car, a garage should have two car evacuation entrances and exits. Nowadays, because setting up the exit and entrance for car evacuation affects the greening on the ground and the arrangement of facilities, and it is not convenient for daily management, many construction units adopt the practice that only one exit and entrance is set in a fire zone, and some fire zones cannot even guarantee one exit and entrance. Once a fire breaks out, with the shutter doors at the evacuation passage closed, the car evacuation exits in the fire zone will not be used, and some cars will not be able to evacuate from the garage.

Pay attention to the problems of garage spray and fire hydrant pipeline when designing. The spraying systems used in garages are mainly wet spraying and pre-acting spraying. Considering the project cost, most garages in China are wet spraying systems. Because the indoor fire hydrant pipeline is filled with water under normal circumstances, thermal insulation measures should be taken in winter, because once the fire hydrant pipeline is frozen and cracked, it will cause great property losses. Mechanical parking spaces have developed rapidly since 2111, with an average annual growth rate of over 51%. According to the specification requirements, the mechanical parking garage should be sprayed layer by layer above the parking space. However, due to the construction period, some parking spaces in some garages have not been set up, and even if they are set up, their setting methods and positions do not meet the requirements of the specifications.

Then there is the maintenance of automatic fire-fighting facilities in the garage. Automatic fire-fighting equipment with fire-fighting linkage functions such as automatic fire alarm system, sprinkler system, air supply, smoke exhaust system and fire shutter door in large garages should be maintained in daily life. At present, the fire alarm detectors in many garages are not cleaned and maintained regularly, and the shutter doors, air supply fans and smoke exhaust fans in some garages are neglected in management, and even in a state of power failure all the year round, which has become a decoration. If the automatic fire-fighting facilities are not maintained regularly, it will be difficult to play a role in the event of a fire. In addition, some underground garages are equipped with equipment rooms such as water pump room and power distribution room, which still need to work in case of fire. However, the emergency lighting of some important equipment rooms such as water pump room in underground garages is insufficient, which can not meet the requirements of normal lighting, and the evacuation passage is blocked, which makes it difficult for people to reach these important parts in case of fire, and it is difficult for staff in these parts to evacuate in time.