The design flow of indoor fire hydrants in buildings should not be less than that specified in Table 4-3.

Table 4-3 Design Flow of Indoor Fire Hydrants in Buildings

Note: 1. The design flow of indoor fire hydrants in Class D and E high-rise workshops (warehouses) can be reduced by 11L/s according to this table, and the number of fire water guns used can be reduced by 2 according to this table.

2. When the height of a high-rise civil building does not exceed 51m, the water consumption of indoor fire hydrants exceeds 21L/s, and an automatic sprinkler system is installed, the indoor and outdoor fire water consumption can be reduced by 5L/s according to this table.

3. The design flow of fire water supply for fire hose reels, portable fire hoses and dry fire standpipes in stairwells of multi-storey houses may not be included in the design flow of indoor fire water supply.

Underground buildings mainly refer to houses or places built below the surface for people to live or engage in other activities. They are relatively independent underground buildings under squares, green spaces, roads, railways, parking lots, parks and other land, with the exception of underground rail transit facilities, underground municipal facilities and underground special facilities.

the area of the above-ground building serving the underground building is also included in the underground building area.

underground buildings are shown in figure 4-48 and figure 4-49.

Figure 4-48 Schematic Diagram of Underground Building (I)

Figure 4-49 Schematic Diagram of Underground Building (II)

Calculate the fire-fighting water quantity of multi-storey comprehensive building, take the total building volume and total height, look up the flow in Table 4-3 according to different functions, and select the maximum value as the fire-fighting water quantity.

the fire protection example of the complex building is shown in figure 4-51.

figure 4-51 fire-fighting example of a comprehensive building

in the example of figure 4-51, the fire-fighting water consumption is looked up in table 4-3 according to the total volume v for the four functions of underground garage, business, office and hotel, and the largest one is the fire-fighting water consumption of this comprehensive building.