Fire water consumption The total fire water consumption of a building should be the sum of indoor and outdoor fire water consumption. The amount of water used for indoor fire- fighting should be the sum of the amount of water needed for fire extinguishing system, such as hydrant, automatic sprinkling, foam and other fire extinguishing systems set indoors in civil buildings and factory buildings. That is, when the indoor fire hydrant system, automatic sprinkler system, water spray fire extinguishing system, foam fire extinguishing system or fixed fire foam extinguishing system are installed at the same time, the indoor fire water consumption should be calculated according to the sum of the water consumption of the system mentioned above. When the fire fighting system needs to be opened at the same time, the amount of indoor fire hydrant can be reduced by 50%, but it should not be small.At 10L/s. When the building is equipped with automatic sprinkler system, water spray fire extinguishing system, foam fire extinguishing system or fixed fire extinguishing system, or more than two kinds of automatic fire extinguishing systems, when the height of buildings is not more than 50m and the design flow of indoor hydrant exceeds 20L/s, the design flow of indoor hydrant can be reduced by 5L/s according to the table 3.5.2 of this specification.The design flow of indoor hydrant can be reduced by 50%, but it should not be less than 10L/s. The outdoor fire water consumption of liquid storage tanks (areas) of Class A, B and C shall be calculated according to the sum of fire fighting water consumption and cooling water consumption.