GB 50016-2014（2018）- Provisions of Code for Fire Protection Design of Buildings
4 Category A, B, C liquid and gas tanks (tank farm) and stackyard for combustibles
4.1 General requirements
4.1.1 Combined with the development needs of cities in China, this provision stipulates the arrangement requirements of Category A, B and C liquid tank farm, LPG tank farm, combustible and combustion-supporting gas tank farm, stackyard for combustibles, etc., so as to ensure the safety of cities and residential areas.
The open stackyards for combustibles in this Code includes the stackyards for straw, reed, tobacco leaves, herbs, hemp, bagasse, wood, pulp raw materials, coal, etc. Once a fire happens in these places, it is difficult to extinguish the fire and the harm range is large. In the actual site selection, these places shall be arranged as far as possible in the city and at the windward side with the annual minimum frequency; when there are difficulties, try to choose the windward side with the annual minimum frequency in this area or this unit throughout the year, so as to prevent the fire from harming other buildings or combustibles stacks.
Category A, B and C liquid tanks (tank farm) should be arranged in the zone with low terrain as far as possible. Where they are arranged in the zone with high terrain, security facilities such as strengthening fire dikes or adding additional protective walls should be taken; because of the characteristics of high relative density, large gasification volume and low explosion limit, the LPG tank farm should be as far away as possible from residential areas, industrial enterprises and areas with important public buildings such as theaters, cinemas, gymnasiums, schools and hospitals, and be arranged separately in well-ventilated areas.
In these places specified in this provision, the burning speed is fast with strong radiant heat, and it is difficult to put out the fire. The fire often lasts for a long time, and some places still have explosion danger, which endangers a large range and consumes a large amount of water for saving and cooling. Therefore, the source and guarantee degree of fire water should be fully considered in site selection.
4.1.2 This provision is compulsory. This provision is mainly aimed at Category A liquid with low flash point, which is sensitive to temperature and it is specially necessary to prevent overpressure explosion and fire due to open storage in hot climate in summer.
4.1.3 This provision is compulsory. When liquefied petroleum gas leaks, its gasification volume is large and diffusion range is wide, and it is prone to accumulate and cause serious disasters. In addition to comprehensive consideration in site selection, measures should be taken to avoid and reduce the harm of tank explosion or leakage to surrounding buildings as far as possible.
Setting up the protective walls can prevent leakage and outflow of storage tanks from endangering other buildings. The height of the protective wall is not greater than 1.0m, which has little influence on ventilation and will not accumulate air. The relevant specifications of the United States and the former Soviet Union all have corresponding requirements for setting up protective walls in tank farms. Fire dikes are also set in every LPG tank farm and every storage tank in Japan. Therefore, this provision requires that a protective wall with a height of not less than 1.0m should be set in the LPG tank farm, but the distance between the tank and the protective wall should be considered as half of its length for horizontal tanks and half of its diameter for spherical tanks.
The fire separation distance between LPG tank and surrounding buildings shall meet the relevant requirements of 4.4 of this Code and the current national standard GB 50028 Code for design of city gas engineering.
4.1.4 If the loading and unloading facilities are located in or near the tank area, when the storage tank leaks, vehicles enter or loading and unloading operations are carried out, there is a danger of fire caused by explosion. In the design of these places, partition according to function shall be considered first, and the storage tanks should be arranged separately from their loading and unloading facilities and auxiliary management facilities, so as to take isolation measures and manage.
4.2 Fire separation distance of Category A, B, C liquid tanks (tank farm)
This provision is mainly aimed at Category A, B and C liquid tanks (tank farm) in industrial enterprises and independently built. In order to facilitate the implementation of this Code and the coordination between standards, the arrangement of storage tanks in professional oil depots and the fire separation distance between storage tanks and buildings inside and outside the depots shall meet the requirements of GB 50074 Code for design of oil depot.
4.2.1 This provision is compulsory. This provision specifies the fire separation distance between Category A, B and C liquid tanks and barreled Category B and C liquid stackyards and other buildings
(1) The maximum total capacity of Category A, B and C liquid tanks and barreled Category B and C liquid stackyards is determined according to the capacity of combustible liquid storage affiliated to factories and enterprises and other Category A, B and C liquid tanks and storages.
The fire separation distance specified in Table 4.2.1 is mainly put forward according to fire examples, basically meeting the requirements of fire fighting and some current practical practices. If a 30m3 horizontal oil tank explodes and catches fire, it can shatter the windows and doors with a distance of 15m, and the radiant heat may ignite the combustibles with a distance of 12m. According to the practical experience of fighting oil tanks, when the oil tanks (pools) catch fire, they burn violently and have strong radiant heat. To meet the fire fighting needs, there shall be a safe distance of at least 12~15m away if the small tanks catch fire, and 15~20m in the case of relative large tank.
(2) For a tank farm where Category A, B and C liquids may be stored at the same time, when determining the fire separation distance between tank farms, it is necessary to convert the capacity of different combustible liquids into the capacity of the same type of liquid (which can be converted into Category A, B or C liquids), and then determine it according to those specified in Table 4.2.1 of this Code .
(3) Explanation on the notes in Table 4.2.1.
Note 3: Because the fixed roof tank farm and semi-open stackyard of Category A, B and C liquids and barreled Category B and C liquid stackyard have a great influence on each other with Category A factory buildings (storage)/civil buildings in case of fire, the corresponding fire separation distance shall be increased by 25% on basis of those specified in Table 4.2.1. In case of oil leakage due to boil over or rupture in the above-mentioned storage tanks and stackyard, fire will be caused when encountering ignition sources, so the fire separation distance from open flames or sparking sites is increased by 25% on the basis of the requirements for the building with Class IV fire resistance in this table.
Note 4: The fire separation distance between tank farm with floating roof or liquid tank farm with the flash point over 120℃ shall be decreased by 25% on basis of those specified in Table 4.2.1 relatively small fire hazard, and it should not be decreased as far as possible for high-rise buildings and their podium.
