(1) Division of design units.
The place where the fire extinguisher is deployed refers to the room or part where combustibles are produced, used, and stored and the fire extinguisher is required. Such as paint room, power distribution room, instrument control room, office, laboratory, warehouse, stage, stacking, etc. The calculation unit refers to the division of areas for the convenience of design after considering factors such as fire type, danger level and adjacency in the process of fire extinguisher configuration design. A computing unit can be a place with only one fire extinguisher;It can also contain a plurality of fire extinguisher configuration places, but at this time, the protection area, protection distance and number of fire extinguisher configurations should be considered as a whole.
Obviously, for the fire extinguisher configuration sites that are not adjacent to each other, the configuration design calculation of the fire extinguisher should be carried out separately as a calculation unit. However, for adjacent configuration sites with the same hazard level and fire type, or there is an adjacent configuration site with different hazard level and fire type, it shall be divided according to the following two provisions:
1) If the fire extinguisher is configured in an adjacent place with the same hazard level and fire type, a floor or a fire partition can be used as a calculation unit.
2) The places where the fire extinguisher is configured with different hazard levels or fire types should be used as a calculation unit respectively.
2) Calculation of the area to be protected by the unit.
After dividing the fire extinguisher configuration site, the protection area needs to be calculated. The fire extinguisher configuration place (unit) needs to be calculated with the fire extinguisher protection area, and the provisions are as follows:
1) The construction project is calculated according to the usable area;
2) Open-air stacking of combustibles, Class A, B and C liquid storage tanks, and combustible gas storage tanks are calculated according to the floor area of the stacking and storage tanks.
1) The unit needs to be equipped with the calculation and example of the fire extinguishing level.
1.Calculation formula: q=k1·k2·s u
Where: Q - fire extinguisher configuration place (unit) to be equipped with fire extinguishing level, a or b;
s—the protection area of the fire extinguisher configuration site ( ).
U-A fire extinguisher configuration standard (A or B) of the fire extinguisher configuration site corresponding to the danger level of the fire extinguisher configuration site of class A fire or class B fire;
k1—correction factor.
Ground buildings k1 = 1, underground buildings k1 = 13；
k2 = correction factor.
K2 = 1 without fire hydrants and fire extinguishing systems0；
k2 = 07；
K2 = 05；
With fire hydrant and fire extinguishing system or combustible open stacking, Class A, B, C liquid storage tanks, combustible gas storage tanks K2 = 03；
2.Calculation examples.
If there is a medium-hazard Class A fire extinguisher above-ground configuration site, its protection area is 360 hours, and there is no fire hydrant and fire extinguishing system, it is required to calculate the fire extinguishing level of the fire extinguisher configuration site. From the above we know that its s=360, u=15 a, k1=10,k2=1.0, then.
q=k1·k2·s/u=1.0×1.0×360/15=24(a)
Obviously, this 24(a) is the level of fire extinguishing that needs to be assigned to the place where the fire extinguisher is deployed.
If there is a fire hydrant in the place where the fire extinguisher is installed, the fire extinguishing level of the place where the fire extinguisher is installed is.
q=k1·k2·s/u=1.0×0.7×360/15=16.8(a)
If the fire extinguisher is equipped with a fire extinguishing system, the fire extinguishing level of the fire extinguisher is required.
q=k1·k2·s/u=1.0×0.5×360/15=12(a)
If the fire extinguisher is equipped with a fire hydrant and a fire extinguishing system, the fire extinguishing level of the fire extinguisher is required.
q=k1·k2·s/u=1.0×0.3×360/15=7.2(a)
2) The setting point needs to be equipped with the calculation and example of the fire extinguishing level.
1.Calculation formula: qe = q n
Where: QE - the fire extinguisher configuration site of each setting point needs to be equipped with fire extinguishing level, a or b;
n—The number of setting points in the fire extinguisher configuration site.
2.Calculation examples.
For example, the calculated value of the fire extinguishing level of a fire extinguisher configuration place is 24 (a), after considering the protection distance and the actual setting position of the fire extinguisher, assuming that three setting points are finally selected, then, we can calculate the fire extinguishing level of each setting point under normal circumstances, that is: q = 24 (a), n = 3, then qe=q n = 24 3 = 8 (a).
Therefore, the fire extinguishing level required for each setting point is 8 (a).
And the actual fire extinguishing level shall not be less than the fire extinguishing level that needs to be matched. The fire extinguishing level (expressed by qt) of all fire extinguishers actually configured in the fire extinguisher configuration site shall not be less than the fire extinguishing level (represented by q) of the fire extinguisher configuration site calculated according to the calculation formula, that is, qt q0.