We have a small restaurant project where we are designing a water curtain for fire separation of open kitchen and dining area. The building is not required to be fully sprinklered.
Regarding the hydraulic calculations for the water curtain, I will mention the applicable code sections:
NFPA13-2007: 11.2.3 Water Demand Requirements - Hydraulic Calculation Methods.
11.2.3.1.1 The water supply for sprinklers shall be determined only from one of the following:
(1) Density/area curves of Figure 11.2.3.1.1 in accordance with the method of 11.2.3.2
(2) On the basis of the room design method in accordance with 11.2.3.3
(3) Special design areas in accordance with 11.2.3.4, at the discretion of the designer
NFPA13-2007: 11.3 Special Design Approaches.
NFPA13-2007: 11.3.3 Water Curtains.
11.3.3.1 Sprinklers in a water curtain such as described in 8.15.4 or 8.15.16.2 shall be hydraulically designed to provide a discharge of 3 gpm per lineal foot (37 L/min per lineal meter) of water curtain, with no sprinklers discharging less than 15 gpm (56.8 L/min) .
11.3.3.2 For water curtains employing automatic sprinklers, the number of sprinklers calculated in this water curtain shall be the number in the length corresponding to the length parallel to the branch lines in the area determined by 22.4.4.1.1.
11.3.3.3 If a single fire can be expected to operate sprinklers within the water curtain and within the design area of a hydraulically calculated system, the water supply to the water curtain shall be added to the water demand of the hydraulic calculations and shall be balanced to the calculated area demand.
11.3.3.4 Hydraulic design calculations shall include a design area selected to include ceiling sprinklers adjacent to the water curtain.
If I perform the hydraulic calculation per density/area method the existing water supply system will not be capable of meeting the demand. However, I believe I am going to the wrong direction since this is only a water curtain system, and I think the density and area of sprinkler operation from FIGURE 11.2.3.1.1 is not applicable.
What do you guys think?
Thank you.
Regarding the hydraulic calculations for the water curtain, I will mention the applicable code sections:
NFPA13-2007: 11.2.3 Water Demand Requirements - Hydraulic Calculation Methods.
11.2.3.1.1 The water supply for sprinklers shall be determined only from one of the following:
(1) Density/area curves of Figure 11.2.3.1.1 in accordance with the method of 11.2.3.2
(2) On the basis of the room design method in accordance with 11.2.3.3
(3) Special design areas in accordance with 11.2.3.4, at the discretion of the designer
NFPA13-2007: 11.3 Special Design Approaches.
NFPA13-2007: 11.3.3 Water Curtains.
11.3.3.1 Sprinklers in a water curtain such as described in 8.15.4 or 8.15.16.2 shall be hydraulically designed to provide a discharge of 3 gpm per lineal foot (37 L/min per lineal meter) of water curtain, with no sprinklers discharging less than 15 gpm (56.8 L/min) .
11.3.3.2 For water curtains employing automatic sprinklers, the number of sprinklers calculated in this water curtain shall be the number in the length corresponding to the length parallel to the branch lines in the area determined by 22.4.4.1.1.
11.3.3.3 If a single fire can be expected to operate sprinklers within the water curtain and within the design area of a hydraulically calculated system, the water supply to the water curtain shall be added to the water demand of the hydraulic calculations and shall be balanced to the calculated area demand.
11.3.3.4 Hydraulic design calculations shall include a design area selected to include ceiling sprinklers adjacent to the water curtain.
If I perform the hydraulic calculation per density/area method the existing water supply system will not be capable of meeting the demand. However, I believe I am going to the wrong direction since this is only a water curtain system, and I think the density and area of sprinkler operation from FIGURE 11.2.3.1.1 is not applicable.
What do you guys think?
Thank you.