Patent Publication Number: US-9849316-B2

Title: Tunnel fire protection system

Description:
PRIORITY DATA &amp; INCORPORATED BY REFERENCE 
     This application is a continuation application of U.S. patent application Ser. No. 14/895,881 filed Dec. 3, 2015, which is a 35 U.S.C. §371 application of International Application No. PCT/US2014/042473 filed Jun. 16, 2014, which claims the benefit of U.S. Provisional Patent Application No. 61/835,248, filed Jun. 14, 2013, each of which is incorporated by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present invention relates generally to vehicle transit fire protection systems, and more specifically, fire protection systems for tunnels having vehicle traffic. 
     BACKGROUND ART 
     Known fire protection systems for road tunnels include fixed firefighting systems that deliver water or other firefighting agent to address a vehicle fire such as, for example, a wheel well fire, a passenger compartment fire, multiple vehicle fires, tractor trailer fires, or fires involving flammable liquid spills or pallets. Water-based fixed firefighting systems can include deluge systems that employ water spray or water mist devices that are always open to deliver the water or water mist at a desired rate or flow (volume per unit of time) and at a desired density or application rate (flow per unit of area). Delivery of water to the sprinklers or nozzles is controlled by one or more fluid control valves, such as for example, deluge valves. The water delivery, control and application can be designed with the objective of protecting occupants in their vehicles, protecting occupants during escape on foot, and managing products of combustion. 
     The tunnel and the areas to be protected by the fire protection system generally include the roadway, the roof and/or ceiling above the roadway, and the sidewalls which extend from the roof to the roadway. For large tunnels, it can be desirable to divide the area of protection into zones, in which the response and delivery of water to the zones can be individually controlled. The size of the individual zones to be protected is defined by the available water supply and resulting hydraulics, e.g., flow, density and operating pressure requirements of the system and its water distribution devices. The ability of the system to apply water at a designed density within a given zone is a function of the number of devices in the zone, the coverage area of the individual devices, and the spacing and orientation of the devices relative to the protection area and any obstructions or system components within the zone. Generally, the coverage area of the individual device is a function of the geometric area covered by the spray or mist, the operating pressure of the device and its discharge characteristics. Spacing, installation and orientation of the water discharge devices is defined by the piping and fittings interconnecting the devices to one another and the water supply. The number of devices and the amount of piping employed can impact the overall cost of the system. Accordingly, it is desirable to minimize or optimize the number of devices and/or the amount of piping and fittings to meet the design objectives of the system. Although prior system designs hypothesize minimized supply piping, such designs do not detail the coupling arrangements between the device and the supply piping to provide the designed density and protection over a specified zone. 
     DISCLOSURE OF THE INVENTION 
     In one preferred embodiment of a fire protection system, a deluge fire protection system is provided for protection of an area having a surface for vehicular transit. The deluge fire protection system includes a main water supply pipe disposed a first distance from the surface and a horizontal spray nozzle arrangement disposed a second distance from the surface with the second distance being less than the first distance. The horizontal spray nozzle arrangement preferably includes a nozzle device having a deflector and a frame supporting the deflector and a coupling arrangement between the main water supply and the nozzle device. The frame has a body defining an orifice and a nozzle axis, the body has an inlet portion defining an inlet internal diameter and a preferably nominal external diameter. The coupling arrangement preferably defines a multi-flow path and preferably at least a two-direction flow path between the main water supply and the nozzle device. The two-direction flow path has an effective length of at least eight times a diameter of the inlet portion of the body of the nozzle device and a cross-sectional area along the coupling arrangement greater than the cross-sectional area defined by a diameter of the inlet portion. Preferably, the two-direction flow path has an effective length of at least eight times the internal diameter of the inlet portion of the body of the nozzle device and a cross-sectional area along the coupling arrangement greater than the cross-sectional area defined by the internal diameter of the inlet portion. Alternatively, the two-direction flow path preferably has an effective length of at least eight times the nominal external diameter of the inlet portion of the body of the nozzle device and a cross-sectional area along the coupling arrangement greater than the cross-sectional area defined by the nominal external diameter of the inlet portion. The nominal external diameter can be defined by an external thread, external groove or other external surface configuration of the inlet portion of the body of the frame of the nozzle device. 
     In another embodiment of a deluge fire protection system for an area having a surface for vehicular transit, the system includes a main water supply pipe and a horizontal spray nozzle arrangement. The preferred horizontal spray nozzle arrangement includes a nozzle device and a coupling arrangement between the main water supply and the nozzle device. The preferred nozzle device has a deflector and a frame supporting the deflector. The frame has a body defining an orifice and a nozzle axis; and includes an inlet fitting with an external thread of a nominal diameter. The coupling arrangement between the main water supply and the nozzle device preferably delivers water to the inlet fitting at a preferred working pressure ranging from about 10 psi. to about 30 psi. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate exemplary embodiments of the invention, and together, with the general description given above and the detailed description given below, serve to explain the features of the preferred embodiments of the invention. It should be understood that the preferred embodiments are some examples of the invention as provided by the appended claims. 
         FIG. 1A  is a partial elevation view schematic of a preferred fire protection system. 
         FIG. 1B  is a partial plan view schematic of the system of  FIG. 1A . 
         FIG. 2A  is one embodiment of a horizontal spray nozzle arrangement for use in the system of  FIG. 1A . 
         FIG. 2B  is another embodiment of a horizontal spray nozzle arrangement for use in the system of  FIG. 1A . 
         FIGS. 3, 3A, and 3B  are various views of a preferred nozzle device for use in the arrangements of  FIGS. 2A and 2B . 
         FIGS. 4A-4L  are various embodiments of the fire protection system of  FIG. 1A  with various configurations and combinations of the horizontal spray nozzle arrangements of  FIGS. 2A and 2B . 
         FIG. 5A  is a plan view schematic of a preferred deluge fire protection system adjacent a prior art system. 
         FIG. 5B  is an elevation view of the system of  FIG. 5A  along line VB-VB. 
     
    
    
     MODE(S) FOR CARRYING OUT THE INVENTION 
     Shown in  FIGS. 1A and 1B  are respective schematic elevation and plan partial views of a preferred fire protection system for protection of a vehicle transit area A. More specifically, shown is a portion of a vehicle tunnel fire protection system  10  for the transit area A. Generally, the fire protection system  10  includes a main water supply pipe  12  suspended above a vehicle transit surface S of the transit area A, e.g., public or private access roadway, which defines one or more vehicle directions of travel TD. The main water supply pipe  12  is preferably suspended beneath a roof R of the transit area A and is more preferably suspended from the ceiling C of the roof R. The system  10  preferably defines a first ceiling-to-surface distance H 1 . 
     The system  10  includes one or more horizontal spray nozzle arrangements  100  coupled to the main supply pipe and suspended above the surface S of the transit area A at a second nozzle arrangement-to-surface distance H 2 . The distance H 2  is preferably a minimum of about 18 feet. As described in greater detail below, the horizontal spray nozzle arrangement  100  includes a nozzle frame, including an inlet portion, and a deflector defining a nozzle axis X-X which preferably extends parallel to the surface S. Each horizontal spray nozzle arrangement  100  and its deflector distribute firefighting fluid, i.e., water to define a protection coverage area CA over which water is distributed by the deflector. The coverage area CA of the nozzle arrangement  100  is defined by a first coverage distance CD in the direction of the nozzle axis X-X and a second coverage distance LD which extends orthogonally from the nozzle axis. The cover area CA is preferably defined by (2×LD))×CD. When the system  10  includes two or more horizontal nozzle arrangements adjacent one another, the nozzle arrangements  100   a ,  100   b  define a coverage area CA and an adjacent coverage area ACA. 
     Shown in  FIGS. 2A and 2B  are preferred embodiments of a horizontal spray nozzle arrangement  100 ,  100 ′ for use in the system  10 . The horizontal spray nozzle arrangement  100  is coupled to and preferably extends from the outlet  14  formed in the main supply pipe  12 . Each horizontal nozzle spray arrangement  100  includes one or more nozzle devices  200  and a coupling arrangement  110  for coupling the nozzle device(s)  200  to the main water supply pipe  12 . The preferred coupling arrangement  110  preferably defines multiple flow paths and more preferably defines at least a two-direction flow path between the main water supply  12  and the nozzle device  200  and its frame  202 . With reference to  FIG. 2A , the coupling arrangement  110  defines a first flow direction FD 1  and at least a second flow direction FD 2  to define the complete flow path from the main water supply pipe  12  to the nozzle device  200 . The first and second flow direction paths FD 1 , FD 2  are preferably skewed or angled with respect to one another and more preferably orthogonal with respect to one another to define an included angle θ 1  between the first and second flow directions FD 1 , FD 2 . In one preferred aspect, the multi-flow direction flow path aligns the horizontal nozzle axis X-X substantially parallel to the surface S. Additionally, the preferred coupling arrangement defines an effective length and cross-sectional area to further define the flow of fluid to the nozzle  200  and provide a desired spray pattern for the protection of the area A. As used herein, the effective length of a coupling arrangement, pipe fitting or pipe assembly having a pipe fitting(s), is defined as the equivalent pipe length of a straight pipe when accounting for head loss due to the fitting(s) in the arrangement. The effective cross-sectional area of a coupling arrangement, pipe fitting or pipe assembly having a pipe fitting(s) is defined as the area of a plane defined by the width and more preferably a diameter of the interior surface of the arrangement disposed normal to the direction of flow through the arrangement. 
     The preferred coupling arrangement  110  includes a drop nipple  112  and a pipe fitting  114   a  coupled to the drop nipple  112 . The drop nipple  112  preferably extends from the outlet  14  of the main water supply pipe  12  vertically and more preferably toward the surface S to define the first direction FD 1  of the two-direction flow path. The outlet  14  defines a preferred nominal diameter of 2 inches. The drop nipple  112  preferably defines a nominal diameter of 2 inches and a nominal length ranging from 8 inches to 9 inches. The pipe fitting  114   a  extends from the drop nipple  112  to the nozzle device  200  to define the second direction FD 2  of the two-direction flow path. The second direction FD 2  preferably extends perpendicularly to the first direction FD 1 . 
     In one preferred embodiment of the coupling arrangement  110 , shown in  FIG. 2A , the pipe fitting  114   a  preferably includes an elbow fitting  114   a  and a reduction assembly. The preferred elbow fitting  114   a  is preferably a ninety degree (90°), 2 in.×2 in. elbow fitting  114   a . The elbow fitting  114   a  preferably defines an effective length of 8.5 feet. Preferably disposed between the elbow fitting  114   a  and the preferably horizontally disposed nozzle device  200  is a reduction assembly to define a preferred cross-sectional area along the coupling arrangement  110  that is greater than the cross-sectional area defined by the inlet portion of the nozzle device  200 . In one preferred embodiment, the cross-sectional area ranges from about 1.25 square inches to about 4.5 square inches. A preferred reduction assembly includes a second nipple and more preferably an arm-over nipple  116  having a preferably nominal two inch diameter and a pipe reducing fitting  118  and more preferably a 2 in.×1 in. reducing fitting. The preferred reduction assembly defines a cross-sectional area of about 1.25 square inches and is more preferably 1.36 square inches between the elbow fitting  114   a  and the nozzle device  200 . 
     Shown in  FIG. 2B  is another preferred embodiment of the horizontal spray nozzle arrangement  100 ′ having a coupling arrangement  110  defining multi-directional flow paths skewed or angled with respect to one another between the main water supply pipe  12  and the nozzle device  200 . As shown, the coupling arrangement  110  preferably defines three flow paths FD 1 , FD 2 , FD 3  in which at least two flow paths are skewed with respect to one another. In the preferred embodiment of  FIG. 2B , the second and third flow paths FD 2 , FD 3  are orthogonal to the first flow path FD 1  and axially aligned with one another. The flow paths FD 1 , FD 2 , FD 3  define included angles θ 1 , θ 2 , θ 3  between one another in which at least one of the included angles defines an angle of less than 180 degrees (180°). For the preferred embodiment of  FIG. 2B , the first included angle θ 1  between the first flow path FD 1  and FD 2  is about ninety degrees (90°), the second angle θ 2  between the first flow path FD 1  and FD 3  is about ninety degrees (90°), and the third angle θ 3  between the first flow path FD 2  and FD 3  is about 180 degrees (180°). The coupling arrangement  110  can be alternatively configured such that each of the flow paths is skewed or angled with respect to the other flow paths. 
     The horizontal spray nozzle arrangement  100 ′ preferably includes a drop nipple  112  and a pipe fitting  114   b  coupled to the drop nipple  112 . The drop nipple  112  preferably extends from the outlet  14  of the main water supply pipe  12  vertically and more preferably toward the surface S to define the first direction FD 1  of the multi-direction flow path. The drop nipple  112  preferably defines a nominal diameter of 2 inches and a nominal length ranging from 8 inches to 9 inches. The pipe fitting  114   b  preferably includes a tee fitting  114   b  and a pair of reduction assemblies which extends from the drop nipple  112  to each of a first nozzle device  200   a  and a second nozzle device  200   b  to respectively define the second direction FD 2  and third direction FD 3  of the multi-direction flow path of the coupling arrangement  110 . The first and second nozzle devices  200   a ,  200   b  are disposed in preferred back-to-back relation with respect to one another. The preferred tee fitting is preferably a 2 in.×2 in.×2 in. tee fitting  114   b . The tee fitting  114   b  preferably defines an equivalent length of twelve feet (12 ft.). Preferably respectively disposed between each of the tee fitting  114   b  and the preferably horizontally disposed first and second nozzle devices  200   a ,  200   b  are a preferred first and second reduction assembly each including a nipple and reducer arrangement and in particular, an arm-over nipple  116   a ,  116   b  having a preferably nominal two inch diameter and a pipe reducing fitting  118   a ,  118   b  and more preferably a 2 in.×1 in. reducing fitting. The reduction fittings preferably define an effective cross-sectional area of about 4.5 square inches and more preferably a cross-sectional area of 4.45 square inches between the tee fitting and the nozzle device  200   a ,  200   b.    
     The 90-degree elbow  114   a  and tee-fitting  114   b  of the preferred coupling arrangements orient the first and at least the second flow paths FD 1 , FD 2  orthogonal to one another. Alternatively, the pipe fitting  114  can be embodied as a 120 degree (120°) elbow or three-way fitting to skew the flow paths accordingly with respect to one another. Moreover, the coupling arrangement  110  can include more than one pipe fitting  114  and an appropriate number of corresponding nipples provided the resulting coupling arrangement  110  locates and orients the nozzle device  200  and delivers the working fluid pressure to the nozzle device  200  in a manner suitable for protection of the area A. Preferably, the resulting coupling arrangement defines an effective pipe length and cross-sectional area as described above. The cross-sectional area(s) defined by the coupling arrangement  110  may be variable over one or more portions of the length of the coupling arrangement including having a cross-sections smaller than that defined by the inlet portion  208  of the nozzle device  200 . Alternatively, the cross-section can be constant over the entire length of the coupling arrangement provided a sufficient flow of fluid is provided to the nozzle device for protection of the area A as described herein. Alternatively or in addition to, the coupling arrangement  110  can define an internal reservoir or expansion in the fluid flow path to hold, slow down or circulate fluid and provide fluid flow characteristics to the nozzle device to provide the desired spray pattern for protection of the area A. For example, the coupling arrangement  110  can include an elbow or tee-fitting  114  with an expanded volume relative to the drop nipple  112  or reduction assembly to define an internal volume to collect and provide a fluid reservoir to supply the nozzle device(s)  200 . 
     The preferred nozzle device  200  includes a frame  202  and a deflector  204  supported from the frame  202 . Shown in  FIGS. 3, 3A and 3B  is a preferred embodiment of the nozzle device  200 . The preferred frame  202  includes a body  202   a  having an internal surface that defines an internal passageway  206  extending along the nozzle axis X-X and an outlet or orifice  206   a  of the body  202   a . The internal passageway  206  and orifice  206   a  define a K-factor of the nozzle device  200  of 8.0 GPM/(PSI) 1/2  or greater, and more preferably, a nominal K-factor of 25.2 GPM/(PSI) 1/2 . As used herein, the nominal K-factor is defined as a constant representing the sprinkler discharge coefficient that is quantified by the flow of fluid in gallons per minute (GPM) from the sprinkler outlet divided by the square root of the pressure of the flow of fluid fed into the inlet of the sprinkler passageway in pounds per square inch (PSI). The nominal K-factor is expressed as GPM/(PSI) 1/2 . Industry accepted standards, such as for example, the National Fire Protection Association (NFPA) standard entitled, “NFPA 13: Standards for the Installation of Sprinkler Systems” (2013 ed.) (“NFPA 13”) provide for a rated or nominal K-factor or rated discharge coefficient of a sprinkler as a mean value over a K-factor range. For example, for a K-factor equal to greater than 8.0, the following nominal K-factors are provided (with the K-factor range shown in parenthesis): (i) 8.0 (7.4-8.2) GPM/(PSI) 1/2 ; (ii) 11.2 (11.0-11.5) GPM/(PSI) 1/2 ; (iii) 14.0 (13.5-14.5) GPM/(PSI) 1/2 ; (iv) 16.8 (16.0-17.6) GPM/(PSI) 1/2 ; (v) 19.6 (18.6-20.6) GPM/(PSI) 1/2 ; (vi) 22.4 (21.3-23.5) GPM/(PSI) 1/2 ; (vii) 25.2 (23.9-26.5) GPM/(PSI) 1/2 ; and (viii) 28.0 (26.6-29.4) GPM/(PSI) 1/2 . 
     The body  202   a  and its internal and external surfaces further define an inlet portion or fitting  208  of the frame  202 . The inlet portion  208  of the frame  202  is preferably configured for forming a mechanical connection to join the nozzle device  200  to, for example, the coupling arrangement  110 . In a preferred embodiment of the body  202   a , the inlet portion  208  preferably includes an external thread  210 . The external thread  210  defines a nominal diameter of the frame  202 . The external thread  210  of the preferred nozzle device  200  defines a preferred nominal diameter of one inch NPT or ISO 7-R 1. Alternatively, the inlet portion  208  can include an external groove of a nominal diameter for forming a grooved coupling connection. The inlet portion  208  can be alternatively configured to form the mechanical connection. For example, the internal surface of the inlet  208  can include an internal thread for forming a threaded connection. 
     As previously described, the preferred coupling arrangement  110  includes a plurality of pipes, nipples and/or fittings to define the two-direction flow path and more preferably define an effective length and cross-section. The preferred effective length of the coupling arrangement  110  is at least eight to ten times a nominal diameter of the inlet fitting  208 . For example, the effective length of the coupling arrangement  110  is at least eight to ten times the nominal diameter of the external thread  210  of the body  202   a  of the horizontal spray nozzle device  200 ; or alternatively, at least eight to ten times the nominal diameter defined by an external groove of the body  202   a . The preferred effective cross-sectional area of the coupling arrangement, along the effective length, is greater than the cross-sectional area defined by a nominal diameter of the inlet fitting  208 . The cross-sectional area of the inlet fitting can be defined by the internal diameter of the inlet portion  208  or may be alternatively defined by the external surface of the inlet portion  208 , for example, by the nominal diameter of an external thread, groove or other coupling surface configuration. 
     The preferred frame  202  preferably includes a pair of frame arms  202   b  to support the deflector  204  from the body  202   a . The pair of frame arms  202   b  are preferably disposed about the orifice  206   a  to define a plane P 1 . The nozzle axis X-X is preferably defined by the intersection of the plane P 1  and a second plane P 2 , which is perpendicular to the first plane P 1  and symmetrically bisects the device  200 . The deflector  204  preferably includes a face plate portion  204   a  disposed orthogonal to the nozzle axis X-X and a canopy portion  204   b  having a leading edge  205 . The face plate  204   a  is preferably disposed between the leading edge  205  and the body  202   a . In addition, the leading edge  205  is preferably radially spaced from the nozzle axis X-X and extends substantially parallel to the first plane P 1 . The deflector  204  further preferably includes a plurality of tines  212  extending radially from the face plate portion  204   a  and disposed to one side of the first plane P 1  opposite the canopy portion  204   b . Each of the plurality of tines  212  terminates in a peripheral edge  212   a . The peripheral edges  212   a  are preferably aligned along a perimeter of a common circle Cc centered on the nozzle axis. Additional features of a preferred nozzle device  200  for use in the system  10  is embodied in the nozzle device shown and described in U.S. Provisional Application No. 61/835,248. 
     Referring again to  FIGS. 1A and 1B , the preferred coupling arrangements  110 , in addition to coupling the nozzle device  200  to the main water supply pipe  12 , locates the nozzle device  200  at a vertical distance H 2  above the surface S and orient the nozzle device or devices and its horizontal axis X-X to the main water supply pipe  12 . Accordingly, the horizontal axis X-X can be oriented parallel to the linear alignment of the main water supply pipe  12  or alternatively skewed or angled to and more preferably perpendicular to the linear alignment of the main water supply pipe  12 . The linear alignment of the main water supply  12  preferably runs parallel to the direction (bi-direction) of traffic flow TD, but may alternatively run perpendicular to the direction of traffic TD. 
     The protection area A is further preferably defined by a pair of sidewalls SW which are spaced apart by the surface S and extend in the direction of the ceiling C. The system  10  includes one and can include more than one main water supply pipe  12  with each main water supply pipe including one or more horizontal spray nozzle arrangements  100  to define a coverage area or zone of protection in the area A. Shown in  FIGS. 4A-4L  are various embodiments of the fire protection system  10  in which there are one or more main water supply pipes  12  with their horizontal spray nozzle arrangements  100  in varying orientations. More specifically, shown in the respective plan and elevation views of  FIGS. 4A and 4B  is a single main water supply pipe  12  preferably centered between the sidewalls SW of the protection area A and extending in the direction (bi-direction) TD of traffic flow. The supply pipe  12  includes a plurality of horizontal arrangements  100   a ,  100   b ,  100   c , each having a first nozzle device  200   a  and a second nozzle device  200   b  in a back-to-back relationship as preferably previously described with respect to  FIG. 2B . The horizontal arrangements  100   a ,  100   b ,  100   c  are preferably configured so that the axes X-X of the nozzle devices  200   a ,  200   b  are oriented perpendicular to the main water supply pipe  12 . Shown in  FIGS. 4C and 4D  is an alternate embodiment in which the horizontal arrangements  100   a ,  100   b ,  100   c  are configured with the back-to-back nozzles  200   a ,  200   b  oriented so that their axes X-X are oriented parallel to the main water supply pipe  12 . 
     Shown in  FIGS. 4E-4H  are alternate embodiments of the system  10  in which there are multiple and more preferably two water main supply pipes  12   a ,  12   b  oriented in the direction (bi-direction) TD of vehicle traffic. The water supply pipes  12   a ,  12   b  are preferably spaced such that the pipes  12   a ,  12   b  are centered between the sidewalls SW. Each of the main water supply pipes  12   a ,  12   b  include a plurality of horizontal spray nozzle arrangements  100   a ,  100   b ,  100   c , each preferably configured with first and second nozzle device  200   a ,  200   b  in a back-to-back arrangement. For the embodiments shown in  FIGS. 4E-4H , the horizontal spray nozzle arrangements  100   a ,  100   b ,  100   c  are configured so that all the nozzle devices  200   a ,  200   b  of each of the main water supply pipes  12  are aligned in a single direction. For example as shown in the plan view of  FIG. 4E , all the nozzle devices  200   a ,  200   b  are oriented so that their axes X-X extend parallel to supply pipes  12   a ,  12   b . Alternatively shown in the plan view of  FIG. 4G , the horizontal spray arrangements  100   a ,  100   b ,  100   c  are configured so as to orient the nozzle axes X-X perpendicular to the supply pipes  12   a ,  12   b.    
     Referring now to the respective plan and elevation views of  FIGS. 41 and 4J , an alternate embodiment of the fire protection system  10  is shown having multiple main water supply pipes  12   a ,  12   b  centered between the side walls SW. In this embodiment, the horizontal spray nozzle arrangements  100   a ,  100   b ,  100   c  of supply pipe  12   a , are configured differently from the spray nozzle arrangements  100   a ′,  100   b ′,  100   c ′ of supply pipe  12   b . More preferably, the horizontal spray nozzle arrangements  100   a ,  100   b ,  100   c , of one supply pipe are oriented perpendicular to the main water supply pipe  12   a ; and the spray nozzle arrangements  100   a ′,  100   b ′.  100   c ′ of the main water supply pipe  12   b  are oriented parallel to their supply pipe  12   b.    
     Shown in  FIGS. 4K and 4L  is yet another embodiment of the system  10 . The system includes multiple and more preferably two water supply pipes  12   a ,  12   b  spaced and centered between the sidewalls SW of the protection area A in the direction (bi-direction) TD of traffic flow. Each of the water supply pipes  12   a ,  12   b  includes a plurality of horizontal spray arrangements  100   a ,  100   b ,  100   c , each preferably configured with a single nozzle device  200  oriented with its nozzle axis X-X perpendicular to the main water supply pipe  12   a ,  12   b . Accordingly, the coupling arrangement  110  of each horizontal spray nozzle arrangement  100  includes an elbow fitting as shown and described with respect to  FIG. 2A . The main water supply pipes  12   a ,  12   b  are preferably located so that the nozzle devices deflect water in a direction toward the center of the protection area A. More preferably, the main water supply pipes  12   a ,  12   b  are disposed closer to one wall with its spray directed in the direction of the oppositely located sidewall and away from the closer wall. 
     The nozzle devices  200  of the system  10  are preferably always in an open state such that upon water delivery to the nozzle device  200  and its inlet, water is free to discharge from the nozzle outlet  206   a  for distribution by the deflector  204  over the area A to be protected. Accordingly, the system  10  is preferably configured as a deluge fire protection system  10 . Fluid or water delivery to the main water supply pipes (P) and horizontal spray nozzle arrangements  100  is preferably controlled by a fluid control valve and more preferably by a deluge fluid control valve  1300  as schematically shown in the deluge fire protection system  1010  in  FIG. 5A . A preferred deluge valve for use in the system  1010  is shown and described in U.S. Provisional Application No. 61/835,428. Actuation and operation of the deluge valve  1300  can be automatic, manual or a combination of both. The system  1010  can include one or more sensors  15  disposed about the protection area A to detect a fire hazard for actuation of the valve  1300 . The sensors  15  are preferably coupled to the control  17  which actuates and controls the valve  1300 . The sensors  15  can be any one of spot heat detectors; linear heat detectors; passive smoke detectors; active smoke (aspirating) detectors; optical sensors (IR, UV, UV/IR) and/or closed-circuit television (CCTV). 
     The deluge fire protection system  10  is hydraulically designed such that water distribution from the nozzle device defines the desired coverage area CA, as shown in  FIG. 1B , with a desired distribution density. In one embodiment of the system  10 , each nozzle device  200  distributes water at a preferred density (volumetric flow rate per area) of about 0.25 gallons per minute per square foot (GPM/SQ. FT). As previously described, the coverage area is preferably defined by the water distribution throw distance CD in the direction of the nozzle axis X-X and its lateral distribution distance LD in the direction perpendicular to the nozzle axis X-X. The coverage is preferably a function of the operating pressure range of the nozzle and its discharge coefficient or nominal K-factor as previously described. For the preferred nozzle device of  FIG. 3 , the K-factor is a nominal 25.2 and the preferred working pressure ranges from a minimum pressure of about 10 psi. to a maximum pressure of about 30 psi. The working pressure may be lower than 10 psi. or higher than 30 psi. provided the delivered to the nozzle device  200  provides for a suitable spray pattern in the protection area A as described. As used herein, the term “about” is understood as within a range of normal tolerance in the art, for example within 2 standard deviations of the mean. “About” can be understood as within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated value. Unless otherwise clear from context, all numerical values provided herein are modified by the term about. Referring again to  FIG. 1B , the working pressure range preferably defines the range of the throw distance CD of the preferred nozzle  200  which preferably ranges from a minimum CD1 of about 20 feet and more preferably 19 feet-seven inches to a maximum CD2 of about 25 feet and more preferably 24 feet-seven inches. Over the entire preferred working pressure range, the preferred nozzle device  200  distributes water laterally to one side of the axis a lateral distance LD of about 8 feet and more preferably 8 feet-2 inches or a total of 16 feet about the nozzle axis X-X. The preferred spacing between adjacent nozzle devices  200  maximizes the coverage of each nozzle device, and therefore the preferred spacing is preferably twice the lateral distance LD of adjacent nozzles. For the preferred nozzle, a preferred spacing between adjacent nozzles is about sixteen feet (16 ft.). As shown in  FIG. 1A  and depending upon the location and orientation of the horizontal spray arrangement nozzle device  200  relative to the sidewalls SW, the water distribution can define a maximum vertical height Z on the sidewall SW to which the distributed water will reach. In one preferred embodiment, the water distribution from the nozzle  200  defines a maximum vertical height Z of about 4.5 meters. The sidewalls SW and the ceiling C are schematically shown in  FIG. 1A  as being planar and orthogonal to one another. However, it should be understood that either or both of the sidewalls SW and roof can be non-planar as seen for example in  FIG. 5B . Moreover, because the ceiling may define a variable ceiling-to-surface height H 1 ′, multiple horizontal spray nozzle devices may define various distances H 2 ′ from the surface S of the protection area A. The previously described working pressure range is one preferred range to provide for the desired distribution densities, coverage areas CA and/or vertical height Z. However, it should be understood that the working pressure range can be adjusted accordingly, i.e., expanded or lowered from its maximum or minimum, to effect a desired discharge density and/or geometry to suit the particular application. 
     The protection area A and its surface S can be divided into multiple zones to provide for zoned protection by the system  10 ,  1010 . More specifically, the system  10 ,  1010  can be divided into portions and configured to provide selective operation. Thus for example, in the case of a fire event detected in a particular zone, the system  10 ,  1010  would selectively discharge in the particular zone. To provide for selective discharge, fluid discharge into each zone would be controlled by its own designated fluid control valve  1300 . A zone is preferably defined by the width of the surface S or tunnel to be protected and a predetermined length in the direction (bi-direction) of travel through the area A of the tunnel. The size of each zone of protection may range from about 15 meters×25 meters square to about 15 meters×75 meters square. For the preferred protection zone size of 15 meters×50 meters square, it has been determined a hydraulic demand of about 2000 gallons per minute is preferred. Depending upon the configuration (single nozzle, back-to-back), orientation (parallel; perpendicular to main water supply pipe  12 ) and total coverage area CA defined by a particular horizontal spray nozzle arrangement  100  and its nozzle device(s)  200 , each zone can be protected by one or more of the horizontal spray nozzle arrangements  100 . Thus, to determine the number of horizontal spray nozzle arrangements  100  for a zone, one would divide the total hydraulic demand of the zone by the total coverage area CA provided by a single horizontal spray nozzle arrangement  100 . Referring again to  FIG. 5A , the preferred deluge fire protection system  1010  is shown adjacent a prior art or traditional deluge zone system  2020 . As can be seen, the preferred system  1010  can be configured with fewer horizontal spray nozzle arrangements  100  as compared to the number of fire protection devices  2200  used in the typical layout. 
     While the present invention has been disclosed with reference to certain embodiments, numerous modifications, alterations, and changes to the described embodiments are possible without departing from the sphere and scope of the present invention, as defined in the appended claims. Accordingly, it is intended that the present invention not be limited to the described embodiments, but that it has the full scope defined by the language of the following claims, and equivalents thereof.