FIRE PROTECTION SYSTEM FOR SLOPED COMBUSTIBLE CONCEALED SPACES
20210353988 · 2021-11-18
Inventors
- John DESROSIER (Plymouth, MA, US)
- Thomas Edwin ARCHIBALD (Midland, MI, US)
- Kevin Desmond Maughan (North Kingstown, RI, US)
- Kenneth Wayne ROGERS (Omer, MI, US)
- Kim Phillip GORDON (Sterling Heights, MI, US)
- Stephen J. Meyer (Chester Springs, PA, US)
Cpc classification
B05B1/06
PERFORMING OPERATIONS; TRANSPORTING
B05B1/267
PERFORMING OPERATIONS; TRANSPORTING
A62C3/00
HUMAN NECESSITIES
A62C35/60
HUMAN NECESSITIES
International classification
B05B1/06
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A fire protection system is provided for a space having a pitched roof constructed of structural members extending from a ridgeline to an eave, with respective channels therebetween. A first row of sprinklers is mounted to a first branch line extending generally parallel to the ridgeline. Each sprinkler is positioned within a respective channel, with consecutive sprinklers spaced apart having no less than one, and no more than five, channels therebetween. A second row of sprinklers, downslope from the first row, is mounted to a second branch line extending generally parallel to the first branch line. Each sprinkler thereof is positioned within a respective channel, with consecutive second row sprinklers spaced apart as in the first row. Each second row sprinkler is also placed within a different channel from each first row sprinkler. A farthest number of channels between a first row sprinkler and a second row sprinkler is three.
Claims
1. A fire protection system for a combustible concealed space, the combustible concealed space comprising: a pitched roof constructed of a plurality of generally spaced apart structural members extending downwardly and outwardly from a ridgeline of the roof to an eave of the roof, the plurality of structural members defining respective channels therebetween, and the fire protection system comprising: a first row of sprinklers nearest the ridgeline, the sprinklers being mounted to a first branch line extending generally parallel to the ridgeline, wherein: (i) each sprinkler is positioned within a respective channel, (ii) consecutive sprinklers along the first row are spaced apart having no less than one channel therebetween without a sprinkler of the first row positioned therein, and (iii) consecutive sprinklers along the first row are spaced apart having no more than five channels therebetween without a sprinkler of the first row positioned therein, and; a second row of sprinklers mounted to a second branch line extending generally parallel to the first branch line, the second row of sprinklers being positioned downslope from the first row of sprinklers, wherein: (i) each sprinkler of the second row is positioned within a respective channel, (ii) consecutive sprinklers along the second row are spaced apart having no less than one channel therebetween without a sprinkler of the second row positioned therein, and (iii) consecutive sprinklers along the second row are spaced apart having no more than five channels therebetween without a sprinkler of the second row positioned therein; and wherein: (i) each sprinkler of the second row is placed within a different channel from each of the sprinklers of the first row; and (ii) a farthest number of channels between a sprinkler of the first row and a sprinkler of the second row is three channels without any sprinkler of the first row or sprinkler of the second row.
2. The fire protection system of claim 1, wherein the first row of sprinklers is positioned within approximately twelve inches of the ridgeline.
3. The fire protection system of claim 1, wherein each channel is approximately three feet wide.
4. The fire protection system of claim 1, wherein each channel is approximately two feet wide.
5. The fire protection system of claim 1, wherein horizontal spacing between the first row of sprinklers and the second row of sprinklers is between approximately six feet and approximately thirty-five feet.
6. The fire protection system of claim 1, wherein the horizontal spacing between the first row of sprinklers and the second row of sprinklers is between approximately six feet and approximately sixteen feet.
7. The fire protection system of claim 1, wherein each sprinkler of the first row of sprinklers is mounted to the first branch line projecting upwardly therefrom.
8. The fire protection system of claim 1, wherein each sprinkler of the first row of sprinklers includes a fluid deflector configured to produce a generally elliptical spray distribution pattern.
9. The fire protection system of claim 1, wherein each sprinkler of the second row of sprinklers is mounted to the second branch line in a generally perpendicular orientation relative to the pitched roof.
10. The fire protection system of claim 1, wherein each sprinkler of the second row of sprinklers includes a fluid deflector facing downslope.
11. The fire protection system of claim 10, wherein the deflector is configured to produce a substantially downslope distribution pattern.
12. A method of positioning fire protection sprinklers in a combustible concealed space having a pitched roof constructed of a plurality of generally spaced apart structural members extending downwardly and outwardly from a ridgeline of the roof to an eave of the roof, and the plurality of structural members defining respective channels therebetween, the method comprising the steps of: mounting a first row of sprinklers to a first branch line proximate the ridgeline and extending generally parallel to the ridgeline, wherein: (i) each sprinkler is positioned within a respective channel, (ii) consecutive sprinklers along the first row are spaced apart having no less than one channel therebetween without a sprinkler of the first row positioned therein, and (iii) consecutive sprinklers along the first row are spaced apart having no more than five channels therebetween without a sprinkler of the first row positioned therein, and; mounting a second row of sprinklers to a second branch line extending generally parallel to the first branch line positioned downslope from the first branch line, wherein: (i) each sprinkler of the second row is positioned within a respective channel, (ii) consecutive sprinklers along the second row are spaced apart having no less than one channel therebetween without a sprinkler of the second row positioned therein, (iii) consecutive sprinklers along the second row are spaced apart having no more than five channels therebetween without a sprinkler of the second row positioned therein, (iv) each sprinkler of the second row is placed within a different channel from each of the sprinklers of the first row; and (v) a farthest number of channels between a sprinkler of the first row and a sprinkler of the second row is three channels without any sprinkler of the first row or sprinkler of the second row.
13. The method of claim 12, further comprising the step of positioning the first branch line within approximately twelve inches horizontally of the ridgeline.
14. The method of claim 12, further comprising the step of positioning the second branch line downslope from the first branch line at a location defining a horizontal spacing between the first row of sprinklers and the second row of sprinklers between approximately six feet and approximately thirty-five feet.
15. The method of claim 12, further comprising the step of positioning the second branch line downslope from the first branch line wherein the horizontal spacing between the first row of sprinklers and the second row of sprinklers is between approximately six feet and approximately sixteen feet.
16. The method of claim 12, wherein the step of mounting the first row of sprinklers to the first branch line comprises mounting the sprinklers projecting upwardly from the first branch line.
17. The method of claim 12, wherein the step of mounting the second row of sprinklers to the second branch line comprises mounting the sprinklers projecting perpendicularly to the pitched roof.
18. The method of claim 12, wherein the step of mounting the first row of sprinklers to the first branch line comprises mounting sprinklers having respective fluid deflectors configured to produce a generally elliptical spray distribution pattern.
19. The method of claim 12, wherein the step of mounting the second row of sprinklers to the second branch line comprises mounting sprinklers having fluid deflectors facing downslope.
20. The method of claim 19, wherein the fluid deflectors of the sprinklers of the second row are respectively configured to produce a substantially downslope distribution pattern.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The following description of preferred embodiments of the disclosure will be better understood when read in conjunction with the appended drawings. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings:
[0012]
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[0024]
DETAILED DESCRIPTION OF THE DISCLOSURE
[0025] Certain terminology is used in the following description for convenience only and is not limiting. The words “lower,” “bottom,” “upper” and “top” designate directions in the drawings to which reference is made. The words “inwardly,” “outwardly,” “upwardly” and “downwardly” refer to directions toward and away from, respectively, the geometric center of an attic space or a sprinkler, and designated parts thereof, in accordance with the present disclosure. Unless specifically set forth herein, the terms “a,” “an” and “the” are not limited to one element, but instead should be read as meaning “at least one.” The terminology includes the words noted above, derivatives thereof and words of similar import.
[0026] It should also be understood that the terms “about,” “approximately,” “generally,” “substantially” and like terms, used herein when referring to a dimension or characteristic of a component of the invention, indicate that the described dimension/characteristic is not a strict boundary or parameter and does not exclude minor variations therefrom that are functionally similar. At a minimum, such references that include a numerical parameter would include variations that, using mathematical and industrial principles accepted in the art (e.g., rounding, measurement or other systematic errors, manufacturing tolerances, etc.), would not vary the least significant digit.
[0027] Referring to the drawings in detail, wherein like numerals indicate like elements throughout, there is shown in
[0028] As should be understood by those of ordinary skill in the art, the ridgeline 56 is defined by the intersection of two adjoining portions of the roof 52, each extending downwardly and at least one extending outwardly from the ridgeline 56 to an eave 58. Commonly, there are two adjoining pitched portions of the roof 52, generally mirroring one another relative to the ridgeline 56 (see
[0029] The sprinkler system 10 comprises a plurality of sprinklers 12, 14 (shown schematically in
[0030] As shown in
[0031] Along the first row R1 (as well as along any other row of sprinklers 12, 14), adjacent, i.e., consecutive, sprinklers 12 are spaced having a maximum of five channels 60 therebetween (see
[0032] Turning to row R2 (employed for attic spaces 50 spanning greater than thirty-five feet from peak 56 to eave 58, and generally for attic spaces 50 spanning greater than sixteen feet from peak 56 to eave 58), the sprinklers 14 of row R2 are positioned relative to one another (along the same row) according to the conditions of row R1. While abiding by the positioning conditions of row R1, the sprinklers 14 of row R2 are also all offset from the sprinklers 12 of row R1. Namely, as shown in
[0033] As previously explained, row R2 is positioned downslope from row R1, and horizontally spaced therefrom by between approximately six (6) feet and approximately thirty-five (35) feet. Employing rows R1 and R2 may be utilized to protect an attic space 50 spanning a maximum of seventy-five (75) feet from peak 56 to eave 58 (i.e., one hundred and fifty (150) feet from eave 58 to eave 58). Sprinklers 14 (or 12) of any subsequent downslope row are spaced relative to one another (along the same row) according to the conditions of row R1, and are offset relative to the adjacent upslope row (i.e., the previous row closer to the ridgeline 56) according to the offset conditions of row R2 relative to row R1. Horizontal spacing of any such subsequent downslope row from the previous upslope row of is also between approximately six (6) feet and approximately thirty-five (35) feet.
[0034] Typically, the most challenging fires to reach with sprinklers start at the bottom of an attic space 50 (near the eave 58), and in the more common types of attic structures where the structural members 54 and the channels 60 extend down the attic slope (from the peak 56), the fire propagates up one or more of the channels 60. Heat and fire growth in an attic space 50 are directly related to the sloping structure and the channels 60 formed by the structural members 54. In these downslope channel type attic structures, fires generally propagate laterally, i.e., across channels 60, no more than a single channel 60 (between approximately eighteen inches and thirty-six inches wide, and generally approximately twenty-four inches wide) during the early stages of fire development. Therefore, to be most efficient, the focus of sprinkler operation should be prioritized downslope in the direction along the channels 60 of the pitched roof 52 before the lateral direction. By addressing and suppressing the fire ignition location early in the development of a fire, with sprinklers 12, 14 positioned for better efficiency of water delivery, much less water can be utilized to dispose of the fire.
[0035] Due to the channeling effect and upward heat propagation, staggering sprinklers 12, 14 ensures there will be a sprinkler 12, 14 positioned within one or two channels 60 away from any fire propagation location, and a fire plume will be sure to activate a sprinkler 12, 14 in a nearby channel 60 between eave 58 and peak 56. Advantageously, offsetting, i.e., staggering/spacing, the sprinklers 12, 14 with respect to the channels 60 between the structural members allows for much faster activation of a sprinkler 12, 14 close to a fire and more effective sprinkler 12, 14 spray distribution, regardless of where the initial fire location is generated. Spacing the sprinklers 12, 14 relative to the channels 60, as described above, ensures that a sprinkler 12, 14 is located laterally, or along a channel 60, within the range where the hot gasses of a fire may be channeled. By spacing the sprinklers 12, 14 in the above described manner, the sprinklers 12, 14 are effectively placed to ensure quick activation during the beginning phases of a fire and better positioned for more efficient spray distribution, thereby utilizing significantly less water to dispose of the fire. Advantageously, via the above-described sprinkler positioning system, no more than five sprinklers 12 activate during a fire, and, therefore, the total system demand can be kept to between approximately eighty (80) and approximately one-hundred (100) GPM, which is less than half of the traditional “attic sprinkler” total system demand. This allows for the use of the present system in buildings where the current sprinkler demand makes attic systems not cost effective. Moreover, cold soldering (when water spray from one sprinkler falls upon an adjacent sprinkler and prevents the heat-sensitive element of the adjacent sprinkler from operating) is substantially prevented.
[0036] As should be understood, sprinkler configuration, in addition to sprinkler positioning, also contributes to effective fire protection in attic spaces 50. In one embodiment, as described in further detail below, the sprinklers 12 along row R1 (i.e., the row nearest the ridgeline 56) may be of one configuration and the sprinklers 14 along row(s) R2-R(n) (i.e., the rows downslope from the ridgeline 56) may be of another configuration, but the disclosure is not so limited. For example, where a row of sprinklers is employed at the eave 58, the sprinklers may be configured similarly to the sprinklers 12 along row R1. As previously explained, the focus of sprinkler operation in attic spaces 50 should be prioritized downslope in the direction along the channels 60 of the pitched roof 52 to be most efficient.
[0037] As shown,
[0038] The sprinkler frame 16 includes an at least partially externally threaded body 24, defining the proximal inlet 16a, the distal outlet 16b and the internal water passageway extending therethrough, which receives at least a portion of the sealing plug 22. The body 24 is mounted to, e.g., threadingly, the water line branch defining row R1 to receive water therefrom and through the internal water passageway through the body 24. Two frame arms 26a are radially positioned or diametrically opposed about the body 24 and extend axially therefrom toward the deflector 18. The frame arms 26a converge toward the sprinkler axis A-A to terminate at a terminal end 26b of the sprinkler frame 16 axially aligned along the sprinkler axis A-A. The deflector 18 is mounted upon the terminal end 26b of the sprinkler frame 16.
[0039] A compression screw 28 (
[0040] Turning to
[0041] As shown best in
[0042] As also shown best in
[0043] As should be understood by those of ordinary skill in the art, a fire heat plume travels predominantly up the slope from the origin of the fire toward the peak 56 in an attic space 50. Where the structural members 54 extend in the direction from the peak 56 to the eave 58, forming the channels 60 therebetween, the heat plume exhibits less rapid sideways/lateral spread across the channels 60 and more rapid and concentrated upslope spread. Wider spread is exhibited in areas where the structural members 54 extend laterally across the slope of the pitched roof 52, but the heat flow is nevertheless predominantly upslope. Heat from a fire ultimately accumulates at the peak 56, and a heat layer develops that is thickest directly upslope from the origin of the fire.
[0044] One advantage of the generally circular spray distribution of the sprinklers 12 is the wide projection pattern/coverage area thereof. Accordingly, when the sprinklers 12 along row R1 are activated, they provide a relatively wide area cooling effect, protecting wide areas of the peak 56 of the attic space 50 from fire growth. Moreover, the wide projection pattern of the sprinklers 12 also limits concentrated heat plume rise along a channel 60, up the slope of the roof 52 from the origin of a fire, forcing the heat plume downslope and increasing sideways/lateral movement of the heat plume. Forcing a fire heat plume downslope and more laterally/sideways, facilitates activation of the nearest downslope sprinklers 14 (described in further detail below) of a subsequent row R2 or rows, closer to the fire. Additionally, the generally circular spray distribution of the sprinklers 12 along row R1 permits the sprinklers 12 to respond to fires from either downslope side of the attic space 50. Alternatively, the advantages of the generally circular spray distribution (wide peak area cooling and increased sideways plume projection downslope) may be achieved with a slightly elliptical pattern for better peak cooling or better downslope plume projection.
[0045] The sprinklers 12 may also be employed in a row nearest the eave 58, whereby the wide coverage area thereof may more efficiently reach restricted space at the intersection of the pitched roof 52 and the attic floor 53. At an eave 58, the sprinklers 12 spray reach far into the narrow crevice at the insertion. The sprinklers 12 may also be employed in areas of the attic space 50 where the structural members 54 extend perpendicularly to, i.e. laterally across, the slope of the pitched roof 52, e.g., a hip area, whereby heat rising toward the peak 56 exhibits increased lateral spread due to the direction of the structural members 54.
[0046] Turning to
[0047] The sprinkler frame 38 includes an at least partially externally threaded body 46, defining the proximal inlet 38a, the distal outlet 38b and the internal water passageway extending therethrough, which receives at least a portion of the sealing plug 44. The body 46 is connected, e.g., threadingly, with a water branch line 15 defining row R2 to receive water therefrom. Two frame arms 39 are radially positioned or diametrically opposed about the body 46 and extend axially therefrom toward the deflector 40. A compression screw 48 (
[0048] As shown best in
[0049] In one configuration, the sprinkler 14 is mounted on the row R2 with the axis B-B thereof oriented generally perpendicularly to the pitched roof 52, and with the deflector 40 facing downslope. Alternatively, the sprinkler 14 may be mounted with the axis B-B thereof oriented generally perpendicularly to the ground surface. Upon activation of the thermal trigger 42, e.g., shattering of the glass bulb, the sealing plug 44 is forced out by the upstream pressurized water from the branch line 15 and deflected away. The water sprays out from the water passageway in the body 38 and impacts the deflector 40 for distribution thereof in a desired spray pattern according to the design of the deflector 40. The combination of the U-shaped opening 45 and the covering spacer bar 43 deflects some pressurized water reaching the opening 45 a small distance upslope. In one embodiment, for example, the pressurized water is projected between approximately two (2) feet and approximately six (6) feet upslope, such as, for example four (4) feet, but the disclosure is not so limited.
[0050] The sprinkler 14 is designed, however, primarily for areas downslope from the peak 56, where heat plumes are channeling up the slope. As should be understood, there is minimal heat projection from a fire in the downslope direction in an attic space 50, and primarily upslope projection of heat from the fire. Accordingly, the deflector 40 is designed to cause extensive downslope water projection compared to the upslope water projection. Employing sprinklers 14 that project water primarily downslope also allows for increased sprinkler spacing up the slope. Sprinklers 12 positioned in an attic space 50 predominantly detect fires that are downslope therefrom, and, therefore, a primarily downslope spray pattern of the sprinklers 14 serves best to extinguish any fire detected by the sprinkler 12.
[0051] As shown best in
[0052] The deflector 40 further includes a deflecting portion 40b, having a generally planar, middle section 47a (as described in further detail below) oriented generally parallel to the mounting portion 40a and spaced further away from the sprinkler frame 38 than the mounting portion 40a. A connecting portion 40c connects the mounting portion 40a with the deflecting portion 40b.
[0053] The combination of the spacer bar 43, and the connecting and deflecting portions 40c, 40b of the deflector 40 projects the majority of water downslope. As shown best in
[0054] The deflector portion 40b also includes the generally planar middle section 47a and two opposing peripheral sections 47b extending from the middle section 47a at an included angle β (relative to the middle section 47a). As shown best in
[0055] As indicated above, the connecting and deflecting portions 40c, 40b of the deflector 40 channel water downslope. The peripheral sections 40c2 of the connecting portion 40c resist spillage of water sideways at the zone of the deflector 40 first struck by water projected from sprinkler frame 38. The peripheral sections 47b of the deflecting portion 40b are angled further away from the deflector 40 relative to the peripheral sections 40c2 of the connecting portion 40c and project the water across the width of the heat affected channeled zone from the fire traveling up the slope. In one embodiment, for example, the pressurized water is projected up to approximately forty (40) feet downslope, such as, for example, twenty (20) feet downslope, and having a spray width of approximately eight (8) feet, i.e., four (4) feet to each side, but the disclosure is not so limited. That is, the width of spray of the deflector 40 covers approximately four (4) channels 60, i.e., two (2) channels 60 on each side. Alternatively, the width of spray of the deflector 40 may cover approximately two and a half (2.5) channels 60 or three (3) channels 60 to each side. In one embodiment, between approximately 20% and approximately 40% of the water is projected upslope and between approximately 60% and approximately 80% of the water is projected downslope, but the disclosure is not so limited.
[0056] It will be appreciated by those skilled in the art that changes could be made to the embodiment(s) described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present disclosure, as set forth in the appended claims.