Flaming droplet reduction in metal armored cables

Abstract

An optical communication cable is provided. Embodiments of the disclosure relate to an optical fiber cable. The optical fiber cable includes an exterior surface and an interior surface, the interior surface defining a bore extending along a length of the cable jacket. The optical fiber cable further includes an armor layer and a cable core disposed within the central bore. In various embodiments, a support layer is positioned between the interior surface of the cable jacket and the armor layer. Also disclosed are embodiments of an optical fiber cable having one or more binding components embedded in the cable jacket.

Description

Attorney Docket No.: HI24-085PCTFLAMING DROPLET REDUCTION IN METAL ARMORED CABLESRELATED APPLICATIONS

[0001] This application claims the benefit of priority of U.S. Provisional Patent Application No. 63 / 702,318, filed on October 2, 2024, and entitled “FLAMING DROPLET REDUCTION IN METAL ARMORED CABLES,” the content of which is relied upon and incorporated herein by reference in its entirety.BACKGROUND

[0002] The disclosure relates generally to optical fiber cables and, in particular, to optical fiber cables with an improved flaming droplet performance. Optical fiber cables are deployed in a variety of different operating environments, including aerial, subterranean, underwater, and over the ground. The optical fiber cable must be configured to withstand the conditions of its respective environment. The cable construction can vary to account for the conditions to which the optical fiber cable is exposed with the general goal of maintaining optical transmission despite being subjected to the harshest conditions of that environment, even if such conditions may be rare.

[0003] In particular, indoor and indoor / outdoor optical fiber cables are required to meet specific fire safety standards and can be rated in various categories such as flaming droplets, smoke production and acidity / corrosivity of the gases from burning. Some protective components of optical fiber cables, such as armor layers, are prone to causing flaming droplets to form when the optical fiber cable is burning.SUMMARY

[0004] According to an aspect, embodiments of the disclosure relate to an optical fiber cable. The optical fiber cable includes a jacket having an interior surface and an exterior surface. The interior surface defines a central bore extending along a longitudinal axis of the optical fiber cable. The exterior surface defines an outermost surface of the optical fiber cable. The optical fiber cable further includes a cable core, a metal armor layer, and a support layer. The cable core is disposed in the central bore and contains at least one optical fiber. The metal armor layer is disposed in the central bore between the cable core and the interior surface. The support layer is positioned between the interior surface of the cable jacket and the metal armor layer.Attorney Docket No.: HI24-085PCT

[0005] According to another aspect, embodiments of the disclosure relate to an optical fiber cable. The optical fiber cable includes a jacket having an interior surface and an exterior surface. The interior surface defines a central bore extending along a longitudinal axis of the optical fiber cable. The exterior surface defines an outermost surface of the optical fiber cable. The optical fiber cable further includes a cable core, a metal armor layer, and one or more binding components. The cable core is disposed in the central bore and contains a plurality of optical fibers. The metal armor layer is disposed in the central bore between the cable core and the interior surface of the cable jacket. The one or more binding components are embedded in the cable jacket between the interior surface and the exterior surface.

[0006] According to another aspect, embodiments of the disclosure relate to an optical fiber cable. The optical fiber cable includes a cable core including at least one optical fiber and a flame retardant cable jacket. The flame retardant cable jacket surrounds the cable core an includes an interior surface and an exterior surface. The interior surface defines a central bore extending along a length of the optical fiber cable. The optical fiber cable further includes a metal armor layer and a support layer or binding component. The metal armor layer is surrounded by the cable jacket. The support layer or binding component is positioned between the exterior surface of the cable jacket and the metal armor layer.

[0007] Additional features and advantages will be set forth in the detailed description that follows, and in part will be readily apparent to those skilled in the art from the description or recognized by practicing the embodiments as described in the written description and claims hereof, as well as the appended drawings.

[0008] It is to be understood that both the foregoing general description and the following detailed description are merely exemplary, and are intended to provide an overview or framework to understand the nature and character of the claims.

[0009] The accompanying drawings are included to provide a further understanding and are incorporated in and constitute a part of this specification. The drawings illustrate one or more embodiment s), and together with the description serve to explain principles and the operation of the various embodiments.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG. l is a cross-sectional view of an optical fiber cable according to an exemplary embodiment.Attorney Docket No.: HI24-085PCT

[0011] FIG. 2 is a cross-sectional view of an optical fiber cable according to another exemplary embodiment.

[0012] FIG. 3 A is a plan view of a first side of a flaming droplet sample according to an exemplary embodiment.

[0013] FIG. 3B is a plan view of a second side of the flaming droplet sample of FIG. 3 A according to an exemplary embodiment.

[0014] FIG. 4A is a plan view of a first side of a flaming droplet sample according to another exemplary embodiment.

[0015] FIG. 4B is a plan view of a second side of the flaming droplet sample of FIG. 4A according to an exemplary embodiment.

[0016] FIG. 5 is a cross-sectional view of an optical fiber cable without a cable core according to an exemplary embodiment.

[0017] FIG. 6 is a cross-sectional view of an optical fiber cable without a cable core according to another exemplary embodiment.DETAILED DESCRIPTION

[0018] Referring generally to the figures, various embodiments of an optical fiber cable with reduced risk of flaming droplets are shown. As will be generally understood, some jurisdictions require optical fiber cables to meet specific fire safety standards and can be rated in various categories such as flaming droplets, smoke production and acidity / corrosivity of the gases from burning. Many flame-retardant cables include armor layers to protect the cable core in harsh environments. However, the cable jacket that surrounds the armor layer is prone to losing bonding with the armor layer rapidly at elevated temperatures. Accordingly, any breaking of the cable jacket can lead to pieces of the cable jacket separating from the armor layer and falling off of the optical fiber cable. As will be discussed in greater detail below, such falling pieces may continue to burn and therefore be counted as flaming droplets for the purposes of a test for determining a fire rating of the cable. While there are some approaches to reducing flaming droplets such as adding special anti-dripping agents or changing the optical jacket material, these approaches are often expensive.

[0019] The inventors have determined that positioning fire resistant yarns, tapes, threads, wires etc. between the outer cable jacket and the armor of an optical fiber cable and / or embedded in the cable jacket of the optical fiber cable can reduce the risk of flaming dropletsAttorney Docket No.: HI24-085PCT forming during burning of the cable. The Applicant has found during prototype testing that during burning, such additional yarns, tapes, threads, wires, etc. provide support for the cable jacket to better retain the cable jacket in position. Specifically, the inventors surmise that the cable jacket material bonds to the yarns, tapes, threads, wires, etc. and therefore, the cable jacket material will not drip or melt away even when separated from the armor layer upon heating. As will be discussed in greater detail below, Applicant has conducted testing that indicates that the various embodiments of the optical fiber cable designs discussed herein will give enough time for full char formation and consumption of the combustible material in the cable jacket before the jacket falls on the ground. As such, the risk of flaming droplet formation for the various optical fiber cables discussed herein is expected to be reduced.

[0020] FIG. 1 depicts an example embodiment of an optical fiber cable 100. The optical fiber cable 100 includes a cable jacket 102. The cable jacket 102 includes an interior surface 104 and an exterior or outer surface 106. The interior surface 104 defines a central bore 108 of the optical fiber cable 100. The central bore 108 extends along a longitudinal axis of the optical fiber cable 100. In one or more embodiments, the exterior surface 106 of the cable jacket 102 is an outermost surface of the optical fiber cable 100.

[0021] In one or more embodiments, disposed within the cable jacket 102 is an armor layer 112. In one or more embodiments, the armor layer 112 is a metal tape. In one or more embodiments, armor layer 112 is steel tape. In one or more embodiments, armor layer 112 is aluminum tape. In one or more embodiments, armor layer 112 is formed from a metal material.

[0022] A cable core is disposed within the bore 108 of the cable jacket 102. Disposed within the core are one or more optical fibers 122. In one or more embodiments, including the embodiment of FIG. 1, the optical fibers 122 are contained within buffer tubes 120. In one or more embodiments, the optical fibers 122 are in a loose tube configuration such that the fibers 122 are disposed as individual loose fibers within the buffer tubes 120. In one or more embodiments, the buffer tubes 120 are stranded in one or more layers around a central strength member 124. In one or more embodiments, one or more of the fibers 122 can be a tight-buffered optical fiber. In still further embodiments, the optical fibers 122 in the bore 108 can be disposed in continuously-bonded planar ribbons or in intermittently-bonded ribbons.Attorney Docket No.: HI24-085PCT

[0023] In various embodiments, cable jacket 102 may be or include a variety of materials used in cable manufacturing, such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE) or high-density polyethylene (HDPE), polyvinyl chloride (PVC), polyvinylidene difluoride (PVDF), nylon, polyester or polycarbonate and their copolymers. In addition, the material of cable jacket 102 may include small quantities of other materials or fillers that provide different properties to the material of cable jacket 102. For example, the material of cable jacket 102 may include materials that provide for coloring, UV / light blocking (e.g., carbon black), burn resistance, etc. In various embodiments, buffer tubes 120 are formed from one or more polymer materials including polypropylene (PP), polybutylene terephthalate (PBT), polycarbonate (PC), polyamide (PA), polyoxymethylene (POM), poly(ethene-co-tetrafluoroethene) (ETFE), etc.

[0024] In one or more embodiments, optical fiber cable 100 is a flame-retardant optical fiber cable. In one or more embodiments, the cable jacket 102 is formed from a flameretardant material. In one or more embodiments, cable jacket 102 is formed from a low smoke zero halogen material. In one or more embodiments, cable jacket 102 includes one or more flame-retardant additives. For example, the flame-retarded additives can include metal hydrates and metal hydroxides, such as aluminum trihydrate (ATH) and / or magnesium dihydroxide (MDH) or borates.

[0025] In one or more embodiments, optical fiber cable 100 includes a binding layer 118. In one or more embodiments, binding layer 118 is positioned between cable jacket 102 and elements of the cable core such as the optical fibers 122, buffer tubes 120, and the like. In one or more embodiments, the binding layer 118 is disposed within a space enclosed by the armor layer 112 and surrounds other elements of the cable core. In one or more embodiments, the binding layer 118 is a thin polymeric film binder that, in various embodiments, is extruded around core elements such as the buffer tubes 120. In one or more embodiments, a layer 116 is positioned between binding layer 118 and armor layer 112. In one or more embodiments, layer 116 is at least one of yarn, a water-blocking tape, powder, or an additional binder wrap.

[0026] In one or more embodiments, optical fiber cable 100 includes an access feature shown as rip cord 114. In one or more embodiments, optical fiber cable 100 includes two rip cords 114 diametrically arranged around the core and that extend along a length of the optical fiber cable 100. In various specific embodiments, the rip cords 114 are diametrically opposed onAttorney Docket No.: HI24-085PCT opposite sides of the cable core. In other embodiments, optical fiber cable 100 can instead include access features other than ripcords 114, such as longitudinally-extending extruded strips of a polymer that is dissimilar to a polymer used to form the cable jacket 102, where such strips are disposed within the bulk of the cable jacket 102 (i.e., such that a material of the cable jacket 102 completely surrounds the extruded strips).

[0027] In various embodiments, optical fiber cable 100 includes a support layer 110. Support layer 110 is positioned between cable jacket 102 and armor layer 112. In various specific embodiments, support layer 110 comprises at least one of a thread, yarn, a fire resistant yarn, tape, or wire(s). By way of example, the support layer 110 can comprise a plurality of threads, yarns, or wires extending longitudinally straight (i.e., not stranded) along a length of the cable 100. In other embodiments, the support layer 110 can comprise a plurality of threads, yarns, or wires that are stranded or otherwise wrapped around the armor layer 112 prior to extruding the cable jacket 102 around the support layer 110. In still other embodiments, the support layer 110 can comprise a tape that extends longitudinally along a length of the cable 100 and is wrapped around the armor layer 112 prior to extrusion of the cable jacket 102. However constructed, elements of the support layer 110 can be formed from fire-resistant materials, such as, but not limited to glass yarns, fiberglass tape, metal wires, or the like.

[0028] As previously discussed, the inventors surmise that when a cable jacket is directly surrounding and / or bonded to an armor layer, cable jacket will lose adhesion to armor layer during burning of the cable as the temperature rises, making the optical fiber cable prone to flaming droplets. In contrast, in the various embodiments of optical fiber cable 100 discussed herein, the inventors have concluded that the support layer 110 positioned between the cable jacket 102 and the armor layer 112 will retain the cable jacket 012 and / or reduce the likelihood of the cable jacket 102 detaching from the optical fiber cable 100. The inventors surmise that the support layer 110 holds the cable jacket 102 even after the adhesion between the cable jacket 102 and armor layer 112 is lost.

[0029] In one or more embodiments, in addition to or in place of the support layer 110, yarns or fibers are added into cable jacket 102. In one or more embodiments, chopped yarns or fibers are added into cable jacket 102. In one or more embodiments, a net or a mesh of yarns or threads are added into cable jacket 102. In one or more embodiments, chopped yarns are coupled to a tape (e.g., water-blocking, steel tape, etc., not shown in FIG. 1) that is disposed within the cable jacket 102. For instance, such a tape can be passed through anAttorney Docket No.: HI24-085PCT extrusion die and the cable jacket 102 extruded around the armor layer 112 and / or the support layer 110 such that an extrudate that forms the cable jacket 102 flows around the tape and cools, forming the cable jacket 102 with the tape disposed therein. In such embodiments, during extrusion of the cable jacket 102, the jacket material will penetrate between the chopped yarns such that the yarns provide support for the cable jacket 102. In one or more embodiments, yarns are bonded to a polymer layer disposed between the armor layer and the cable jacket. In one or more embodiments, the yarns, threads, nets, etc. are stranded around the optical fiber cable after manufacturing, for example, during installation of the optical fiber cable.

[0030] FIG. 2 depicts another example optical fiber cable 200. The cable 200 is similar to the cable 100 in that the optical fiber cable 200 includes a cable jacket 202 that includes an interior surface 204 and an exterior surface 206 where the interior surface 204 defines a bore 208 of the optical fiber cable 200; an armor layer 212; and optical fibers 222 that are disposed within a space enclosed by the armor layer 212. In some embodiments, the optical fibers 222 can be disposed within buffer tubes 220 that are stranded around a central strength member 224. In further embodiments, the optical fiber cable 200 can include a binder layer 218 that can be used to constrain the buffer tubes 220 against the central member 224. In still further embodiments, the cable 200 can include an additional layer 216 disposed between the armor layer 212 and the binder layer 218, which layer 216 can be, for example, a water-blocking tape. Still further, the cable 200 can include rip cords 214 for providing an installer of the cable 200 access to core elements such as the fibers 222 and buffer tubes 220.

[0031] In various embodiments of the cable 200, one or more binding components 210 such as thread, tape, yarn, wire, etc. can be embedded within cable jacket 202 such that the binding components 210 extend longitudinally along the length of the cable 200 and within the cable jacket 202. The binding components 210 are generally positioned between interior surface 204 and exterior surface 206 of cable jacket 202. In one or more embodiments, at least two binding components 210 are embedded in cable jacket 202. In one or more embodiments, a different number of binding components are embedded in cable jacket 202 (e.g., at least 3, 4, 5, 6, 7, 8, 9, 10, etc.). As with the components of the support layer 110 of the cable 100, the binding components 210 of the cable 200 can be formed of fire-resistant materials, such as glass yarns or fiberglass tapes.

[0032] In one or more embodiments, a plurality of the binding components 210 (see e.g., elements 210) are circumferentially arranged in cable jacket 202 around the cable core in aAttorney Docket No.: HI24-085PCT substantially uniform arrangement. In other words, a plurality of binding components 210 are embedded within cable jacket 202 and positioned around armor layer 212 such that the binding components 210 are evenly spaced apart from each other.

[0033] In various embodiments, cable jackets 102, 202 may be multilayered. More specifically, cable jacket 202 can include a first layer and a second layer (not illustrated) wherein the second layer is an inner layer and the first layer is an outer layer that surrounds the second layer (i.e., such that the first layer and the second layer are concentric layers). In such embodiments, the first layer can be formed from a different material than the second layer. Furthermore, whether or not the first layer and the second layer are formed from different materials, binding components 210, such as yarns or a tape, are positioned between the first layer and the second layer. In various embodiments in which the cable jackets 102, 202 are multilayered, cable jacket 102 / 202 includes binding components embedded in at least one of the first layer and the second layer.

[0034] As previously noted, for particular applications and / or locations optical fiber cables are required to meet specific fire safety standards and can be rated in various categories such as flaming droplets, smoke production and acidity / corrosivity of the gases from burning. For example, the European market requires optical fiber cables to be certified with Construction Products Regulation (CPR) in terms of fire safety. A flaming droplet rating for an optical fiber cable can be determined using a flaming droplet test according to the standard EN 50399.

[0035] When there are no flaming droplets falling from vertically installed cables during the EN 50399 test, the optical fiber cable is classified as dO in the flaming droplet sub-class rating. When flaming droplets occur and the combustion of the droplets after reaching the ground lasts 10 seconds or less, the classification of the optical fiber cable is dl. In other words, during the EN 50399 test if flaming droplets fall and continue to burn from 1-10 seconds the optical fiber cable is classified as dl. If the flaming droplets have continuous combustion of greater than 10 seconds the classification of the optical fiber cable is d2. Because flaming droplets significantly increase the risk of spreading the fire from the optical fiber cables to the flooring, consumers generally require cables with a dO rating.

[0036] EXPERIMENTAL RESULTS

[0037] FIGS. 3A-4B depict a first sample 300 and a second sample 320 used to test the inventors’ hypothesis regarding the benefit of introducing additional elements to support orAttorney Docket No.: HI24-085PCT bond with a cable jacket to help retain the outer jacket on the outer cable when temperatures are elevated like a burning event. First sample 300 was formed by hot pressing a cable jacket material, specifically a low smoke zero halogen (LSZH) compound onto a glass tape. As shown in FIG. 3A, first sample 300 includes a first side 302 with a first outer surface 304. The first outer surface 304 is formed by the LSZH compound. As shown in FIG. 3B, first sample 300 includes a second side 306 with a second outer surface 308 that opposes first outer surface 304. The second outer surface 308 is formed by the glass tape.

[0038] FIGS. 4A-B depict the second sample 320. Second sample 320 was formed by hot pressing the same low smoke zero halogen (LSZH) compound as used in the first sample 300 onto steel tape, which is a common armor layer material. As shown in FIG. 4A, second sample 320 includes a first side 322 with a first outer surface 324 formed by the LSZH compound. As shown in FIG. 4B, second sample 320 includes a second side 326 with a second outer surface 328 that opposes first outer surface 324. The second outer surface 328 is formed by the steel tape.

[0039] To test first sample 300 and second sample 320, a Bunsen burner flame was applied to the first sample 300 and the second sample 320 and the dripping behavior was observed. The first sample 300, formed on the glass tape, did not form flaming droplets when the flame was applied. In contrast, the second sample 320, formed on the steel tape, was observed to continuously drip once the second sample 320 was ignited by the flame.

[0040] As shown in FIGS. 5-6, a first cable prototype 400 and a second cable prototype 420 were used to demonstrate that similar results to first sample 300 and second sample 320 would be achieved when the structure had the form of a cable. As shown in FIG. 5, first cable prototype 400 includes a cable jacket 402 having an interior surface 406 and an exterior or outer surface 404. An armor layer 408 is disposed within cable jacket 402. An outer surface 410 of armor layer 408 is bonded to cable jacket 402. First cable prototype 400 was produced with a flexible steel tube as the armor layer 408. An LSZH material known to have a high tendency of dripping in the flaming droplet test was extruded with a 2 mm thickness over the steel tube to act as the cable jacket 402. A cable core was not included in the first cable prototype 400.

[0041] As shown in FIG. 6, the second cable prototype 420 includes a cable jacket 422 having an interior surface 426 and an exterior or outer surface 424. An armor layer 428 is disposed within cable jacket 422. A support layer 432 is positioned between armor layer 428Attorney Docket No.: HI24-085PCT and cable jacket 422. Specifically, support layer 432 was positioned between an exterior surface 430 of armor layer 428 and interior surface 426 of cable jacket 422. Second cable prototype 420 was formed in the same manner as first cable protype 400 with the addition of the support layer formed from glass yams.

[0042] Table 1, below, provides a comparison of the first cable prototype 400 and the second cable prototype 420 when tested according to the EN 50399 standard. Two flaming droplet tests were performed for each of the cable prototypes 400, 420. Table 1 includes the number and category of flaming droplets observed during the EN 50399 test.

[0043] Table 1. Flaming droplet counts of the prototype cables in EN 50399 test.

[0044] From Table 1 it can be seen that first cable protype 400 without the glass yarns formed many flaming droplets during the EN 50399 tests which resulted in a dl rating. In contrast, second cable prototype 420 which included the glass yarn layer 432 between cable jacket 422 and armor layer 428 did not form any flaming droplets during the EN 50399 tests which resulted in a dO rating. First sample 300 and second cable prototype 420 demonstrate that the inclusion of the support layer between a cable jacket and armor layer significantly reduced the risk of flaming droplets. The inventors expect that an optical fiber cable with the cable core would achieve the improved flaming droplet performance demonstrated by first sample 300 in FIGS. 3A-B and second cable prototype 420. In other words, the inventors expect that optical fiber cables 100, 200 would achieve a flaming droplet count of zero and be classified as dO according to EN 50399.

[0045] The inventors further surmise that bonding components embedded in the cable jacket (see e.g., FIG. 2) and the use of other types bonding components (other yarns, tapes, threads, wires, etc.) similarly provide support for the cable to better retain the cable jacket even after the adhesion between the cable jacket and armor layer is lost, therefore reducing the risk of flaming droplets. As such the inventors expect that an optical fiber cable 200 with bonding components 210 embedded in the cable jacket would achieve the improved flamingAttorney Docket No.: HI24-085PCT droplet performance demonstrated by first sample 300 in FIGS. 3A-B and second cable prototype 420.

[0046] Unless otherwise expressly stated, it is in no way intended that any method set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method claim does not actually recite an order to be followed by its steps or it is not otherwise specifically stated in the claims or descriptions that the steps are to be limited to a specific order, it is in no way intended that any particular order be inferred. In addition, as used herein, the article "a" is intended to include one or more than one component or element, and is not intended to be construed as meaning only one.

[0047] It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit or scope of the disclosed embodiments. Since modifications, combinations, sub-combinations and variations of the disclosed embodiments incorporating the spirit and substance of the embodiments may occur to persons skilled in the art, the disclosed embodiments should be construed to include everything within the scope of the appended claims and their equivalents.

Claims

Attorney Docket No.: HI24-085PCTWhat is claimed is:

1. An optical fiber cable, comprising: a cable jacket comprising: an interior surface, the interior surface defining a central bore extending along a longitudinal axis of the optical fiber cable; and an exterior surface, the exterior surface defining an outermost surface of the optical fiber cable; a cable core disposed in the central bore, the cable core containing an optical fiber; a metal armor layer, the metal armor layer disposed in the central bore between the cable core and the interior surface; and a support layer positioned between the interior surface of the cable jacket and the metal armor layer.

2. The optical fiber cable of claim 1, wherein the support layer is at least one of a yam, thread, tape, or wire.

3. The optical fiber cable of claim 1, wherein the support layer is a fire resistant yarn.

4. The optical fiber cable of claim 1, wherein the metal armor layer is a steel tape.

5. The optical fiber cable of claim 1, wherein the optical fiber cable achieves a flaming droplet count of zero measured according to EN 50399.

6. The optical fiber cable of claim 1, wherein the cable core further comprises: a central strength member; and a plurality of buffer tubes stranded around the central strength member, wherein the optical fiber is disposed within one of the plurality of buffer tubes.

7. The optical fiber cable of claim 1, wherein the cable jacket is formed from a flame retardant material.

8. The optical fiber cable of claim 7, wherein the flame retardant material is a low smoke zero halogen material.

9. The optical fiber cable of claim 1, wherein the support layer comprises tape coupled to chopped yarns.Attorney Docket No.: HI24-085PCT10. An optical fiber cable, comprising: a cable jacket comprising: an interior surface, the interior surface defining a central bore extending along a longitudinal axis of the optical fiber cable; and an exterior surface, the exterior surface defining an outermost surface of the optical fiber cable; a cable core disposed in the central bore, the cable core containing a plurality of optical fibers; a metal armor layer, the metal armor layer disposed in the central bore between the cable core and the interior surface; and one or more binding components embedded in the cable jacket between the interior surface and the exterior surface.

11. The optical fiber cable of claim 10, wherein the one or more binding components comprise a plurality of binding components circumferentially arranged around the cable core.

12. The optical fiber cable of claim 10, wherein the one or more binding components comprise a plurality of binding components that surround the cable core.

13. The optical fiber cable of claim 10, wherein the one or more binding components are fire resistant yarns and wherein the metal armor layer is steel tape.

14. The optical fiber cable of claim 10, wherein the optical fiber cable achieves a flaming droplet classification of dO according to EN 50399.

15. The optical fiber cable of claim 10, wherein the one or more binding components include at least two binding components.

16. The optical fiber cable of claim 10, wherein the one or more binding components embedded within the cable jacket are chopped yams.

17. The optical fiber cable of claim 10, wherein the cable core further comprises: a central strength member; and a plurality of buffer tubes stranded around the central strength member;Attorney Docket No.: HI24-085PCT wherein at least one optical fiber of the plurality of optical fibers is disposed within each one of the plurality of buffer tubes.

18. An optical fiber cable, comprising: a cable core comprising at least one optical fiber; a flame retardant cable jacket surrounding the cable core, wherein the cable jacket comprises: an interior surface, the interior surface defining a central bore extending along a length of the optical fiber cable; and an exterior surface; a metal armor layer, the metal armor layer surrounded by the cable jacket; and a support layer or binding component positioned between the exterior surface of the cable jacket and the metal armor layer.

19. The optical fiber cable of claim 18, wherein the support layer or binding component comprises at least one of a fire resistant yam, thread, tape, and wire.

20. The optical fiber cable of claim 18, wherein the metal armor layer is one of steel tape and aluminum tape.

21. The optical fiber cable of claim 18, wherein the flame retardant cable jacket is formed from a low smoke zero halogen material.

22. The optical fiber cable of claim 18, wherein the flame retardant cable jacket is a multilayer cable jacket comprising: a first layer defining an outermost surface of the cable jacket; and a second layer surrounded by the first layer.

23. The optical fiber cable of claim 22, further comprising a second support layer positioned between the first layer of the cable jacket and the second layer of the cable jacket.

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