Patent Publication Number: US-7905296-B2

Title: Methods and apparatus for controlling hazardous and/or flammable materials

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application: 
     is a continuation of U.S. Nonprovisional patent application Ser. No. 10/728,223, filed on Dec. 3, 2003 now abandoned, which 
     claims the benefit of U.S. Provisional Patent Application No. 60/430,912, filed Dec. 3, 2002; 
     is a continuation-in-part of U.S. Nonprovisional patent application Ser. No. 09/920,179, filed Aug. 1, 2001 now abandoned; and 
     is a continuation-in-part of U.S. Nonprovisional patent application Ser. No. 10/443,302, filed May 21, 2003; 
     and incorporates the disclosure of each application by reference. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to methods and apparatus for controlling hazardous and/or flammable materials and the effects of such materials. 
     BACKGROUND OF THE INVENTION 
     Flammable and otherwise hazardous materials play an important role in the everyday lives of most people. Most people encounter flammable materials, such as gasoline, engine oil, and natural gas, and other hazardous materials, such as battery acid and concentrated detergents, without danger. Because the unsafe materials are contained, they typically present no problem for those that are nearby. 
     When the unsafe materials become uncontained, however, the materials can injure or kill, such as when the container is damaged and the material escapes. For example, hundreds of thousands of vehicular accidents occur each year on American highways. Many accident-related fire events occur when the region of the vehicle containing the fuel tank is impacted in an accident, spilling the fuel contents from the tank in the form of a spray, stream, and eventual pool around the vehicle. The highly ignitable spray mist generated upon impact may be exposed to ignition energy from sparks generated from vehicle deformation on impact for only a fraction of a second. This duration, however, may be long enough to ignite the fuel mist into a possible explosion, or more likely a fireball that ignites a developing pool of fuel surrounding the vehicle and create a more serious threat. 
     In many cases, the threat of ignition and resultant flame spread only exists for the instant that the sparks from the impact event remain. These events have been noted particularly on several recent automotive and truck designs that were hypothesized, due to tank placement and structural design, to have potentially higher rates of incidences of such events. These high profile examples often lead to spectacular fire events and the higher rates of burn injuries and fatalities when they occur, and have resulted in national discussions on how to prevent their continued occurrence. 
     Unfortunately, most fire protection technologies are impractical for general highway vehicle or other consumer use, due to cost, complexity, reliability problems, and substantial weight increases. As a result, little has been done to prevent such events in the future. The military, however, has confronted similar events that occur in combat scenarios. In particular, military aircraft that are impacted by anti-aircraft projectiles can develop fires in adjoining bays adjacent to fuel tanks onboard the aircraft. The fuel leaking or spraying from a penetrated tank encounters ignition sources, such as burning incendiary particles deposited by the projectile in the adjoining bay, with resultant fires threatening the interior of the aircraft. Many aircraft losses in combat have been attributed to such events. 
     As a result, technologies have been developed in recent decades to prevent or suppress such events for newer combat aircraft. One approach to aircraft fire protection uses passive systems. These systems are typically some form of structure that requires no electrical power or other artificial monitoring. These systems function by being impinged directly by the explosion or fire event. They typically provide explosion protection inside the fuel tank or in surrounding compartments around the fuel tank. One of the earliest and most successful variants was the use of flexible reticulated foam in fuel tanks to mitigate explosions. This concept was extensively used successfully in the latter stages of the Vietnam War and became a fixture on many modern era aircraft. 
     The British military developed several advanced concepts in the early 1970s. These included forming reticulated foam into balls to fill various compartments adjacent to fuel tanks in aircraft (U.K. Patents 1,380,420, 1,445,832, and 1,454,492) that could be coated with substances that swell upon heating to cut off air supply to the fire, and filled with various gaseous and powder extinguishing agents to provide extra fire extinguishing in addition to fire mitigation. The main advantages of such concepts were ease of installation, high reliability due to lack of sophisticated electronics and other devices, and competitive weight penalties in comparison to active fire suppression systems, such as gaseous fire extinguishing and detection systems, with the trade-off depending upon the compartment volume and configuration. 
     Other passive protection systems use fire suppressants embedded into rigid or semi-rigid panels mounted onto the wall of the fuel tank adjoining and facing an adjacent bay. The panels, when impacted by a projectile penetrating through the aircraft, would rupture locally and release a portion of suppressant into the adjacent bay, extinguishing the beginnings of fuel spray from the damaged fuel tank entering the bay and igniting, or rendering the fuel vapors inert against ignition when coming into contact with the deposited incendiary particles. The panels were developed and demonstrated with gaseous extinguishing agents and various powders (U.K. Patents 1,454,493 and 1,547,568). The panels took the form of hollow panels with cylinders or sachets of suppressant inserted, or balls or sheets of reticulated foam (sometimes sealed in bags with a pressurized gaseous suppressant). 
     All of these variations showed some level of performance enhancement for a given system volume or weight, but could be offset by increased complexity or increased material, assembly, or installation cost. The most common and simple variations were thin panels with a hexagonal honeycomb sandwich material of kraft paper, aluminum, or Nomex, filled with a fire extinguishing powder and covered with a thin sheet on both faces of aluminum foil, composite fibers, or other materials. These devices were described as powder panels or powder packs. 
     The powder panels were demonstrated to effectively protect against many large ballistic incendiary threats with as little as 0.1 inch total thickness and 0.2-0.6 pounds mass per square foot. Other threats and conditions could require much thicker, heavier, systems if they worked at all. Some limitations in performance were seen against small threats that limited rupture damage to the panel and as a result limited the amount of powder suppressant released to extinguish the fire. 
     Variations of this concept were investigated for use against ballistic impacts in armored vehicles (U.S. Pat. Nos. 3,930,541 and 4,132,271), although powders were primarily limited for use in engine compartments due to the inhalation difficulties with crew members, and gaseous suppressant filled panels were used in the crew compartment. Later fine tuning was made including adding spall shields to prevent spallation damage from the panels to crew members. 
     Since these systems require ballistic impact to function, their utility and consideration was limited to combat-induced ballistic impact events; they offer no protection against gradual fuel system leakage and ignition due to ordinary fuel system failures. Further, such systems do not provide protection against other types of threats or problems. For example, such systems do not provide protection in other fire scenarios, such as collisions impacting and fracturing fuel tank valves and their connectors, particularly for alternate fueled vehicles. Additional flammable fluid reservoirs, such as brake master cylinders and fuel pumps, contain sufficient flammable fluid to pose a threat to vehicle occupants or the vehicle itself, and their small, bulky shapes provide difficulties in providing protection. Other areas of a vehicle, such as the vehicle&#39;s engine compartment hood, exhibit damage in front end crashes, and may cause the release of flammable or otherwise hazardous materials. Further, some components, such as the oil pan, may rupture and discharge flammable fluids due to the internal destruction of the engine, which is typically accompanied by the fracturing and penetration of the connecting rods through the oil pan. This scenario is very common in automobile racing in addition to highway occurrences. 
     SUMMARY OF THE INVENTION 
     A hazard control system according to various aspects of the present invention comprises a housing configured to contain a control material and deliver the control material to neutralize a hazard in response to a trigger event. In one embodiment, the control material is an extinguishant for retarding fire. The housing contains the extinguishant and includes at least one surface configured to rupture in response to a trigger event, such as an impact. The housing may also include a surface configured to substantially mate with a surface of a vehicle, such as a fuel tank surface. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete understanding of the present invention may be derived by referring to the detailed description when considered in connection with the following illustrative figures. In the following figures, like reference numbers refer to similar elements and steps. 
         FIG. 1  is an illustration of a hazard control system having a honeycomb core; 
         FIG. 2  is a cross-section view of the hazard control system of  FIG. 1 ; 
         FIG. 3  is an illustration of a housing configured for a fuel tank. 
         FIG. 4  is an illustration of a hazard control system having multiple panels around a fuel tank. 
         FIG. 5  is an illustration of a crash incident involving impact between two motor vehicles, one of which is equipped with a hazard control system; 
         FIG. 6  is a partial cutaway view of a hazard control system having multiple parallel, isolated channels; 
         FIG. 7  is a cross-section view of the hazard control system of  FIG. 6 ; 
         FIG. 8  is an illustration of an end cap; 
         FIG. 9  is an illustration of hazard control system having shattering a face sheet; 
         FIG. 10A-B  are top and cross-section views, respectively, of a hazard control system having multiple perpendicular, interconnected channels; 
         FIG. 11  is a cross-section view of a hazard control system having partitions integrated into a face sheet and bonded to another face sheet by an adhesive; 
         FIG. 12  is an illustration of a hazard control system having multiple interconnected compartments; 
         FIGS. 13A-B  are perspective and top illustrations, respectively, of a hazard control system conformed to the shape of a fuel tank; 
         FIGS. 14A-C  are illustrations of a hazard control system being cut to a desired size; 
         FIG. 15  is a partial cutaway view of a fuel pump shrouded with a hazard control system; 
         FIG. 16  is a view of a fluid reservoir fitting surrounded by a hazard control system at the location of connection of the reservoir to the fluid line; 
         FIG. 17  is a view of a hazard control system fitted for a connector of two fluid line fittings; 
         FIG. 18  is an illustration of a hazard control system adapted for an oil pan of an internal combustion engine pierced by a connecting rod; 
         FIG. 19  is an illustration of a vehicle front-end collision, with the engine compartment hood deforming and activating the hazard control system; 
         FIG. 20  is a cross-section view of a liquid reservoir having a hazard control system and a pool fire impinging on a liquid reservoir; and 
         FIG. 21  is a cross-section view of a damaged battery enclosure having an activated hazard control system. 
     
    
    
     Elements and steps in the figures are illustrated for simplicity and clarity and have not necessarily been rendered according to any particular sequence. For example, steps that may be performed concurrently or in different order are illustrated in the figures to help to improve understanding of embodiments of the present invention. 
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     The present invention is described partly in terms of functional components and various processing steps. Such functional components may be realized by any number of components configured to perform the specified functions and achieve the various results. For example, the present invention may employ various elements, materials, suppressants, neutralizing agents, and the like, which may carry out a variety of functions. In addition, the present invention may be practiced in conjunction with any number of applications, environments, hazardous materials, and trigger events, and the systems described are merely exemplary applications for the invention. Further, the present invention may employ any number of conventional techniques for manufacturing, assembling, mounting, and the like. 
     Referring now to  FIGS. 1 and 2 , a hazard control system  100  for controlling hazardous and/or flammable materials according to various aspects of the present invention may be implemented in conjunction with a housing  102  containing a control material  104 . The housing  102  is configured to contain the control material  104  and facilitate dispersal of the control material  104  in response to a trigger event, especially relatively large quantities of control material  104  for relatively large-scale events such as an impact, exposure to heat, or detection of a hazard. The control material  104  comprises one or more materials for controlling a hazard. 
     The housing  102  may comprise any suitable apparatus for containing the control material  104  and facilitating dispersal of the control material  104  in response to the trigger event. For example, the housing  102  may comprise a container configured to shatter, explode, or otherwise deteriorate, either entirely or in part, upon impact to release the control material  104 . In various embodiments, the housing  102  may comprise a rigid structure, a semi-rigid structure, a membrane, or a bladder. The housing  102  may be comprised of any suitable materials, for example glass, ceramic, or plastic that is designed to shatter upon impact. Further, the housing  102  may be configured to promote dispersal of the control material  104 , for example by scoring the housing  102  to promote fracturing of the scored surface in the event of an impact. The housing  102  may include additional mechanisms for promoting dispersal of the control material  104 , such as one or more spring mechanisms, such as a leaf spring, compressed coil spring, a flat spring, an expandable material, configured to enhance the expansion of the housing  102  when the housing  102  is weakened or fractured by the trigger event. In one embodiment, multiple channels formed in the housing  102  include spring mechanisms to biased against a surface of the housing  102  to be impacted. 
     In the present embodiment, the housing  102  suitably comprises two face sheets  106  sandwiching the control material  104 . The face sheets  106  maintain the control material  104  in position, and may comprise any suitable configuration, such as a rigid sheet, a flexible cover, a flexible bladder, or any other appropriate system for maintaining the control material  104  in a selected position. Further, the face sheets  106  may comprise any appropriate materials, including cellulosic material such as styrene, paper, glass, plastic, metal, ceramic, aluminum, nylon, glass fabric, fiberglass/epoxy, Kevlar, graphite tape, or a composite or combination of such materials. The face sheets  106  are suitably configured to react to a trigger event, such as an impact, a thermal event such as exposure to heat, or an optical event such as exposure to particular radiation. In the present embodiment, the face sheets  106  are suitably configured to substantially completely shatter or otherwise rupture to promote total release of the control material  104 . The housing  102  may also comprise malleable materials, so the housing  102  may be shaped and bent to fit various configurations. In the present embodiment, the face sheets  106  are rectangular sheets constructed of a lightweight and cost effective material, such as glass, ceramic, acrylic, and/or epoxy. 
     The face sheets  106  are suitably mounted on a frame  108  to support the face sheets  106 . The frame  108  may comprise any suitable structure, such as a rigid structure joined to the face sheets  106 , an adhesive material like a caulk between the face sheets  106 , or a rigid spacer. In an alternative embodiment, the frame  108  may be omitted and the face sheets  106  may be otherwise configured to maintain the position of the control material  104 . For example, the ends of the face sheets  106  may be taped adhesively, glued, or crimped, or the face sheets  106  may be formed as a single unit, such as using blow molding, vacuum forming, or thermoforming to form the housing  102 . 
     In the present embodiment, the frame  108  is configured to support the face sheets  106  and maintain the control material  104  in position. For example, the frame  108  suitably comprises a rigid structure having the same shape as the face sheets  106  and bonded to the face sheets  106 . Thus, in the present embodiment, the frame  108  comprises a rigid rectangular frame  108  configured to support the face sheets  106 . In addition, the face sheets  106  may be connected to the frame  108  in any suitable manner, for example using fasteners or a bonding agent. In the present embodiment, the face sheets  106  are bonded using an epoxy  110  or a similar adhesive. Other variations may be used to bond the face sheets  106  to the frame  108 , such as hot glues and other chemical adhesives. 
     The housing  102  may also include a core  112  configured to separate the control material  104  into multiple compartments. The core  112  may also maintain a desired space between the face sheets  106  and support the face sheets  106 . The core  112  may be configured in any suitable manner. In the present embodiment, the core  112  may be configured in a honeycomb configuration to form individual compartments. In addition, the core  112  may comprise any appropriate materials, such as lightweight, rigid materials. In the present embodiment, the core  112  comprises aluminum or Nomex. 
     The housing  102  contains the control material  104 . In the present embodiment, the control material  104  is contained in the compartments formed by the core  112 . The control material  104  may comprise one or more suitable materials for neutralizing a particular hazard, such as a fire, acid spill, or noxious gas release. For example, to extinguish a fire, the control material  104  may comprise a fire suppressant, such as monoammonium phosphate, mixed with an appropriate desiccant and/or flow enhancer such as a 1% concentration of micronized fumed silica. Alternatively, the suppressant may comprise sodium bicarbonate, potassium bicarbonate, potassium carbonate, urea-based powders, potassium dawsonite, ammonium polyphosphate, monoammonium phosphate, potassium iodide, or other powder suppressants or mixtures, or liquid or gaseous agents, such as water, nitrogen, carbon dioxide, argon, iodotrifluoromethane, heptafluoropropane, pentafluoroethane, or other gaseous agents or mixtures. 
     The compartments of the core  112  are suitably totally filled to capacity, though some settling may occur after construction and installation, leaving some void space in the core  112 . If the compartments are not completely full, the control material  104  may be supplemented with a filler, such as a neutral, non-burning substance to occupy internal volume. In the present embodiment, the filler is configured to cover a large area while adding little weight. The filler may comprise, for example, silica dessicant, glass or plastic microspheres which may be filled with the control material  104  or remain empty, or other suitable lightweight material. 
     In addition, the control material  104  may be enhanced to facilitate dispersal and/or react to the trigger event. For example, the control material  104  may be pressurized, for example with air, a gaseous control material  104 , or other fluid to enhance dispersal of the control material  104 . Further, the control material  104  may respond directly to the trigger event. For example, the control material  104  may include an optically reactive, thermally reactive, or impact reactive material that causes the control material  104  to expand or otherwise deploy. 
     The control material  104  may also be supplemented with or include a propellant to propel the control material  104  out of the housing  102  to enhance delivery. For example, the control material  104  may be supplemented containers of gas, such as ambient or pressurized air or a fire suppressant gas, that when compressed by the impact, burst and provide a gust of air to help disperse the control material  104 . The containers may comprise any suitable containers, such as enclosed tubes or balls of thin plastic or other suitable material. Alternatively, the propellant may comprise a material that, when exposed to air, generates an expanding volume of gas to propel the control material  104 . The propellant may also comprise a fire suppressant material, such as carbon dioxide. Alternatively, the propellant may include different areas of the housing  102  that may contain separate materials. When the materials react to the trigger event, such as in response to heat or by mixing following rupture of the housing  102 , the materials may react to generate a propelling gas and, in some embodiments, a supplemental fire suppressant. For example, the materials may comprise acetic acid and a sodium bicarbonate control material  104 , which produces carbon dioxide when mixed. Alternatively, the material may comprise carbonic acid, which reacts to heat, such as due to a fire, by decomposing to water and carbon dioxide. Other materials may be used that create carbon dioxide and water when mixed, such as calcium carbonate and hydrochloric acid, or sodium carbonate and dilute sulfuric acid. Yet other materials may produce a fire suppressant foaming agent. For example, the supplementary material or control material  104  may comprise sodium bicarbonate powder with a licorice additive, which mixed with aluminum sulfate will make a sticky, aluminum hydroxide foam. Other materials may comprise compositions of nitrogen triiodide or nitrogen tribromide powders or solids, possibly mixed with stabilizing binders, which when impacted convert to nitrogen gas and fire suppressing iodine or bromine gas. 
     The hazard control system  100  may be attached to or integrated into a hazard source, such as a fuel tank or other hazardous material storage unit in a vehicle, such as a car, bus, truck, aircraft, racing car, police car or van, military vehicle or craft, racing boat, rail car, tractor trailer, or heavy equipment. For example, referring to  FIGS. 5 and 9 , a highway vehicle  510  is suitably equipped with the hazard control system  100  by attaching the hazard control system  100  to the vehicle&#39;s fuel tank  514 . When the highway vehicle  510  is impacted by a colliding vehicle  512 , the exterior of the highway vehicle  510  and the fuel tank  514  deform, also deforming hazard control system  100  attached to the fuel tank  514 . When deformed and ruptured, the hazard control system  100  releases the control material  104 , such as a suppressant powder  516  comprising monoammonium phosphate, which tends to neutralize the area around the damaged and potentially leaking fuel tank  514  to inhibit fire initiation. The hazard control system  100  may be configured for any suitable environment or application, however, such walls that may be subject to impact, heat, or other hazard, exterior of buildings, near airport runways, within or upon hazardous material transports, and the like. 
     The hazard control system  100  may be configured in any suitable manner for a particular application, such as to enhance or direct dispersal of the control material  104 , facilitate adaptation to multiple applications, reduce weight and/or cost, fit to particular objects, mitigate one or more different hazards, and the like. Referring to  FIGS. 6  and  7 , an alternative housing  102  includes multiple channels  610 . The channels  610  are suitably configured to contain the control material  104  for release. The channels  610  may be configured in any suitable manner and formed by any appropriate structure. For example, the channels  610  may be formed by the core  112  or on one or more of the face sheets  106 , the frame  108 , and/or other parts of the housing  102 . 
     In the present embodiment, the channels  610  are formed by raised partitions formed on an interior surface of at least one of the face sheets  106 . Consequently, no core  112  is included. Alternatively, the housing  102  may include the core  112  to form the channels  610 , and the frame  108  may also include structure, such as protruding partitions or other suitable structure, to form all or part of the channels  610 . 
     In addition, the channels  610  may be formed in any appropriate manner to maintain the position of the control material  104 , facilitate dispersal of the control material  104  upon occurrence of the trigger event, provide ease of manufacturing and/or installation, or any other purpose. In the present embodiment, the channels  610  are configured to form individual parallel channels  610 . Alternatively, the channels  610  may be configured in a serpentine pattern, diagonal channels  610 , a combination of diagonal, horizontal, vertical, and/or otherwise oriented channels  610 . 
     Further, the channels  610  may run in any suitable direction, and may be interconnected. For example, referring to  FIGS. 10A-B , the channels  610  may run horizontally and vertically through the housing  102 . The channels  610  are defined by partitions  1010 . The partitions  1010  may also maintain separation between the face sheets  106 , and may also provide attachment points for connecting the two face sheets  106  together, for example using an adhesive, to form the housing  102 . The partitions  1010  may comprise any appropriate configuration, such as square, circular, or rectangular partitions, and may be formed in any suitable manner, such as by collectively forming a separate core  112  or by being formed on or attached to one or more face sheets  106 . Such partitions  1010  may also be included in configurations using individual channels or compartments, such as channels or compartments that are hermetically sealed from one another, for example to provide additional rigidity. 
     The housing  102  may also include structural components to provide rigidity, such as ribs formed in the housing  102 . In addition, the face sheets  106  may be joined by an adhesive  1114  that has limited bond strength, sufficient only for normal operational environments. The limited strength of the adhesive suitably provides minimal impedance to crack propagation of the second face sheet  1112 , facilitating separation of the second face sheet  1112  (in its entirety or in pieces) from the partitions  1010 . 
     To enclose the housing  102 , the housing  102  edges may be sealed, for example using tape or caulk. Referring to  FIGS. 6 and 8 , the housing  102  of the present embodiment is closed along an edge  610  with an end cap  810 . The end cap  810  may be connected to the face sheets  106  in any suitable manner, for example by being snapped, glued, adhered, fastened, or otherwise attached to the edge  610 . The end cap  810  may comprise any suitable material, such as rubber or other resilient material, to be pressed into the edge  610  of the housing  102 . 
     The housing  102  may include any appropriate materials to facilitate response to the trigger event, provide manufacturing efficiency, reduce weight, or satisfy any other appropriate criteria. For example, referring to  FIG. 11 , the housing  102  may be configured to aid in its full discharge of extinguishing chemical in response to a trigger event including an impact. To facilitate greater breakup of the housing  102  upon impact, first face sheet  1110  and partitions  1010  may be formed of a first material that is relatively inexpensive and strong, such as in one piece of polycarbonate, and the second face sheet  1112  may comprise a material more prone to total breakage when impacted, such as acrylic or styrene. Alternatively, the housing  102  may be completely formed of a single material, such as acrylic, styrene, styrenics polymer, polyphenylene, polypropylene, and/or polycarbonate. In the present embodiment, the housing  102  comprises a material having desired brittleness and durability and demonstrating favorable fabrication features, such as a plastic, alloy, ceramic, composite, metal, fiber, and/or glass. The particular material and configuration may be selected according to the particular application. In one embodiment, the housing material may be treated to improve the various characteristics of the housing material. For example, the housing  102  may comprise a first material having desirable brittleness, such as acrylic, styrene, styrenics polymer, or the like, and a second polymer, such as a fiber, polycarbonate, or another type of acrylic, styrene, styrenics polymer, or the like, configured to improve the characteristics of the first material, such as the ductility to improve the workability of the material. For example, the housing material may comprise a first styrenics polymer having a high brittleness and a second styrenics polymer mixed with the first to lower the melting temperature of the overall housing material and otherwise improve the manufacturing characteristics of the material. The ratio of the first material to the second material may be selected according to the desired characteristics of the housing  102 . For a high brittleness material, the second material may comprise only a small amount, such as about 10% by weight or less, of the overall material. For improved ductility during manufacturing, the second material may comprise a larger amount, such as about 50% or more of the overall material. In one embodiment, the first brittle material comprises about 60-80% of the overall material, and the second material comprises about 20-40% of the overall material. A suitable material may comprise approximately 70% of the first material and about 30% of the second material. 
     An alternative embodiment of the housing  102  includes multiple compartments for containing the control material  104 . Each compartment may be fully enclosed or connected to one or more other compartments. For example, each compartment may be fully enclosed and individually filled with the control material  104 . Alternatively, a compartment may be connected to another compartment so that both compartments may be filled by accessing a single compartment. Using multiple compartments suitably facilitates cutting the housing  102  to a selected size. 
     For example, referring now to  FIG. 12 , an alternative housing  102  includes multiple compartments  1210  containing the control material  104 . The compartments  1210  may have any appropriate shape or size, such as approximately three inch by five inch rectangles. The housing  102  may form the compartments  1210  in any suitable manner. In addition, the compartments  1210  may be oriented in any manner, such as in rows parallel to an axis of the housing  102  or one or more of the face sheets  106 . 
     In the present embodiment, the housing  102  comprises two face sheets  106 A-B. At least one of the face sheets  106 A includes multiple indentations to form the compartments  1210 . For example, the second face sheet  106 B may be flat and the first face sheet  106 A may be configured to include multiple indentations in the form of the compartments  1210 . The compartments  1210  are suitably formed in rows parallel to a longitudinal axis of the face sheets  106 . 
     The two face sheets  106  are joined in any suitable manner so that the second face sheet  106 B covers the indentations in the first face sheet  106 A to form the compartments  1210 . The compartments  1210  may, however, be formed in any suitable manner, such as by indentations in the second face sheet  103 B, compartments formed by the core  112 , independent bladders, a quilted bladder having multiple pockets, and the like. 
     The compartments  1210  of the present embodiment are suitably connected to allow control material  104  to flow between the interconnected compartments  1210 . The compartments  1210  may be interconnected in any suitable manner, such as via openings  1212  formed along one or more sides or other surfaces of the compartments  1210 . Further, the openings  1212  may be connected in any suitable manner, for example via one or more ducts  1214  connecting the openings  1212 . The connections between the compartments  1210  may be implemented in any appropriate manner, such as using tubes attached to the compartments  1210 , indentations in one or both of the face sheets  106 , inclusion of a core  112  including the ducts  1214 , and the like. In the present embodiment, the ducts  1214  are formed by indentations formed in the first face sheet  106 A adjacent the indentations used to form the compartments  1210 . 
     In addition, the housing  102  may include any other desired structures to lend desired characteristics to the housing  102 , such as to add stiffness, provide mounting surfaces or mechanisms, and the like. For example, in the present embodiment, the first face sheet  106 A may include rectangular indentations  1216  formed between the duct indentations  1214  to reduce the surface-to-surface contact between the face sheets  106  and promote crack propagation. 
     In the present embodiment, each compartment  1210  along two edges of the housing  102  has at least one opening  1212  in one side which is connected to a duct  1214 . Each compartment  1210  in the interior of the housing  102  and along the other two edges of the housing  102  has two openings  1212  on opposite sides of the compartment  1210 . The openings  1212  are connected to the openings  1212  of the other compartments  1210  via the ducts  1214  to form connected compartments. Consequently, the control material  104  may move between the compartments  1210  through the openings  1212  and ducts  1214 . Referring again to  FIG. 12 , each duct  1214  comprises at least one wall that is distinct from the wall of any other duct and/or connected compartment  1210 . Additionally, the perimeter and/or area formed by each duct  1214  is less than the perimeter and/or area formed by an adjacent connected compartment  1210 . 
     The hazard control system  100  may be configured for a selected environment, a selected hazard, and/or a selected trigger event. For example, the hazard control system  100  may be adapted for use with vehicle fuel tanks, storage tanks, fuel or chemical transfer lines, connectors, valves, and other components, oil containers and oil pans, battery compartments, engine compartments, or other applications. In addition, the hazard control system  100  may be configured to control flammable materials, toxic materials, caustic or corrosive materials, or other harmful materials. Further, the hazard control system  100  may be configured to respond to any suitable trigger event, such as an impact, exposure to heat, exposure to a particular substance, or detection of a hazardous condition. 
     For example, the hazard control system  100  may be specifically configured for particular applications by shaping the housing  102  to conform to a selected surface. For example, referring to  FIG. 3 , an exemplary housing  102  substantially conforms to the exterior of the fuel tank. Clearance holes  310  accommodate fittings and exterior connections to the fuel tank. Grommets may also be installed in the clearance holes  310 . 
     Referring to  FIGS. 13A-B , an alternative embodiment of the housing  102  may be configured to conform to the interior or exterior shape of a fuel tank  1310  for police vehicle, such as a Ford Crown Victoria Police Interceptor, a bus, or a motorsports car. In the present embodiment, the first face sheet  106 A has an outer surface that is configured to substantially mate with an exterior surface of the relevant fuel tank  1310 , such as the top, rear, front, or side of the fuel tank  1310 . The outer surface of the second face sheet  106 B is configured to conform to the space requirements of the vehicle, such as to fit within the fuel tank area or the trunk of the vehicle. 
     The housing  102  may be configured in any suitable manner to contain the control material  104 , such as a fire suppressant, and shatter upon impact to release the control material  104 . In the present embodiment, the housing  102  includes partitions formed in at least one of the face sheets  106  to form the compartments  1210  and suitably the ducts to interconnect the compartments  1210  as shown in  FIG. 12 . The face sheets  106  are suitably bonded together using an adhesive. 
     Referring to  FIG. 4 , an alternative hazard control system  100  according to various aspects of the present invention comprises multiple housings  102 . Each housing  102  conforms to the respective outer surfaces of the fuel tank  514 , and may be attached to the fuel tank  514  in any suitable manner, such as via an adhesive. Alternatively, the hazard control system  100  may comprise a single structure or multiple interconnected structures surrounding the exterior or disposed within the interior of the fuel tank  514 . 
     In an alternative embodiment, the hazard control system  100  may be configured for adaptation to any particular application using one of more housings  102 . For example, multiple housings  102  may be attached to a fuel tank  514  or other structure to facilitate hazard mitigation. In addition, the housings  102  may be cut to a selected size and/or shape for a particular application. 
     For example, referring again to  FIG. 12 , the housing  102  may be cut to an approximate desired width and length. Any compartments  1210  that are opened due to the cutting may be emptied of control material  104 . Referring to  FIGS. 14A-C , a housing  102  is configured to be cut to a desired width  1412  and length  1410 . To cut the width, the bottom portion may be cut away ( FIG. 14B ). Although the cutting opens a series of compartments, several other compartments remain intact. Thus, the hazard control system  100  remains functional. 
     To cut the length, a length of the housing  102  may be cut away ( FIG. 14C ). By cutting the length, multiple compartments may be opened, which may remain empty. The ducts leading to the empty compartments may then be closed, for example using putty, tape, caulk, epoxy, a resilient plug, or other mechanism. Thus, the control material  104  remains within several compartments of the housing  102 . In the present embodiment, the compartment spacings are configured to permit cutting between the cells, to leave a sealing flange, such that only fill ports connecting the cells in each row remain exposed for filling. Consequently, the housing  102  may be cut after being filled with the control material  104  to reduce unfilled panel material around the perimeter. 
     The hazard control system  100  may be attached to or associated with a hazard source in any appropriate manner. In various applications, the hazard control system  100  may be placed adjacent to or above the hazard source. Alternatively, the hazard control system  100  may be attached to or abut the hazard source. Any appropriate system or mechanism may fix the hazard control system  100  in position. For example, the housing  102  may be adhesively attached directly to the fuel tank  514 , such as via a peel-and-stick adhesive tape. The housing  102  may also be attached to other areas in proximity of the fuel tank  514 , such as the inside of the vehicle body panels, and can be attached by any other suitable mechanism, such as tape, straps, rivets, clips, hook-and-loop fasteners, or other fasteners. 
     In another embodiment, the hazard control system  100  may be adapted for a particular component that may be susceptible to causing a hazard. For example, referring to  FIG. 15 , the housing  102  is adapted to conform to a fuel pump  1510 , such as for an internal combustion engine. The housing  102  is suitably configured to fit over the fuel pump  1510 , such as by vacuum forming, blow molding, or other suitable process. The housing  102  may be connected to the fuel pump  1510 , such as via a press fit, outer band clamps, or internal adhesive. The hazard control system  100  may also include a separate end plate  1512  that is attached (adhesively or otherwise) to the end of the housing  102  near the outer end of the fuel pump  1510 , particularly if simple cylindrical geometries are applicable. The housing  102  may be configured according to any appropriate design to facilitate dispersal of the control material  104  in response to the trigger event. In one embodiment, the housing  102  is configured with channels  610  between thin double-walled plastic face sheets  106 . The control material  104  is disposed within the channels  610  or compartments  1210  of the housing  102 . 
     The housing  102  is suitably configured such that when the fuel pump  1510  is impacted sufficiently (such as in an accident) to break off or partially disconnect the fuel pump  1510  from the engine, facilitating the discharge of its flammable fluid contents and its subsequent ignition, the housing  102  should also break apart due to the same impact, releasing a cloud of suppressant around the region of fluid discharge to mitigate ignition and any resultant fires. The hazard control system  100  may be similarly adapted for other reservoirs and components, including superchargers and turbochargers, power steering pumps, vapor canisters, brake master cylinders, oil pumps, washer fluid reservoirs, fuel pressure reduction valves, and other valves attached to fluid vessels such as those on compressed natural gas (CNG) tanks, liquefied petroleum gas tanks (LPG), hydrogen tanks, and other alternate fueled vehicles. 
     The hazard control system  100  may also be adapted to fluid lines and connectors to control hazards in the event of the trigger event. For example, referring to  FIG. 16 , the hazard control system  100  is configured for a connection point of a fluid line  1612  to a fluid reservoir  1614 . The hazard control system  100  suitably includes a housing  102  in the form of a ring  1610  or similar shape that covers the attachment point of the fluid line  1612  and reservoir  1614  and attached to the surrounding face of the reservoir  1614 . The ring  1610  has sufficient internal volume to contain enough control material  104  for a particular hazard, such as a dry chemical suppressant to prevent the ignition of any fluids released by the separation of line  1612  and reservoir  1614 , for example due to an accident. 
     The present embodiment also suitably includes a washer  1616  attached to the fluid line  1612 . In addition, scored fracture lines  1618  may also be added to the outer faces of the ring  1610 . If an event occurs that results in the pulling of the fluid line  1612  sufficiently as to separate it from the reservoir  1614  (such as due to a collision), then the washer  1616  (attached to the fluid line  1612 ) pulls through the ring  1610 , rupturing the ring  1610  and dispersing the control material  104  around the surrounding area to suppress the hazard, such as ignition of fluid discharging from the disconnected line in the local area. 
     The hazard control system  100  may be further configured for controlling hazards at the coupling of two fluid lines  1706 . For example, referring to  FIG. 17 , the housing  102  comprises two disks  1708 A-B that are attached to each other, such as by use of an adhesive  1710 . The outer surfaces of the disks form cavity  1712  to accommodate a coupling  1714  connecting together two fluid lines  1706 . A flange  1716  may be attached to each fuel line  1706 , outside of the coupling  1714  but captured within the disks  1708 A-B when they are attached together. The outer faces of the disks  1708 A-B may also have their surfaces scored radially from their fuel line openings to assist in panel breakup. 
     If the two ends of the fluid line  1706  are pulled apart (such as due to a collision) and disconnect at the site of the coupling  1714 , the flange  1716  of either fluid line  1706  (or both) pulls through the panel disks  1708 A-B and shatters them and the control material  104  is released at the same time to inhibit the relevant hazard, such as the ignition of any fluids discharged from the disconnecting lines. The adhesive force between the faces of the disks  1708 A-B is designed to be stronger than the force required to fracture either disk  1708 A-B by a flange  1716  on either line, to assure that disk fracturing occurs. 
     In another alternative embodiment, the hazard control system  100  may be adapted for controlling a hazard in the event of damage to an oil pan. Referring to  FIG. 18 , the hazard control system  100  includes a housing  102  over an oil pan  1810 , suitably formed as a tightly fitting housing  102  which has been molded from liquid plastic or formed from double wall material, a rectangular formation of flat double-wall panels in the general shape of the oil pan  1810 , or other suitable configuration. The housing  102  is attached to the oil pan  1810  by any appropriate mechanism and contains an appropriate control material  104 . The housing  102  may extend over the lower engine block as well, in the event of engine failure in other areas. The housing  102  may also be placed as a sheet or curved panel some distance away from the oil pan  1810 , but within proximity of the oil pan  1810  sufficient to assure its rupture from the discharged engine components. If the engine to which the oil pan  1810  is attached breaks a connecting rod  1812  and propels it through the oil pan  1810 , discharging oil and fuel, the housing  102  also tends to break and discharge the control material  104 , for example as a cloud of fire suppressant to prevent the ignition of the released oil and fuel near the exhaust manifold or other ignition sources. 
     In another embodiment, the hazard control system  100  may be configured for controlling hazards in an engine compartment. The hazard control system  100  is suitably configured to diminish a hazard in the event the engine compartment is damaged or another trigger event occurs. For example, the hazard control system  100  may be configured to inhibit fire in the event the engine compartment of a convention automobile is damaged, such as in a front-end collision. Referring to  FIG. 19 , an exemplary hazard control system  100  includes a housing  102  attached to or integrated into the hood of a car, truck, or other vehicle. The hood is configured to bend near their center point in the event of a front-end impact to dissipate energy and to prevent its disconnection at the hinges, which might possibly drive the hood toward the occupants. 
     In such a front impact  1910  of a vehicle  1912 , the vehicle hood  1914  is configured to deform as normally designed, forming a crease  1916  along a pre-set failure line. In the present embodiment, the housing  102  comprises a hood liner  1918  containing the control material  104 , such as a fire extinguishing chemical, for example a dry chemical powder, and formed to the general shape of the underside of the hood  1914 . The liner  1918  may have surface coverings to feature sound dampening, or have special sound dampening material added between the liner  1918  and the hood  1914 . 
     When the hood  1914  deforms in a collision, the liner  1918  also deforms until it fractures. The liner  1918  may also include scored lines formed on the surface of the liner  1918  to assist in the breakup of the liner  1918 . The control material  104  within the liner  1918  is discharged down onto the engine compartment to prevent any fires or other relevant hazard that might result from the discharge of flammable or otherwise hazardous materials. 
     In another alternative embodiment, the hazard control system  100  is configured to respond to a thermal trigger event. The trigger event may comprise any appropriate thermal trigger event, such as a sudden rise in temperature or a temperature above a selected threshold. For example, referring to  FIG. 20 , the thermal event may be generated by a fire  2010  underneath a fluid reservoir, such as a fuel tank  2012 . The fuel tank  2012  has a housing  102  adjacent or integrated into the tank containing a control material  104 . The housing  102  may be configured in any suitable manner, such as a series of flat panels containing control material  104  placed on the outer surfaces of the fuel tank  2012 , a preformed and molded shape that conforms to the outer shape of the fuel tank  2012 , or actually molded into the outer surface of the tank  2012  itself. In an exemplary embodiment, when a pool fire occurs underneath the fuel tank  2012 , the housing  102  cracks and breaks up, for example due to the resultant thermal loading, and discharges its contents of control material  104 , for example to extinguish or mitigate the pool fire or otherwise control a hazard. 
     The housing  102  is configured to crack and fracture upon exposure to thermal stresses above a selected threshold, such as from a pool fire a few inches from it. For example, the housing  102  suitably includes a bottom face sheet facing the ground constrained by a rigid frame  108  on its perimeter. The face sheet  106  suitably has a higher thermal rate of expansion than the frame  108 , such that when the housing  102  is exposed to heat above a selected threshold, the frame  108  restrains the thermal expansion of the bottom face sheet, thus causing stress within the panel to cause its cracking and rupture. Stress can be applied via pre-loading the panels in the frame  108  or by other heat treatments such that minimal additional thermal stresses are required to achieve the fracture condition. Alternatively, the face sheet  106  may melt, peel back, or otherwise move aside upon exposure to heat above a selected threshold. Further, the control material  104  may be configured to swell upon exposure to heat above the selected threshold to cause or supplement the cracking and rupture of the face sheet  106 . 
     If the housing  102  is integrated into a pre-formed fuel tank, for example in conjunction with an outer shell filled with the control material  104 , the face sheet  106  to rupture may be pre-loaded by controlling of the forming and post-heating processes. Such techniques may be applied to plastic tanks that are molded and are in abundant use today, but which may be particularly vulnerable to failure when exposed to pool fires established underneath them. 
     The hazard control system  100  may also be adapted for use in conjunction with nonflammable hazards, such as an enclosure that houses batteries that may be used on an electric vehicle. If such a container is ruptured, such as due to a collision, and the enclosure is ruptured as well as the batteries, caustic and corrosive battery acids can be released to the environment. Such acids pose a hazard to the vehicle occupants, the environment, rescue personnel, and those hired to inspect the wreckage and transport it to a safe area. 
     A hazard control system  100  according to various aspects of the present invention may be configured for any application where a caustic, corrosive, toxic, or otherwise harmful chemical may be unintentionally released, such as due to a vehicle collision or accident, including tractor-trailers and other transport vehicles that haul such caustic and dangerous chemicals in large quantities. Alternatively, the hazard control system  100  may employ a housing  102  covering or adjacent to the single battery used on virtually all vehicles to inhibit excessive damage resulting from a potential leakage or spray of battery acid within the engine compartment, or toward operators if the battery is damaged in a collision or explodes due to other damage to the battery. 
     Referring to  FIG. 21 , in yet another alternative embodiment, the housing  102  comprises one or more protective panels  2110  adjacent a battery enclosure  2112 , such as on the exterior and/or in the interior of the battery enclosure  2112 . If the enclosure  2112  is damaged, such as in a collision, the battery enclosure  2112  may rupture  2114  and permit the spillage of acid  2120  from the damaged batteries  2116 . The protective panels  2110  are also configured to rupture in the event of damage to the enclosure  2112 , which facilitates discharge of the control material  104 , such as a neutralizing chemical  2118 , to control or mitigate the hazard presented by the released acid. The neutralizing chemical  2118  may be any appropriate material, such as sodium bicarbonate. 
     The various components of the hazard control system  100  may be formed according to any appropriate technique or method. For example, the housing  102  and the core  112  may be cut, cast, extruded, machined, stamped, molded, or otherwise formed to configure to the desired shapes. For example, the housing  102  is suitably vacuum molded, injection molded, or blow molded to form a desired configuration, such as to conform the housing  102  to a particular shape like the exterior of a particular vehicle fuel tank. In particular, the face sheets  106  may be molded so that one exterior surface conforms to the external surface of the fuel tank and the second exterior surface fits within the fuel tank compartment. To form two separate face sheets  106  to be joined with an adhesive, the face sheets  106  are suitably vacuum molded. To form a single integrated housing  102 , the housing  102  is suitably blow molded. 
     In addition, a core  112  may be formed, for example by extrusion. Alternatively, the compartments, channels  610 , or other interior structure of the housing  102  may be generated by forming the interior surface of one or more face sheets  106 , for example during the molding of the face sheets  106 . The face sheets  106  may then be joined to form the housing  102 , suitably surrounding the core  112 , if desired. If the ends are sealed using end caps, the end caps may be attached, for example after insertion of the control material  104 . 
     The housing  102  is suitably formed of a plastic or other material that may exhibit a grain, or a tendency to more easily crack or shatter in a particular direction. To enhance shattering of the housing  102 , the interior structure of the housing  102 , such as the core  112 , the channel partitions  1010 , rows of compartments, or the like, may be configured to extend perpendicularly to the grain. Because the interior structure may tend to support the integrity of the housing  102 , extending the interior structure perpendicular to the grain of the housing  102  material may facilitate easier and/or more extensive shattering of the housing  102 . Orienting the grain perpendicular to the channels  610  promotes opening of multiple channels or compartments to discharge more control material  104 , as the cracks tend to propagate along the grain across multiple channels or compartments. 
     The control material  104  may be added in any suitable manner, such as before joining the housing  102  components or after assembly of the housing  102 . For example, the control material  104  may be added by standing the housing  102  upright and resting on one end and pouring the control material  104  into the upper end of the housing  102 . Alternatively, the control material  104  may be added to the individual compartments or channels  610  in any other appropriate manner, such as by inserting the control material  104  directly into each channel or compartment, for example if the compartments or channels  610  are not interconnected. The control material  104  can be poured, injected under pressure, or otherwise inserted into the channels  610 . 
     The access openings for adding the control material  104  are then suitably closed. If the housing  102  uses end caps, the end cap  810  can be snapped into position, substantially sealing the housing  102 . Any other relevant system for maintaining the control material  104  within the housing  102  may be implemented, such as sealing the openings with caulk, putty, plugs, membranes, tape, or other mechanism. The hazard control system  100  may then be attached to the relevant hazard source. 
     The particular implementations shown and described are illustrative of the invention and its best mode and are not intended to otherwise limit the scope of the present invention in any way. Indeed, for the sake of brevity, conventional manufacturing, connection, preparation, and other functional aspects of the system may not be described in detail. Furthermore, the connecting lines shown in the various figures are intended to represent exemplary functional relationships and/or physical couplings between the various elements. Many alternative or additional functional relationships or physical connections may be present in a practical system. 
     The present invention has been described above with reference to a preferred embodiment. However, changes and modifications may be made to the preferred embodiment without departing from the scope of the present invention. These and other changes or modifications are intended to be included within the scope of the present invention.