Patent Publication Number: US-2006000165-A1

Title: Fire barrier devices

Description:
CROSS REFERENCE TO RELATED APPLICATION  
      This application is a continuation-in-part of application Ser. No. 10/344,563 filed Feb. 21, 2003. 
    
    
     TECHNICAL FIELD  
      This invention relates to barriers and in particular to barrier devices for closing pipes, ducts or conduit which penetrate walls, floors or ceilings of a building in the event of fire.  
     BACKGROUND ART  
      Walls, floors and ceilings of a building usually a multi-story building commonly have pipes, ducts and conduits formed of a plastics material which penetrate the wall, floor or ceiling for carrying services for example water, sewerage or electrical services. In the event of fire however, the penetrating pipes, ducts or conduits allow flames and/or smoke and gases to spread rapidly through the wall, floor or ceiling. To overcome this problem, a number of devices are currently known for use in conjunction with plastic services pipe or ducts for closing off the pipes or ducts in the event of fire. Some of the devices which are used incorporate a heat reactive expandable material or intumescent which is in the form of a flexible wrap and which is located on the inside of a steel or plastic sleeve or housing which is placed about the pipe or duct. When exposed to heat, the heat expandable material will rapidly expand inwardly to squeeze and collapse the pipe which has softened to due heat exposure. These devices can either be surface mounted or fully or semi-cast into masonry floors, walls or ceilings or can be mounted on one or both sides of the floor, wall or ceiling depending upon the direction of risk.  
      The devices which are available however have some deficiencies. Sometimes, the pipe is not fully sealed by the heat expandable material and thus they are not fully effective as fire barriers. Retention devices are essential to retain the intumescent material in their housing however, often the retention devices are not effective with that result that the intumescent material as it expands can fall out of the housing or sleeve and slab. The intumescent material in plastic housings is usually retained in the housing by means of a metal retaining ring. When the intumescent material expands under the influence of heat, it tends to push the ring out of the housing and thus the intumescent material also falls out. Further, some of the devices are made up of a number of components which can be of more than one part, the intumescent material, and a spacer or retention device within the housing. As a result, such devices can be relative complex or time consuming to assemble and are thus costly. A further disadvantage associated with fire barrier devices having metal housings is that the metal rapidly conducts heat through a slab and thus some of the devices of this type do not satisfy fire-rating requirement. To reduce this effect, the housings have to be as low as possible in the slab to reduce the conduction of heat however this sometimes is not possible in the case of larger penetration pipes where the metal housings are relatively large.  
     SUMMARY OF THE INVENTION  
      The present invention aims to provide an improved fire barrier device for providing a barrier to the passage of smoke or gases and/or flames along pipes, ducts or conduits passing through walls, floor or ceilings of a building which is of a simple construction, which is effective in use and which is relatively inexpensive. The present invention in a further aspect aims to provide a method of manufacturing a fire barrier device of the above type. The present invention further aims to provide a method of installing a fire barrier device of the above type in a slab or ceiling.  
      The present invention thus provides in a first aspect a fire barrier device for use with a pipe passing though a wall, floor or ceiling of a building, said pipe having an outer diameter and said device comprising a substantially annular main body, said body comprising a wholly rigid self-supporting body and being moulded from a mouldable material containing a heat reactive expandable material, said body having a central axis and a bore moulded with said body and extending along said central axis, at least a portion of said bore having a diameter substantially the same as the outer diameter of said pipe.  
      The term “pipe” or “services pipe” as used throughout the specification and claims includes any pipe, duct or conduit which carries services in a building such as a water pipe, a stormwater pipe, or a drain pipe.  
      Preferably, fire barrier device is moulded in an injection moulding process and the material for forming the fire barrier device and for injection moulding includes the heat reactive expandable (or intumescent) material and a carrier or plasticiser. Typically, the intumescent material comprises graphite in particulate form. The carrier or plasticiser may comprise HDPE (high density polyethylene) or other similar material. The material may additionally include a fire retardant to prevent or minimize flaming or burning of the material. A typical flame or fire retardant may comprise sodium silicate. The material may additionally include a smoke suppressant to prevent excess generation of smoke when the fire barrier device is subject to heat or flames.  
      The fire barrier device may be mounted to a wall, floor or ceiling of a building around a pipe, duct or conduit penetrating the wall, floor or ceiling or installed within a wall, floor or ceiling such as a slab wall, floor or ceiling either by being cast in situ within a slab or located in a recess in the slab around the pipe, duct or conduit.  
      In another aspect, the present invention provides a fire barrier device for use with a services pipe, said fire barrier device being moulded from a material containing a heat reactive expandable material and being wholly rigid and self-supporting, said fire barrier device having:  
      a central axis and first and second ends spaced apart along said central axis,  
      an axial passage extending along said central axis from said first end to said second end for receipt of said pipe,  
      a radially extending main heat expandable body centered on said central axis, said main body having a maximum outer diameter,  
      mounting means at said second end for mounting said fire barrier device, said mounting means comprising one of an annular flange or a plurality of lugs, and  
      wherein said fire barrier device has a reduced diameter region between said main body and said mounting means, the outer diameter of said reduced diameter region being less than the maximum outer diameter of said main body.  
      The fire barrier device is typically encased within a slab of settable material such as concrete. The slab typically is constructed on formwork which defines one side of the slab. The pipe has an external diameter and the axial passage having a portion of internal diameter substantially the same as the external diameter of said pipe. The mounting means is adapted to secure the fire barrier device to the formwork during construction of the slab.  
      Preferably, the main body is of substantially annular form to extend in use generally radially of the pipe so as to be retained within the slab by the material thereof when installed within the slab during the construction thereof. Typically at least portion of the outer surface of the main body is curved. The main body may be of substantially spherical or part spherical configuration with the maximum diameter region thereof being arranged in use within the slab and the minimum diameter region being located in use adjacent the one side of the slab. The spherical or part-spherical external surface or surfaces which is centered on the axial passage cooperate/s with the slab material to concentrate the expansion forces of the heat expandable material to more effective close off the pipe.  
      Alternatively, the main body may be of frustonconical form centered on the axis of the passage. The external surface of the body however may be of any other divergent form in cross section. For example, the body may have a stepped outer wall defining a shoulder which cooperates with the material of the slab to retain the device within the slab.  
      The main body may additionally or alternatively include integrally formed retaining means adapted for cooperation and bonding with the material of the slab. The retaining means may comprise an external groove in the body in which the “wet” material of the slab locates during slab construction. The groove suitably is a substantially annular groove extending peripherally about the main body. The main body may include one or more peripherally extending grooves. Alternatively, or additionally, the main body may include one or more radially extending projections which are adapted to cooperate with the slab material to assist in retaining the main body within the slab. The projections may be of substantially annular form to extend substantially peripherally of the body.  
      The mounting means is suitably integrally formed with the main body and the Annular flange or lugs may comprise a radially extending annular flange or radially extending lugs by which the device may be secured to the formwork. The flange or lugs may include openings or slots to receive or locate fasteners such as nails, cleats or screws to secure the device to the formwork or alternatively, nails, or cleats may be driven through the flange or lugs into the formwork. In another form, means may be provided for cooperation with the flange for holding or clamping the flange to the formwork. Such means may be in the form of an annular clamping ring which is engageable with the flange. Any suitably fasteners may be used for fastening the clamping ring to the formwork. Typically the fasteners may be cleats or other nails or screws.  
      The axial passage through the main body may include a first portion at one end of the main body and a second portion larger than the first portion at or adjacent the opposite end of the main body. Suitably, the first portion is remote from the mounting means and has an internal diameter substantially the same as the outer diameter of the pipe so as to grip and support the latter during installation thereof in the wall or floor slab.  
      The second enlarged portion of the axial passage may extend from the first portion, being stepped outwardly therefrom. The second enlarged portion may extend to adjacent the mounting means to open in use to the one side of the wall or slab after formation thereof.  
      The mounting means may include between the main body and annular flange or lugs, a wall which is coaxial with the main body and formed integrally therewith with the main body extending radially outwardly of the wall. A sleeve-like member or wall may join the annular flange or lugs or may include an outwardly stepped or inclined portion to join the annular flange or lugs. The wall defines at least adjacent the flange a third passage portion which extends from and is coaxial with the second portion of the passage through the main body. Both the second and third passage portions are suitably of greater diameter than the pipe with which the device is to be used so as to define an annular space between the main body and sleeve like member which opens to one side of the slab in the direction of the fire risk such that heat from a fire can rapidly reach the main body to cause rapid expansion thereof. The annular space in addition, allows connection of the pipe with a further pipe, duct or conduit or fitting.  
      Preferably, the main body joins at its end opposite the mounting means, a collar which is coaxial with the axial bore. The collar may be formed integrally with the main body. The collar has an internal diameter substantially the same as the pipe with which the device is to be used so as to firmly engage and support the pipe, duct or conduit during installation in a slab. In addition, the collar provides a seal with the pipe to prevent escape of smoke and/or gases in the event of a fire. This ensures that smoke is contained in the pipe and is directed out of the building through the pipe rather than being trapped in the building. The collar may define at least a part of the first portion of the axial passage extending through the main body.  
      In another form, mounting means which may be separate from the main body may be provided for mounting the main body to the slab formwork. Suitably the mounting means is of generally annular form and defines an annular flange by which the device may be secured to the formwork. The flange may include spaced openings to receive fasteners such as nails, cleats or screws to secure the device to the formwork or alternatively nails or cleats may be driven through the flange into the formwork. The mounting means may be in the form of an annular spacer which includes an annular side wall extending axially from the annular flange. The annular spacer may also include a further radially inwardly directed wall upon which the moulded main body is seated and is secured. The moulded main body may be secured to the spacer by adhesives or alternatively by a mechanical connecting arrangement. For example, the main body may be formed with members such as lugs which cooperate with slots or apertures in the inwardly directed wall of the spacer such that relative rotation between the spacer and main body will secure them together. Alternatively, the spacer may include members which project into the material of the main body.  
      Retaining means may also be provided on the spacer to assist in retaining the device in the slab. The means on the spacer may comprise an annular bead or enlargement or alternatively an annular groove in the spacer. The bead, enlargement or groove may be formed in the annular side wall of the spacer.  
      In yet an alternative arrangement, the mounting means may comprise a hollow body formed of a heat softenable material and the main body of intumescent material which is mounted to surround the hollow body. The hollow body may have a side wall surrounding an opening through which a duct or pipe may pass, and the main body is in the form of a collar of a heat reactive expandable material surrounding the side wall and extending outwardly therefrom so as to retain said device in the slab when said material thereof sets or cures.  
      The collar of heat expandable or intumescent material may be formed integrally with the hollow body which itself is thus formed of the heat expandable material or alternatively, the annular collar is separate of the hollow body and may be located thereover coaxially. The annular collar may supported or seat on a shoulder formed in an external wall of the hollow body. The annular collar may be of any cross sectional form but typically may have a curved outer configuration. The annular collar suitably extends radially outwardly of the body so as to be retained in the material of the slab.  
      The wall of the hollow body may have means at one end for securing the body to formwork defining a boundary of said slab during the formation thereof. The means at one end may comprise and annular flange.  
      The hollow body may be in the configuration of a sleeve. Suitably, the outer wall of the sleeve is stepped to define a shoulder upon which the collar may seat. The portion of the sleeve wall adjacent the shoulder and within the collar is preferably relatively thin so as to soften rapidly when subject to heat and not prevent expansion of the collar. Preferably also the outer diameter of the sleeve wall portion is substantially the same as the internal diameter of the collar such that the later may be firmly engaged with the sleeve wall portion. The upper portion of the sleeve suitably has an internal diameter such as to enable the sleeve to firmly grip the outer wall of the duct or pipe to support the duct or pipe in an upstanding attitude.  
      In a further embodiment, a sleeve may be associated with the device to act as a stack through the slab for accepting the pipe, duct or conduit therethrough, the sleeve being of such a length as to project beyond the slab when formed. The sleeve may be secured to any part of the device such as to the collar of the device where provided for example by adhesives or mechanical fasteners. In a further embodiment, the sleeve may be formed integrally with the device and extend coaxially therefrom relative to the axial bore through the body.  
      The device may also include on its underside, a radially extending recess for accommodating radially extending lugs of a joining sleeve or fitting. The recess may be defined by an integrally formed radially extending tunnel shaped member extending from the main body. The joining sleeve or fitting may be of the type which incorporates a heating coil to effect joining by heat fusion to a pipe, duct or conduit which terminates in connecting terminal or lugs extending radially therefrom for connection to a current source.  
      The present invention in yet a further aspect provides a method of installing a fire barrier device of the above type in a wall, floor or ceiling slab formed of a settable material, said method including the steps of inserting a pipe into the passage of said main body, securing said device to formwork defining one side of said wall, floor or ceiling slab, and applying the settable material of said slab to said formwork and around said fire barrier device such that said settable material encases said device and leaves said pipe projecting beyond said slab. The method may also include the step of removing the formwork when said settable material is set or cured, said device being retained in said slab by cooperation between the material of said slab and said device.  
      Typically the formwork is formed of timber and is removed after formation of the slab. In however an alternative arrangement, the formwork may be metal decking sheets such as that known as Bondeck and remain in situ after curing of the slab material. The fire barrier devices in such situations are secured to the metal sheets by metal fasteners such as screws or rivets and a circular opening is formed in the metal decking in alignment with the fire barrier device to enable the service line or pipe to be passed therethrough. The opening may be formed before or after affixing of the fire barrier device. To support the service lines or pipes during casting of the slab, radially extending stop means may be associated with the fire barrier device to span the device adjacent the mounting flange, the stop means being abutted by the end of the pipe.  
      In another aspect, the present invention provides a fire barrier device for use with a services pipe, said fire barrier device comprising a body moulded from a material containing a heat reactive expandable material, said body being a self-supporting and wholly rigid body, said body having: a central axis and first and second ends spaced apart along said central axis, an axial bore extending along said central axis from said first end to said second end for receipt of said pipe, a radially extending main heat expandable portion between said first end and said second end and centered on said central axis, said main heat expandable portion having a maximum transverse dimension in a direction normal to said central axis, mounting means at said second end for mounting said fire barrier device, and wherein said fire barrier device has, between said main heat expandable portion and said mounting means, a region of a transverse dimension less than the maximum transverse dimension of said main heat expandable portion.  
      In yet a further aspect, the present invention provides a fire barrier device in combination with a pipe passing through a slab of a settable material, said pipe having an external diameter and said barrier device being encased within said slab and comprising: a main body moulded from a mouldable material containing a heat reactive expandable material, said main body having first and second opposite ends and an axial bore extending therethrough and receiving said pipe, said main body being a wholly rigid body; and a collar at said first end of, and joining said, main body, said collar being coaxial with said axial bore and having an internal diameter substantially the same as the external diameter of said pipe so as to engage and support said pipe.  
      In another aspect, the present invention provides a fire barrier device in combination with a pipe located within a slab of a settable material, said pipe having an external diameter and said barrier device being encased within said slab and having: a central axis and first and second ends spaced apart along said central axis, a passage extending along said central axis and receiving said pipe, said passage having a portion of an internal diameter substantially the same as the external diameter of said pipe, a main body heat expandable body moulded from a mouldable material containing a heat reactive expandable material, said main body being centered on said central axis and extending radially outwardly relative to said central axis, said body having a maximum outer diameter and being wholly rigid, mounting means at said second end for mounting said fire barrier device, said mounting means comprising one of an annular flange or a plurality of lugs, and wherein said fire barrier device has a region between said main body and said mounting means of an outer diameter less than the maximum outer diameter of said main body.  
     BRIEF DESCRIPTION OF THE DRAWINGS  
      In order that the invention may be more readily understood and put into practical effect, reference will now be made to the accompanying drawings which illustrate a preferred embodiment of the invention and wherein:  
       FIG. 1  illustrates the fire barrier device according to an embodiment of the invention in side view;  
       FIG. 2  illustrates in perspective view, the fire barrier device of  FIG. 1 ;  
       FIG. 3  illustrates in sectional view, the manner in which the fire barrier device or  FIGS. 1 and 2  is installed within a slab;  
       FIG. 4  illustrates in sectional view, the installed fire barrier device within a slab;  
       FIGS. 5 and 6  illustrate in side and perspective views a further form of fire barrier device according to the invention similar to the embodiment of  FIGS. 1 and 2 ;  
       FIG. 7  is a perspective view of a further form of fire barrier device according to the present invention;  
       FIG. 8  is a side elevational view of the device of  FIG. 7 ;  
       FIG. 9  is a cross sectional view of the device of  FIG. 7  installed within a slab.  
       FIG. 10  illustrates in plan view, a fire barrier device according to a further embodiment of the invention;  
       FIG. 11  is a sectional view of the fire barrier device of along line A-A of  FIG. 10  with associated clamping ring;  
       FIG. 12  illustrates the manner in which the fire barrier device of  FIG. 10  is installed within a slab;  
       FIG. 13  illustrates in sectional view, the installed fire barrier device of  FIG. 10  within the slab;  
       FIG. 14  is a plan view of a fire barrier device according to a further embodiment of the invention;  
       FIG. 15  is a sectional view along line B-B of  FIG. 14 ;  
       FIG. 16  illustrates in sectional view, the manner in which the device of  FIGS. 14 and 15  is installed within a slab;  
       FIG. 17  illustrates in sectional view the fire barrier device of  FIGS. 14 and 15  installed in a ceiling;  
       FIG. 18  illustrates in sectional view a further form of fire barrier device according to the invention;  
       FIG. 19  illustrates in perspective view, a fire barrier device according to a further embodiment of the invention;  
       FIG. 20  illustrates the fire barrier device of  FIG. 19  in side view;  
       FIG. 21  illustrates in sectional view the manner in which the fire barrier device of  FIGS. 19 and 20  is installed within a slab;  
       FIG. 22  illustrates in sectional view, the installed fire barrier device of  FIGS. 19 and 20  within the slab;  
       FIG. 23  illustrates in perspective view, a fire barrier device according to a further embodiment of the invention;  
       FIG. 24  illustrates the fire barrier device of  FIG. 23  in side view;  
       FIG. 25  illustrates in sectional view the manner in which the fire barrier device of  FIGS. 23 and 24  is installed within a slab; and  
       FIG. 26  illustrates in sectional view, the installed fire barrier device within the slab.  
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
      Referring to the drawings and firstly to  FIGS. 1 and 2 , there is illustrated a fire barrier device  10  according to a first embodiment of the present invention including a main body  11  integrally formed with a mounting portion  12  which is adapted to mount the body  11  in a desired position within a slab of settable material such as concrete as described further below. The device  10  comprising the main body  11  and mounting portion  12  are formed integrally in a conventional injection moulding process so that the device  10  is a wholly rigid device. The material for moulding includes a heat reactive expandable material or intumescent material which has suitable properties such as to expand when subject to heat as encountered in a fire. Typically the intumescent material comprises graphite. The moulding material also includes a plasticiser or carrier for example HDPE to enable moulding, a smoke suppressant and a fire suppressant for example sodium silicate. The main body  11  is circular in cross-section and has an external part spherical wall  13  centred on the central axis of the body  11  in which is formed an annular groove  14 . Wall  13  has a maximum diameter adjacent the mounting portion  12  and the body  11  is stepped inwardly adjacent portion  12  to present an annular wall portion or shoulder  13 ′ which faces the mounting portion  12 . The device  10  comprises a self-supporting device which needs no external support and further is wholly rigid.  
      The main body  11  joins at its upper end an integrally formed collar  15  which defines a passage or bore  16  with an internal diameter substantially the same as the external diameter of pipe, duct or conduit to be received in the device  10 . The bore  16  is stepped outwardly in the main body  11  to form a second enlarged bore  17  which extends through the main body  11 .  
      The mounting section  12  includes a sleeve-like member or wall  18  extending from and formed integrally with the main body  11 , the bore  17  extending through the member  18 . The member  18  is stepped outwardly through an annular radially extending wall  19  and a second cylindrical wall  20 , the latter terminating in a radially extending flange  21 . The annular flange  21  includes circumferentially spaced slots  22  for locating fasteners. Alternatively, the slots  22  may be replaced by preformed apertures in the flange  21 .  
      The device  10  may be used in a number of different situations to close off pipes, ducts or conduits passing through walls, floor or ceilings. Most commonly, however the device  10  may be installed within a concrete or concrete composite slab wall, floor or ceiling during its construction in the manner shown in  FIGS. 3 and 4 . A pipe  23  is initially passed through the collar  15  such that it is frictionally gripped by the internal wall thereof and thereafter the device  10  may be secured to formwork  24  which defines one face of a concrete slab to be formed. This is achieved by means of the flange  21  of the device  10  which is seated on the formwork  24  with cleats  25  or other fasteners located by the slots  22  drive into the formwork  24  to clamp the flange  21  and thus the device  10  to the formwork  24 . Of course, devices  10  may be initially secured to the formwork  24  at the desired positions where the service pipes  23  are to penetrate the slab and thereafter the pipes  23  inserted into the devices  10  to be supported in an upstanding attitude in the manner shown, the lengths of the pipes  23  being such that they will extend beyond the side of the wall, floor or ceiling slab to be formed opposite the formwork  24 .  
      The concrete or concrete composite material  26  may then be poured or deposited onto the formwork  24  and around the devices  10  secured to the formwork  24  and pipe  23  until the required thickness of the wall, floor or ceiling slab  27  is achieved. As shown, the pipe  23  extends above or beyond the slab  27  to enable connection to further pipes to form the service line through the slab  27 . After the concrete or concrete composite material has cured or set, the formwork  24  is removed as shown in  FIG. 4  which leaves the device  10  embedded in the concrete slab  27 . The device is retained in the slab  27  due to the radially enlarged form of the main body  11  of the device which is embedded within the slab  27 . Retention is further enhanced by the interlocking achieved through the material  26  of the slab filling the annular groove  14  and further because of the slab material filling the undercut annular space  28  between the shoulder  13 ′ and the annular wall  19 . The device  10  is thus anchored within the formed slab wall, floor or ceiling.  
      The bore  17  in the main body  11  defines with the pipe  23 , an annular space  29  which opens through the mounting section  12  to the underside of the slab and which ensures that in the event of fire on the underside of the slab  27 , the generated heat will be directed towards the inside of the main body  11  so that the intumescent material thereof is rapidly subject to heat which will cause it to expand and close over the softened pipe  23  as illustrated in dotted outline in  FIG. 4 . The curved nature of the external wall of the body  11  ensures that there is a concentrated expansion of the intumescent material as indicated by the arrows in  FIG. 4  reacting against the surrounding slab material  26  which directs the expansion forces generally radially as illustrated to rapidly close over the softened pipe  23  as indicated in dotted outline. The space  29  also facilitates the connection between the pipe  23  and a further pipe or other fitting such as an elbow  30  (shown in dotted outline) having a mating female socket for joining to the end of the pipe  23  within the space  29  by suitable adhesives usually contact adhesives.  
      The annular finger of concrete or other settable material in the space  28  defined by the outwardly extending wall  19  serves to govern the exposure of part of the body  11  to heat to control the rate of expansion of the body  11  and so that the device  10  has sufficient fire rating and will continue to be effective over a considerable period of time.  
      Whilst the body  11  is preferably of part-spherical external configuration as illustrated, it may be of alternate configurations for example of toroidal shape or simple ring-like shape and include alternative retention means for retaining the device  10  in the slab  27 . For example, the body portion  11  may have outward projections which may be of annular form to cooperate with the slab material  26 . The cylindrical wall or member  18  in some embodiments may simply extend downwardly to join the annular flange  21  and thus in this case, the walls  19  and  20  may be eliminated. In yet an alternative configuration, the annular flange  21  and wall  20  may be eliminated and the wall  19  radially extended to service as a mounting flange for the device.  
      In yet a simplified form, the mounting portion  12  of the device may be eliminated such that the main body  11  may seat on the formwork so that the bore  17  opens to the underside of the slab  27 . In another form, the mounting section  12  may be eliminated and the body  11  be of simple annular form with the bore  17  reduced to the internal diameter of the collar  16  to engage firmly a pipe, duct or conduit with which the device is to be used. The main body  11  may the be located within the slab  27  at any desired position prior to forming the slab  27  such that it is retained within the slab  27  about a pipe passing through the slab  27 . Alternatively, the device  10  may be engaged about a pipe externally of a slab.  
       FIGS. 5 and 6  illustrate an alternative form of fire barrier device  31  according to the invention which is similar to the embodiment of  FIGS. 1 and 2  and which is used in the same manner as that described with reference to  FIGS. 3 and 4 . In  FIGS. 5 and 6 , like parts to those of  FIGS. 1 and 2  have been given like numerals. In this case the collar  15  is of extended length to provide additional support to a pipe or duct  23  passing therethrough, the collar  12  also extending into the main body  11 . Further the wall  20  in this case is inclined outwardly.  
      The devices  10  and  31  may also be used with a sleeve-like member  32  (shown in  FIG. 3  in dotted outline) which forms a stack extending beyond the top side of the slab  27  with the pipe  23  passing coaxially therethrough. The sleeve-like member  32  may be fixed to the collar  12  by mechanical or adhesive means or alternative may be formed integrally with the device  10  or  31 .  
      Referring now to FIGS.  7  to  9 , there is illustrated a further embodiment of fire barrier device  33  according to the present invention in which like components to those of the embodiment of FIGS.  1  to  6  have been given like numerals. The device  33  as in the first embodiment includes a collar  15  for closely receiving a pipe, duct or conduit, a substantially annular main body  11  and a mounting portion  12  comprising an annular wall or member  18  which is outwardly angled to join an annular mounting flange  21 . In this embodiment, a radially extending tunnel shaped member  34  is formed integrally with the device  33  and intercepts the wall  18  to define on the underside of the device  32 , a radially extending recess  35  extending from the space  29  for a purpose which will hereinafter become apparent. The tunnel shaped member  34  is closed at its outer end  36 .  
      The device  33  may be installed and used in the same manner as the collar  10  as described with reference to  FIGS. 3 and 4 . The device  33  however is particularly suited for use with HDPE or similar pipes which are joined by heatable joining sleeves  37  (see  FIG. 9 ). Sleeves  37  of this type are used for joining by heat fusion, pipes formed of HDPE or other heat formable or joinable material which cannot be glued with conventional adhesives. The joining sleeves  37  are provided with heating elements which extend circumferentially of the sleeve and which terminate in a pair of radially extending terminals  38  to which a current can be applied through wires  39  connected to the terminals  38  via suitable plugs to effect heating of the sleeve  37 . A first HDPE pipe  40  is inserted into the device  33  to be gripped by the collar  15  and supported in an upstanding attitude prior to pouring the settable material on to the formwork  24  (shown in dotted outline) to form the slab  27 . The sleeve  37  may then be engaged with the lower end of the pipe  40  in the space  29  with the radially extending recess  35  accommodating the radially extending terminal or terminals  38  of the sleeve  37  providing sufficient room for receipt of the connecting plugs of the wires  39 . A further HDPE pipe  41  (or other fitting) may be inserted into the lower end of the sleeve  37  and current applied through the wires  39  to effect connection and sealing by fusion heating between the sleeve  37  and pipes  40  and  41  to form the service line through the slab  27 . After connection, the wires  39  of course are disconnected from the terminals  38 .  
      Whilst the devices  10 ,  31  and  33  are preferably installed within a slab, they may be secured to one or both sides of a slab and around a service line or pipe extending through the slab or in a ceiling space. In the latter installation for example, the devices  10  (or  31  or  33 ) may be secured to a plasterboard ceiling panel with an enlarged opening formed in the panel in alignment with the device  10  (or  31  or  33 ) such that a pipe  23  supported by the device  10  (or  31  or  33 ) may be secured to a further pipe or fitting through a female socket on the end of the further pipe or fitting which locates within the enlarged opening and space  29  in the device  10  (or  31  or  33 ). The device  10  (or  31  or  33 ) will function in the same manner as that described above to shut over the service pipe in the event of fire.  
      Referring now to  FIGS. 10 and 11 , there is illustrated a fire barrier device  42  according to a further embodiment of the present invention, the device  42  comprising or consisting of a heat reactive intumescent material and being moulded as a wholly rigid self supporting device in one piece in any suitable moulding apparatus such as by injection moulding. The device  42  is of a generally hat shaped configuration in side view and includes a main body  43  which is circular in cross-section and which has a generally spherical outer configuration defined by an external curved wall  44  such that the diameter of the body  43  in the middle thereof is greater than the diameter at each end for a purpose which will become apparent. A central bore  45  extends through the body  43  and is of a stepped configuration to define at one end a first bore portion  46  which is of a diameter substantially the same as the diameter of a pipe or duct to be passed through the body  43  and a second bore portion  47  at the other end of the body  43  which is of an enlarged diameter relative to the bore portion  46 . Extending peripherally about the end of the body  43  adjacent the bore portion  47  is a peripheral flange or rim  48  which extends generally radially of the body  43 . The outer edge of the flange or rim  48  is provided with an annular recess  49  formed in the surface of the flange or rim  48  adjacent the body  43 . Adapted for cooperation with the flange or rim  48  is an annular stepped securing ring  50  which includes an inwardly projecting rim portion  51  complementary to and adapted to be received in the recess  49 . The securing ring  50  may be formed of plastics or metal and may be provide with a series of preformed apertures  52  for accepting cleats or other or other fasteners  53 . Alternatively, the material of the ring  50  may be such that it may be easily penetrated by cleats  53  or other fasteners driven therethrough.  
      As above, the device  42  may be used in a number of different situations to close off pipes or ducts passing through walls, floors, or ceilings. Most commonly however, the device  42  is installed within a concrete or concrete composite slab wall, floor or ceiling during its construction in the manner shown in  FIGS. 12 and 13 . A pipe or duct  54  is initially passed through the bore  45  such that it is frictionally gripped by walls of the first portion  46  of the bore  45  and thereafter the device  42  may be secured to formwork  55  which defines one face of a concrete slab to be formed. This is achieved by means of the securing ring  50  which is engaged with the flange  48  in the above described manner and cleats  53  or other fasteners are driven through the ring  50  into the formwork  55  to clamp the flange  48  and thus the device  42  to the formwork  55 . Of course, devices  42  may be initially secured to the formwork  55  at the desired positions where the service pipes or ducts are to penetrate the slab and thereafter the pipes or ducts  54  are inserted into the devices  42  to be upstanding therefrom in the manner shown, the lengths of the pipes or ducts  54  being such that they will extend beyond the side of the wall, floor or ceiling slab to be formed opposite the formwork  55 .  
      The concrete or concrete composite material  56  may then be poured or deposited onto the formwork  55  and around the devices  42  secured to the formwork  55  and pipe or duct  54  until the required thickness of the wall, floor or ceiling is achieved. As shown, the pipe or duct  54  extends above or beyond the slab to enable connection with joining pipes or ducts. After the concrete or concrete composite material has cured or set, the formwork  55  is removed as shown in  FIG. 13  which leaves the device  42  embedded in the concrete slab. The device  42  is retained in the concrete slab due to the interlocking achieved through the material of the slab filling the undercut portion  57  of the device  42  defined between the curved wall  44  of the device  42  and the flange  48  and further because the largest diameter portion of the device  42  is located within the slab at a position spaced from the adjacent side of the slab defined by the formwork  55 . The device  42  is thus locked within the formed slab wall, floor or ceiling.  
      The enlarged diameter portion  47  of the bore  45  defines with the pipe or duct  54 , an annular space  58  which ensures that in the event of fire, the generated heat will be directed towards the enlarged portion of the body  42  so that the intumescent material is rapidly subject to heat which will cause it to expand and close over the softened pipe  55 . The curved nature of the wall  44  of the body  43  ensures that there is a concentrated expansion of the heat expandable material as indicated by the arrows in  FIG. 13  against the wall  44  which directs the forces generally radially as illustrated to rapidly close over the softened pipe  54  as indicated in dotted outline. Further the space  58  facilitates the connection between the pipe or duct  54  and a further pipe or duct  59  (showing in dotted outline) having a mating female socket for joining to the end of the pipe or duct  54  within the space  58 .  
       FIGS. 14 and 15  illustrate a further embodiment of fire barrier device  60  according to the invention in which similar components to the embodiment of  FIGS. 12 and 13  have been given like numerals. In this case however, the body  61  is of a generally half-spherical configuration having a curved external wall  62  which is at a minimum diameter adjacent the securing flange  48  and at a maximum at its opposite end  63 .  
      This device  60  is used in a similar manner to that described above with the flange  48  being secured to formwork  55  as shown in  FIG. 16  and a pipe or duct  54  being received within the body  62 , passing through the bore  45  to be supported in an upstanding attitude by the bore portion  46 . To form the slab, concrete or other settable material  56  is applied to the formwork  55 , the latter normally being removed after curing or setting of the material  56 . The device  60  thus remains in situ within the slab being held therein due to the diverging nature of the side wall  62  which places the maximum diameter end  63  of the body  61  within the slab and the minimum diameter portion  64  adjacent one side of the slab.  
      Again in this embodiment in the event of fire, the heat applied to the intumescent material of the body  60  will cause that material to expand with the expansion forces being concentrated by the curved surface of the concrete at the interface with the side wall  62  of the body  61  in a generally radial direction as indicated by the arrows in  FIG. 16  to rapidly close over the softening pipe  54 .  
      Whilst the devices described with reference to FIGS.  1  to  16  are preferably installed within a slab, they may be secured to one or both sides of a slab and around a service line or pipe extending through the slab or in a ceiling space as illustrated in  FIG. 17 . In the latter installation, the device  60  (or  10 ,  31 ,  33  or  42 ) is secured to plasterboard ceiling panels  65  by the appropriate fastening arrangement as described above with an enlarged opening  66  being formed in the panels  65  in alignment with the bore portions  46  and  47  in the body  61  such that a pipe  54  supported by the body  61  may be secured to a further pipe  68  (shown in dotted outline) through a female socket  69  on the end of the further pipe  68  which locates within the opening  66  and bore portion  47 . The device  60  (or  10 ,  31 ,  33  or  42 ) will function in the same manner as that described above with the heat expandable or intumescent material of the body expanding when subject to heat to close over the pipe  54 .  
      Referring now to  FIG. 18 , there is illustrates a further embodiment of fire barrier device  70  according to the invention and wherein like components to the components of the embodiments of FIGS.  10  to  16  have been given like numerals. In this case, the body  71  of the device  70  comprises an enlarged collar  72  having an internal bore  73  for neatly receiving the pipe  54  and an inner annular leg  74  which extends from the collar  72  at a position radially inwardly from the outer circumference thereof to define a shoulder  75  which cooperates with the concrete or other settable material  56  of the slab to be formed to retain the device  70  in the slab. The leg  74  terminates in an annular flange  76  which may be secured to the formwork  55  by cleats through the flange  76  or by a separate clamping ring  50  as in the embodiments of FIGS.  10  to  17 . The pipe  54  is gripped by the walls of the bore  73  which support the pipe  54  in an upstanding attitude whilst the concrete  56  is applied to the formwork  55 . The leg  74  forms with the pipe  54  a space  77  which allows rapid passage of heat of the fire to the collar  72  of the device  70  to cause rapid expansion thereof as shown in dotted outline to close over the pipe  54 . The space  77  also allows for connection of the pipe  54  with a further pipe in a similar manner to that shown in  FIG. 13  after the formwork  55  has been removed. The device  70  as well as being used within a slab may also be used in a ceiling space as in the arrangement of  FIG. 17 .  
      The devices  42 ,  60  and  70  by being moulded in one piece are wholly rigid and self supporting and do not have an external housing and thus there is no rapid transfer of heat as in the prior art devices where the housing is metal. Further the material of the devices is self-supporting within or out of a slab and no retention device is required to maintain the devices within the slab. When installed within a slab, the material from which the bodies of the devices are formed may form a mechanical and/or chemical bond with the material of the slab to further assist in retention of the bodies within the slab. The devices additionally are highly resistant to weather conditions, moisture or other adverse environments. Whilst the devices  42  or  60  in a preferred form have an outer curved wall which provides an enlarged body of intumescent material for closing a pipe or duct, the curved wall may be of other configurations which flares or is stepped outwardly between the minimum and maximum portions of the device as in  FIG. 9  or which have an enlarged portion located in use within the slab. Further whilst the devices  42 ,  60  and  70  are preferably of circular cross section, they may be of square cross sectional form or of any other cross section. Whilst the device  42  and  60  are shown to be secured to formwork by a clamping ring  50 , they may be secured thereto by cleats or other fasteners driven directly through the flange  48  or preformed apertures or slots therein.  
      Referring now to FIGS.  19  to  21 , there is illustrated a fire barrier device  78  according to a further embodiment of the present invention, the device  78  comprising an annular spacer  79  preferably formed of metal having an annular side wall  80 , an annular flange  81  at one end of the wall  80  and a disc-like end wall  82  (see  FIG. 21 ) at the opposite end of the side wall  80  and extending inwardly towards the central axis of the spacer  79 . Seated upon the end wall  82  is an annular body  83  moulded from a material comprising or consisting of a heat reactive intumescent material as described above, the body  83  being rigid and self supporting. The body  83  is circular in cross-section and has an upper collar  84  and a curved external wall  85  curving inwardly from the outer periphery of the spacer  79  to the collar  84  so as to be externally of part-spherical form. The body portion  85  has an internal bore portion  86  of an internal diameter greater than the internal diameter of the collar  84  and has in its external surface  85  an annular radially inwardly extending groove  87 . The body  83  is attached to the spacer  79  by any suitable means such as by suitable adhesives or by a mechanical connection. The mechanical connection may include lugs on the body  83  which locate in slots or apertures in the disc-like wall  82 . The body portion  85  may be locked to the spacer  79  by rotating one relative to the other. Typically the body  85  may include downwardly extending headed lugs which may locate in keyhole shaped apertures in the wall  82  such that when rotated relative to each other, the body  85  becomes mechanically connected to the spacer  79 . The collar  84  has an internal bore which is of a diameter substantially the same as the diameter of a pipe or duct to be passed through the device  78 .  
      The device  78  may be used in a number of different situations to close off pipes or ducts passing through walls, floors, or ceilings. Most commonly however, the device  78  is installed within a concrete or concrete composite slab wall, floor or ceiling during its construction in the manner shown in  FIGS. 21 and 22 . A pipe or duct  90  is initially passed through the sleeve  84  such that it is frictionally gripped by the internal wall thereof and thereafter the device  78  may be secured to formwork  91  which defines one face of a concrete slab to be formed. This is achieved by means of the flange  81  of the spacer  79  with cleats  92  or other fasteners are driven through the flange  81  into the formwork  91  to clamp the flange  81  and thus the device  78  to the formwork  91 . Of course, devices  78  may be initially secured to the formwork  91  at the desired positions where the service pipes or ducts  90  are to penetrate the slab and thereafter the pipes or ducts  90  are inserted into the devices  78  to be upstanding therefrom in the manner shown, the lengths of the pipes or ducts  90  being such that they will extend beyond the side of the wall, floor or ceiling slab to be formed opposite the formwork  91 .  
      The concrete or concrete composite material  93  may then be poured or deposited onto the formwork  91  and around the devices  78  secured to the formwork  91  and pipe or duct  90  until the required thickness of the wall, floor or ceiling is achieved to form the slab  94 . As shown, the pipe or duct  90  extends above or beyond the slab  94  to enable connection with joining pipes or ducts. After the concrete or concrete composite material  93  has cured or set, the formwork  91  is removed as shown in  FIG. 22  which leaves the device  78  embedded in the concrete slab  94 . The device  78  is retained in the concrete slab due to the interlocking achieved through the material  93  of the slab  94  filling the annular groove  87 . The slab material  93  will also exert a grip on the side wall  80  of the spacer  79 . The device  78  is thus locked within the formed slab wall, floor or ceiling.  
      The bore  86  in the body  83  defines with the pipe or duct  90 , an annular space  95  which ensures that in the event of fire, the generated heat will be directed towards the inside of the body  83  so that the intumescent material thereof is rapidly subject to heat which will cause it to expand and close over the softened pipe  90  as illustrates in dotted outline in  FIG. 22 . The curved nature of the external wall of the body  83  ensures that there is a concentrated expansion of the intumescent material as indicated by the arrows in  FIG. 22  reacting against the surrounding slab material  93  which directs the forces generally radially as illustrates to rapidly close over the softened pipe  90  as indicated in dotted outline. Further the space  95  facilitates the connection between the pipe or duct  90  and a further pipe or duct  96  (shown in dotted outline) having a mating female socket for joining to the end of the pipe or duct  90  within the space  95  by suitable adhesives usually contact adhesives.  
      Whilst the body  83  is preferably of the part-spherical configuration as shown, it may be of alternate configurations and include alternative retention means for retaining the device  78  in the slab. For example, the body  83  may have outwardly extending projections which may be of annular form to cooperate with the slab material  93 . The annular spacer  79  may also include on its external wall  80 , outward projections which may also be in the form of an annular outwardly extending protrusion. In yet a further arrangement, the body  83  may be flared or extend radially outwardly of the spacer  79  as shown in dotted outline at  97  to have a larger diameter than the spacer  79  such as to cooperate with the slab material to retain the device  78  in the slab  94 .  
      Whilst the spacer  79  is shown to have an external wall  80 , the wall  80  may be reduced in size so that the spacer is of generally disc-like form and accordingly positions the body  83  in use adjacent to one side of the slab  94 . Alternatively, the wall  80  may be extended in width to position the body  83  further within the slab  94 .  
      FIGS.  23  to  26  illustrate a further embodiment of fire barrier device  98  according to the invention which in this case includes a sleeve-like body  99  which has a wall  100  having a number of outward steps and which terminates in an annular flange  101 , the body  99  suitably being formed of a plastics material. Supported on one stepped portion or shoulder  102  of the wall  99  is a ring  103  of heat expandable material, the ring  103  having a curved outer wall and being self-supporting and being moulded from a material comprising or containing intumescent material as described above to be of a relatively rigid construction. The wall portion  104  of the body  99  inwardly of the ring  103  is relatively thin for a purpose which will hereinafter become apparent. The wall  100  of the body  99  at its upper end  105  has an internal diameter which is substantially the same as a duct or pipe to be received in the body  99  whilst the internal diameter of the wall portion  104  is greater than the diameter of the pipe or duct again for a purpose which will hereinafter become apparent.  
      The device  98  is used in a similar manner to that described above with the flange  101  being secured by cleats or nails  106  to formwork  107  as shown in  FIG. 25  and a pipe or duct  108  inserted into the body  98  to be gripped by the upper end  105  of the body  99  to be supported in an upstanding attitude. To form the slab, concrete or other settable material  109  is applied to the formwork  107  to form the slab  110 , the formwork  107  being removed after curing or setting of the material  109 . The device  98  remains in situ within the slab  109  as shown in  FIG. 26  being held therein due to the configuration of the ring  103  of intumescent material which a diameter greater than the lower adjacent portion of the wall  100  to define a region  111  which fills with the settable material. The pipe  108  may be connected to a further pipe  112  having a female socket in the space between the wall  104  and pipe  107 .  
      Again in this embodiment in the event of fire, the heat applied to the ring  103  of intumescent material from the underside of the slab  110  will cause the ring  103  to expand with the expansion forces being concentrated radially through interaction with the surrounding slab material  109 . This is further concentrated by the convex outer surface of the ring  103  as indicated by the arrows in  FIG. 26  to rapidly close over the softening pipe  108  (and  112 ).  
      In the embodiment shown in FIGS.  23  to  26 , the ring  103  of intumescent material is a separate component such that the sleeve-like body  99  may be used for other purposes but may be converted for use in the applications described above. In other embodiments however, the body  99  and ring  103  may be formed integrally such as by moulding from a material including or consisting of intumescent material as referred to previously.  
      If desired, the sleeve-like body  99  may have at its upper end  105  an internal annular recess for engagement by a puddle flange of conventional form which locates about a penetrating pipe  107 .  
      As with the previous embodiments, the devices  78  and  98  are preferably installed within a slab, however they may be secured to one or both sides of a slab and around a service line or pipe extending through the slab or in a ceiling space. In the latter installation, the device  78  or  98  may be secured to a plasterboard ceiling panel with an enlarged opening being formed in the panel in alignment with the device  78  or  98  such that a pipe  90  or  108  supported by the device  78  or  98  may be secured to a further pipe through a female socket on the end of the further pipe which locates within the enlarged opening and enlarged axial bore in the device  78  or  98 . The device  78  or  98  will function in the same manner as that described above to shut over the lines of pipes in the event of fire.  
      Unlike the prior art devices, the intumescent material of the devices of the invention is self-supporting within or out of a slab. When installed within a slab, the intumescent material from which the heat expandable bodies of the devices are formed may form a mechanical and/or chemical bond with the material of the slab to further assist in retention of the bodies within the slab. The devices additionally are highly resistant to weather conditions, moisture or other adverse environments. Further whilst the devices are preferably of circular cross section, they may be of square cross sectional form or of any other cross section. Of course, the devices and the bores therein may be varied in size to suit the application and the size of pipe, duct or conduit with which the devices are to be used.  
      Whilst the devices commonly may be used in connection with formwork which is removed after moulding of a slab, they may be used in connection with formwork which remains in situ after slab moulding for example metal decking which defines formwork for forming of the slab. In this case, the metal decking may need to be cut out at the required locations where pipes are required to penetrate the slab, the devices of the invention being mounted in alignment with the cut out portions so that the pipes or ducts passing through the devices can pass through the cut out portions of the decking. When used with this type of formwork, the devices are usually secured in position by suitable metal fasteners. Further to prevent the pipes upstanding from the devices falling through the cut out portions of the decking during moulding of the slab, the devices may be provided with stop members. A typical configuration of stop member  113  is shown in  FIG. 4 , the stop member  113  simply comprising a strap extending diagonally of the device and being secured at opposite ends to the device and being removable therefrom after slab moulding.  
      Whilst the above has been given by way of illustrative embodiment of the invention, all such variations and modifications thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of the invention as herein defined in the appended claims.