Abstract:
A fire sprinkler head anti tamper canopy discourages hanging objects from a sprinkler head, or otherwise tampering or accidentally activating a sprinkler head. The canopy encloses the projecting portion of a sprinkler head, at least around the sides of the sprinkler head, and allows heat to enter and activate the sprinkler head, and water to escape from the sprinkler head for fire suppression. The canopy is magnetically secured to the wall or ceiling surface, without a requirement for physical attachment to the sprinkler head. Upon sprinkler head activation, water pressure dislodges the canopy, the latter returnable to an anti-tamper position once the fire sprinkler system has been reset.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention relates to a system and method for reducing the incidence of tampering with automatic fire sprinkler assemblies, and in particular, sprinkler heads. 
       BACKGROUND OF THE INVENTION 
       [0002]    Over the last fifty years, at least, automatic fire protection systems have become widely employed in various facilities throughout the world as a means to save lives, and to limit damage to physical property in the event of a fire. The design of the components associated with these systems has evolved during this time, and a significant number of different sprinkler head trigger configurations have evolved. These designs typically include a flow valve whose operation is initiated by varying mechanical methods, each of which are responsive to heat. 
         [0003]    These varying trigger configurations are activated in response to a predetermined amount of heat, or heat load. When the trigger is subjected to a predetermined heat load, the rigidity of a trigger component is compromised. This trigger component typically takes the form of a fusible link assembly, or a frangible bulb assembly, within the sprinkler head. When the rigidity of the trigger assembly is compromised by heat, it collapses and the sprinkler head valve is opened, thereby allowing the flow of water through the sprinkler head assembly, at a predetermined flow rate, into the building. The sprinkler head assembly may be either surface mounted, partially recessed, or fully recessed. An escutcheon or cover plate is typically used as an aesthetic surface trim piece at the perimeter of the hole in the wall, ceiling or ceiling surface through which the head assembly projects. 
         [0004]    Significant financial losses have been sustained by building owners or occupants as a result of tampering with sprinkler head assemblies. This loss most often occurs when an attempt is made by the occupant to use the exposed sprinkler head assembly as a device from which to hang various personal articles, as with a clothes hanger. In particular, most designs incorporate a bail or loop of metal which serves to protect the head from physical impact, and may also form part of the trigger structure. From the perspective of an unknowing or unconcerned person, the bail structure appears to be a convenient hook for a hanger, particularly for airing out or drying wet garments. 
         [0005]    As a result of this action by the occupant, the fusible link assembly may become inadvertently dislodged or broken, and consequently water flows through the sprinkler head assembly. The pressure and or flow rate from a sprinkler line is usually much greater than from drinking water supply lines, and thus a very large quantity of water may be discharged inside the building within a relatively short period of time. 
         [0006]    This action typically causes significant water damage to the flooring, floor covering, furniture, finishes and fixtures within the affected space, necessitating replacement of those damaged items and materials. In addition, the affected space may include floors beneath the discharged sprinkler line. All of the affected space may not be usable until repaired, representing lost rents or revenue, business interruption losses, and diminished productivity. Additionally, the discharge may also require the replacement of portions of the sprinkler head assembly and a resetting of the sprinkler system by qualified technicians, together with testing and reporting, all at considerable expense. Moreover, unless timely notified of a false alarm, fire rescue and other emergency personnel may respond to an automatic signal transmitted as a result of the sprinkler head activation, incurring costs to the municipality, and possibly the building owner. 
         [0007]    A cover for a sprinkler head is disclosed, for example, in International Application PCT/DE2006/000538 to Schnell, for use with a concealed sprinkler head. In Schnell, a cover is ejected by a bimetal strip in the presence of heat. Fully recessed sprinklers, as are disclosed in Schnell, are not as prone to tampering by hangers and the like. Thus, Schnell does not disclose a solution for tampering with exposed sprinkler heads. 
         [0008]    Another cover is disclosed in U.S. Pat. No. 3,998,273 to Juliano, again for a recessed head. Juliano provides, instead of the bimetal of Schnell, a magnetic engagement for the cover, where the magnet is retained by glue which melts in the presence of an amount of heat sufficient to activate the sprinkler head. 
         [0009]    Thus, Schnell and Juliano provide a cover for sprinkler heads for aesthetic purposes and not to prevent tampering, and are limited to recessed sprinkler head designs. Moreover, each design requires a release mechanism which increases the cost of the device. In addition, the covers, release mechanisms, and attachment means of Schnell and Juliano are integrated into the sprinkler head apparatus. That is, they are installed together with the sprinkler head, and thus are not installable without shutting down the sprinkler system, draining it, physically replacing the heads, and rearming the system. This can be a time consuming and expensive process, which leaves the facility unprotected against fire until all heads can be replaced. Many building require hundreds or thousands of heads, and thus replacing heads is simply not a viable option. 
         [0010]    To further discourage or reduce the incidence of tampering, it is desirable to notify a prospective tamperer of the potential danger of their actions. An alarm mechanism is disclosed in International Application PCT/GB01/03775, which provides for the breaking of an electrical connection upon melting soldered connections which secure a cover. This device is not directed to tampering, however, but rather to notify that the cover circuit has melted, indicating a fire. Moreover, the alarm signal is received only at a central location, not near the sprinkler head, and does not signal an undesired condition until it is too late. In addition, this device is also integrated or incorporated into the sprinkler head design. 
         [0011]    Accordingly, a need remains for a device which will notify an individual not to tamper with a sprinkler head. Further, it is desired to have a tamper deterring device which works with exposed heads, which are more likely to be tampered with, particularly by a hanger, than recessed heads. In addition, there remains a need for an anti tamper device which can be added to existing fire sprinkler systems without a need for replacing sprinkler heads, shutting down the sprinkler system, or performing any other labor intensive modifications. 
         [0012]    The art described in this section is not intended to constitute an admission that any patent, publication or other information referred to herein is “prior art” with respect to this invention, unless specifically designated as such. In addition, this section should not be construed to mean that a search has been made or that no other pertinent information as defined in 37 CFR § 1.56(a) exists. 
       SUMMARY OF THE INVENTION 
       [0013]    The invention provides for discouraging and thereby reducing the incidence of tampering with fire safety equipment, and in particular, with exposed sprinkler heads. In accordance with the invention, the device serves as a deterrent by obscuring the sprinkler head from view, and in addition, the sprinkler head cannot be misused without removal of the device itself. 
         [0014]    In accordance with an embodiment of the invention, a mesh or woven cover or canopy sized to enclose an exposed portion of a sprinkler head is provided with an engagement flange. The canopy has at least one open end, and in one embodiment, has an open end, enclosed sides, and a closed end. An attachment plate, in one embodiment a plate having the shape of a ring having a diameter corresponding to the diameter of the canopy, is attached to the wall or ceiling surface (“surface”) adjacent to the sprinkler head. A magnet is attached to either the flange or plate, whereupon the other of the two parts includes a magnet or magnetically active material, such as a ferromagnetic material. In this manner, the canopy is releasably magnetically retained upon the adjacent surface. Due to the open weave or aperture of the canopy, heat may readily enter the canopy and activate the sprinkler head as intended. When the sprinkler head is activated, discharged water engages the mesh or body of the canopy, and or a plate disposed at a closed end of the canopy, and by action of the water pressure, the canopy is pushed away, breaking a magnetic bond which is configured to be weak relative to the force of released water. The ready admission of heat, combined with a quick release of the canopy, ensures no impact to the performance of the fire suppression system. 
         [0015]    The mesh size, or aperture size within the canopy is selected to advantageously visibly obscure the sprinkler head, reducing a temptation to use the sprinkler head for an improper purpose. Concomitantly, the mesh or aperture size must be large enough to avoid adversely impacting the performance of the sprinkler head, and more particularly, must not introduce a measurable or significant delay in activation. 
         [0016]    In a typical sprinkler head installation, a standard escutcheon ring is installed during construction, to cover the cut or exposed surface through which the sprinkler head projects. In accordance with the invention, the attachment plate is sized to surround this escutcheon, enclosing it within the canopy. In one embodiment, the escutcheon may be omitted, reducing construction costs, and the attachment flange and canopy may be sized correspondingly smaller. A canopy mesh size may be selected to visually obscure an exposed wall surface within the canopy, while adequately admitting heat. 
         [0017]    In another embodiment, a device in accordance with the invention is attached to the escutcheon itself, either magnetically, or through an adhesive layer as otherwise described herein, with respect to attachment to the surface. 
         [0018]    In accordance with the invention, the attachment plate is adhered to the ceiling by adhesive applied to the surface contacting side thereof. Alternatively, double sided adhesive tape or foam may be applied to either the attachment plate or surface, after which the attachment plate is bonded to the surface. The double sided tape or foam can be applied in a factory production process, or applied at the installation site. In either event, the unattached adhesive side or sides have a protective release layer, which is removed prior to application. Alternatively, during new construction in particular, the attachment plate may be adhered to the ceiling when same is wet and curing, or through the application of liquid glue to the plate, the surface, or both. Further, the attachment plate, or discrete members as described below, may be attached to the surface using any known means, including screws, rivets, nails, or any other known form of bonding. 
         [0019]    In one embodiment, the attachment plate is a plastic or metallic ring with magnetic material bonded or otherwise affixed thereto. Alternatively, the attachment plate may be a ring shaped magnet, or ring of magnetized material. Where the canopy engagement flange contains magnetic material, the attachment ring may merely be magnetically active, for example containing a ferrous material. Both the engagement plate and the attachment ring may alternatively be magnetic, however in this embodiment the respective poles must be appropriately aligned on each surface in order to produce an attraction therebetween. 
         [0020]    While the canopy is described as being meshed, it should be understood that slits or other aperture shapes may be provided in the canopy surface, provided that there is sufficient passageway for heat, and thus sprinkler activation. 
         [0021]    Moreover, while the canopy is advantageously manufactured in a round shape, such as a cylinder or conical frustum (as illustrated in the figures), a pyramidal frustum, cylinder, or other shape which is sized and shaped to at least partially surround the sprinkler head, or is otherwise shaped to shield and impede access to the trigger, may be used, and is therefore contemplated as within the scope of the invention. 
         [0022]    Similarly, the attachment plate is provided with a shape complementary to the canopy engagement flange. Further, the attachment plate may be composed of a plurality of discrete elements which are separately attached to the surface, thereby reducing the total amount of material needed. In this event, a template may be provided to facilitate attachment, or alternatively, the discrete attachment member parts may be magnetically connected first to the engagement flange, and subsequently adhered or attached to the surface after being thus properly aligned. 
         [0023]    In accordance with a further embodiment of the invention, an electronic sound generating device is connected to the canopy, operative to respond to a movement of the canopy. The sound generating device emits an alarm noise, or plays a recorded message in at least one language, notifying individuals proximate the canopy not to move or remove the canopy from its installed location. The message may further warn of the rationale or consequences of a failure to heed the warning. In addition, the message may repeat until the device is replaced in its correct location. Detection of replacement or removal of the device may be by a magnetic switch, mechanical switch, or other means as known in the art. 
         [0024]    In addition to, or in place of an audible message, a signal may be sent to a central administration site, as by wired or wireless transmission, whereby persons responsible for maintenance or safety can ensure that the canopy is replaced, or that further measures may be taken to ensure that the sprinkler system is not tampered with further. 
         [0025]    In accordance with another embodiment of the invention, written indicia, either symbolic or in at least one written language, are provided in a prominent visible location on the canopy. The indicia may warn not to remove the canopy, or may warn of the consequences and or potential penalty for removing the canopy. 
         [0026]    As noted above, in one embodiment of the invention, a plate or cup is provided at and end of the canopy distal from the surface. This surface may further serve to providing a location for written indicia or symbols, as well as to provide an aesthetic role, structural rigidity, or as an aid to manufacturing. 
         [0027]    As discussed above, covers for fully recessed sprinkler heads are known, but these are not suitable for projecting sprinkler heads, and they further require additional means for conducting heat, and for dislodging the cover, that are cooperative with and dependent upon the particular physical design of the sprinkler head being deployed. Moreover, recessed sprinkler heads are not as vulnerable to tampering as exposed heads, and thus covers for recessed heads are not directed to or adapted to the problem of reducing the incidence of tampering. 
         [0028]    As can be seen from the figures and the description, the canopy of the present invention is operative to deter tampering with a sprinkler head regardless of its design, and without a requirement for physical configuration or conformity with an existing sprinkler head. Thus, a canopy in accordance with the invention may be rapidly and easily added to an existing sprinkler system, without modification to the latter, and without requiring that an existing system be shut down or disturbed. 
         [0029]    The canopy may be removed for testing or maintenance by authorized persons without a requirement for tools, and without adding significantly to the amount of time required to complete such a task. In this event, in accordance with the invention, switching means are provided to turn off an audible or remote alarm prior to removing the canopy. Switching may be by any known means, including a keyed or magnetic switch located on or within the canopy, or by disabling a remote alarm associated with one or more devices to be tested or maintained. 
         [0030]    The invention works to prevent tampering by various modalities, in recognition of various tamperer intentions, as follows: 
         [0031]    Tamperer  1 /Concealment 
         [0032]    Initially, there are potential tamperers who may not realize what a sprinkler head is, and may innocently and unknowingly connect or hang an object from a sprinkler head, and thus accidentally activate the sprinkler head, as by moving or dislodging a fusible link or bulb which maintains the sprinkler head in a sealed condition. By obscuring the sprinkler head, the present invention prevents a potential tamperer from viewing a possible attachment location, or from availing themselves of the attachment location. Accordingly, no attempt is made to use the sprinkler head as a point of attachment, and the sprinkler head is not accidentally activated. 
         [0033]    Tamperer  2 /Physical Act Requirement 
         [0034]    Some individuals may become aware that a sprinkler head is concealed by a canopy in accordance with the invention, either by looking through the bottom of an embodiment without a bottom panel, or through recognition that a sprinkler head is likely to be under the canopy. If these individuals nonetheless wish to hang an object from the sprinkler head, they will first need to physically remove the canopy. Initially, they may be unaware that it is removable, and would thus be discouraged altogether. In all events, however, they must decide to deliberately tamper with an object which, as should be clear to a reasonable person, is not meant to be disturbed. Most individuals would, out of respect for private property and propriety, decide not to remove the canopy. 
         [0035]    Tamperer  3 /Warning Messages 
         [0036]    Many individuals would heed a written warning, or alternatively an internationally recognized symbol, indicating that an object should not be touched or tampered with. Additionally warnings, such as legal penalties, may also be written upon or attached to the canopy. This additional aspect of the invention would discourage another segment of the population. 
         [0037]    Tamperer  4 /Potential Alarm or Activation 
         [0038]    Individuals who would, despite the previous deterrents, continue to consider removing the canopy, might also consider the possibility that the device is alarmed, or alternatively, that removal of the canopy would precipitate activation of the sprinkler head. In addition, written warnings or markings may specifically warn of an alarm, or possible activation of the sprinkler head, as well as the potential consequences of these events. Thus, a further segment of the population would be dissuaded by these factors. 
         [0039]    Tamperer  5 /Alarm or Warning Activation 
         [0040]    It is within the scope of the invention to activate an audible warning as the canopy is moved only a limited amount, and not yet detached from the mounting surface. In this manner, a startled potential tamperer may discontinue attempts to remove the canopy. A canopy in accordance with the invention could be configured to trigger a remote alarm upon such mere movement, as otherwise described herein. 
         [0041]    Ultimately, however, a tamperer may remove the canopy, at which point, in accordance with the invention, a central desk or security officer is instantly notified by wired or wireless communication. In such an event, the tamperer&#39;s identity could become known, either by one or more cameras, or by being deduced based upon limited access to the sprinkler head, e.g. occupants of a hotel room. Aware of the possibility of being discovered, many individuals would stop tampering with the sprinkler head upon hearing the first audible alarm or recorded spoken warning. 
         [0042]    Ultimately, however, a deliberate vandal may continue, at which point it is still possible for security personnel to arrive at the sprinkler head location before the sprinkler head is actually activated. Regardless of whether activation of the sprinkler head occurs, early warning made possible by the invention improves the likelihood that responsible individuals may be apprehended, and thus the invention serves to discourage tampering in the future. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0043]    A more complete understanding of the present invention, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein: 
           [0044]      FIG. 1  depicts a canopy in accordance with the invention, mounted on a wall, positioned over a projecting sprinkler head; 
           [0045]      FIG. 2  shows the canopy of  FIG. 1 , mounted on a ceiling; 
           [0046]      FIG. 3  depicts a canopy embodiment in accordance with the invention, including alternative mounting means, and indicia; 
           [0047]      FIGS. 4A-4C  illustrate alternative means of mounting a canopy in accordance with the invention; 
           [0048]      FIG. 5  depicts an alternative canopy in accordance with the invention, including means for communicating removal and replacement of the canopy to a central location; 
           [0049]      FIG. 6  depicts another alternative canopy in accordance with the invention, including heat conducting apertures, audible means for notification of movement, and means for securing a magnetically charged element; 
           [0050]      FIG. 7  depicts a further alternative canopy in accordance with the invention, having an open bottom. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0051]    In the description which follows, any reference to direction or orientation is intended primarily and solely for purposes of illustration and is not intended in any way as a limitation to the scope of the present invention. Also, the particular embodiments described herein are not to be considered as limiting of the present invention. 
         [0052]    Referring now to the figures, in which like reference numerals refer to like elements, the invention provides for discouraging and thereby reducing the incidence of tampering with fire safety equipment, and in particular, with exposed sprinkler heads  200 , 202  (hereinafter  200 ), as shown in  FIGS. 1 and 2 . In particular, sprinkler head  200  is obscured from view, and in addition, cannot be misused without removal of the device itself. A common form of misuse is the hanging of objects, such as garments on a hanger, from the sprinkler head bail arm  204  or other potential hanger support, including portions of the trigger assembly  206 . 
         [0053]    The invention is directed to sprinkler heads  200  in which a valve is held shut by a thermal linkage, such as linkage  214 . The invention may be employed with all types of sprinkler heads, including conventional, horizontal sidewall, vertical sidewall, upright, pendent, and recessed pendent. The sprinkler head is activated normally by a weakening of thermal linkage  214  in the presence of heat. Typically, after 3 or 4 minutes of exposure to a predefined level of heat, the thermal link will collapse and release a cap, diaphragm or valve, whereupon water may be discharged. Shorter duration thermal linkages also exist. Activation through tampering, however, typically occurs due to the thermal link being moved out of place, or moved to the point of breakage. 
         [0054]    In accordance with an embodiment of the invention, and with reference to  FIGS. 1-2 , a mesh or woven cover or canopy  100 , sized to substantially surround or enclose an exposed portion of a sprinkler head  200 , is provided with an engagement flange  102 . To effectively impede activation through tampering, it is sufficient for the enclosure to at least substantially block or impede access to the trigger, usually accessed from the side of the sprinkler head. Canopy  100  has at least one open end  104 , and in one embodiment, includes an open end  104 , enclosed sides  106 , and a closed end  108 . A mounting or attachment plate  110 , in one embodiment a ring shape having a diameter corresponding to the diameter of the canopy, is attached to surface  208 , 210  (hereinafter  210 ), wherein surface  208  is illustrative of a vertical wall surface, and surface  210  is illustrative of a horizontal ceiling surface, adjacent to sprinkler head  204 . A magnet  112  is attached to either flange  102  or plate  110 , whereupon the other of the two parts includes a magnet or magnetically active material, such as a ferromagnetic material. In this manner, the canopy is releasably retained upon the adjacent surface  210 . 
         [0055]    It should be understood that a variety of possible combinations of fastening or affixing means exist, within the spirit and scope of the invention, for releasably retaining canopy  100  upon surface  210 . With reference to  FIGS. 4A-C , it can be seen that plate  110  is affixed to surface  210  using screw  114 . Any known fastener, such as a nail, pin, rivet, or any other known form of bonding, may be used to attach plate  110  to surface  210 . As shown in  FIG. 4B , either or both of plate  110  and flange  102  are magnetized, and are mutually attracted with no other intervening layers. If only one of plate  110  and flange  102  are magnetized, the other is magnetically active. 
         [0056]    In an additional embodiment in accordance with the invention, hook and loop fasteners may be substituted for magnetized or magnetically active elements, as described herein. In this embodiment, either hook material or loop material is attached, as by adhesive or other means, to plate  110 , and the complementary material is attached to flange  102 . It is important, as it is with a magnetic attraction, to ensure that the attachment force is sufficient to retain canopy  100  in place, yet does not hinder release of the canopy in the event of sprinkler activation. 
         [0057]    In accordance with an alternative embodiment of the invention, and with reference to  FIG. 4A , attachment plate  110  is adhered to surface  210  by an adhesive layer  116  interposed between plate  110  and surface  210 . Adhesive layer  116  may be provided in the form of double sided adhesive tape or foam, applied to either attachment plate  110  or surface  210 , after which attachment plate  110  is bonded to surface  210 . Adhesive layer  116  may be applied in a factory production process, or applied at the installation site. In both configurations, the unattached adhesive side or sides may be provided with a protective release layer, such as a wax or polymer coated paper (not shown), which is removed prior to application. 
         [0058]    An additional adhesive layer  118  may be applied to plate  110 , as shown in  FIG. 4A , or may alternatively be applied to flange  102 , and magnet  112  may then be adhered to adhesive layer  118 . 
         [0059]    In accordance with yet another embodiment of the invention, any of the aforementioned adhesive layers, such as layer  116 , may include a heat sensitive adhesive composition, wherein the layer loses gripping strength in the presence of heat at a temperature equal to or below that of the sprinkler head trigger. This embodiment operates to further ensure separation of the canopy in the event of a fire. 
         [0060]    In a further alternative in accordance with the invention, an adhesive layer, such as layer  116 , is provided in the form of microcapsules or other composition which enables canopy  100  to be easily and effectively removed and reapplied repeatedly, through separation of the adhesive layer. 
         [0061]    Magnet  112  may also be affixed to flange  102  or plate  110  through known mechanical means, including a mechanical enclosure, as is shown in  FIG. 6 . 
         [0062]    In another alternative, during new construction in particular, attachment plate  110  may be adhered to the ceiling when same is wet and curing, or through the application of liquid glue to plate  110 , surface  210 , or both. 
         [0063]    In another embodiment, a device in accordance with the invention is attached to escutcheon  212 , either magnetically, or through an adhesive layer as otherwise described herein, with respect to attachment to the surface. 
         [0064]    Due to the open weave of the canopy, or through at least one sufficiently sized aperture, heat may readily enter the canopy and activate the sprinkler head as intended. When the sprinkler head is activated, discharged water engages the mesh  120  of the canopy, and or a plate disposed at a closed end  108  of canopy  100 , and by action of water pressure, canopy  100  is pushed away, breaking a magnetic bond which is configured to be weak relative to the force of released water, and releasing the canopy from the surface, as described above. The ready admission of heat, combined with a quick release of the canopy, ensures no significant impact to the performance of the fire suppression system. 
         [0065]    It should be understood that only a portion of mesh  120 , shown in  FIGS. 3 and 5 , is illustrated, and that additional areas of mesh extend along sides  106  and or bottom  108  of canopy  100 . All or a portion of canopy  100  may be fabricated of mesh  120 , except as otherwise provided herein. Mesh  120  may be formed of a variety of materials, including plastic, wire, stainless steel, stainless steel wire, metalized plastic, injection molded plastic, galvanized metal, or other metal. The aperture size of mesh  120  is selected to advantageously visibly obscure sprinkler head  200 , reducing a temptation to use sprinkler head  200  for an improper purpose. Concomitantly, the aperture or mesh  120  size must be large enough to avoid adversely impacting the performance of the sprinkler head, and more particularly, must not introduce a measurable or significant delay in activation. The mesh size is further chosen in consideration of factors affecting separation of canopy  100  from surface  210 . These include the amount of water pressure impacting mesh  120 , the overall surface area of mesh  120 , and if present, bottom  108 , the strength of the magnetic attachment, and the speed with which it is desired to dislodge canopy  100 . Mesh aperture sizes in a range of about 0.015 to 0.030 inches are provided in a typical embodiment, although larger or smaller apertures may be provided based upon, at least, the factors listed. 
         [0066]    A canopy in accordance with the current invention may be provided in a variety of sizes, depending in part upon the factors for separation described above, and the extent to which the sprinkler head extends from or protrudes through surface  210 . In a sprinkler configuration where sprinkler head  200  extends 2 inches from surface  210 , a canopy advantageously has a length of 3 inches, a width of 3 inches proximal to surface  210 , and a width of 2 inches distal to surface  210 . In this illustrative embodiment, engagement flange has a width of one quarter inch. Similarly, plate  110  has a matching width of at least one quarter inch. Larger or smaller sprinkler heads, or larger or smaller sprinkler head protrusions, would indicate a commensurate change in dimensions, so that there is adequate passage of heat for activation, and timely separation in the event sprinkler head  202  is triggered, as described. Dimensions are, of course, different for each of the varied canopy shapes. It is desirable for the canopy to be sized so that a tamperer does not have ready access to trigger  214  of sprinkler head  202 . In particular, dimensions are selected wherein access to trigger  214 , as by fingers or the hook of a clothes hanger, is impeded sufficiently to dissuade misuse or tampering with the sprinkler head. 
         [0067]    While the canopy is meshed in one embodiment, it should be understood that slits  120 A or other aperture shapes may be provided in the canopy surface, provided that consideration of the factors described above, for mesh, are considered in determining the optimum quantity, location, and size of apertures. There must be sufficient passageway for heat, and thus sprinkler activation, as well as sufficient surface area to engage discharged water and thus dislodge canopy  100 . 
         [0068]    A variety of materials can be used in the construction of canopy  100 , including plastic, metal, or composites. For an attractive finish, stainless steel or vacuum metalized plastic may be used. In humid or corrosive atmospheres, a corrosion resistant material, such as plastic, stainless steel or galvanized metal, is advantageous. A canopy  100  in accordance with the invention may also be painted or camouflaged using any known means, provided apertures in mesh  120  or slits  120 A are maintained unobstructed. 
         [0069]    In a typical sprinkler head installation, escutcheon  212 , usually ring shaped, covers the cut or exposed surface through which sprinkler head  200  projects. In accordance with the invention, attachment plate  110  is sized larger than escutcheon  212  in order to surround same, enclosing it within canopy  110 . The invention thus enables escutcheon  212  to be omitted, reducing construction costs. Canopy mesh  120  size may be selected to visually obscure an exposed wall surface within the canopy, while adequately admitting heat. 
         [0070]    In one embodiment, attachment plate  102  is a plastic or metallic ring with magnetic material  112  bonded or otherwise affixed thereto. Alternatively, attachment plate  102  may be a ring shaped magnet, or ring of magnetized material. Where engagement flange  102  contains magnetic material, the attachment ring may merely be magnetically active, for example containing a ferrous material. Both engagement plate  102  and attachment plate  102  may alternatively be magnetic; however in this embodiment the respective poles must be appropriately aligned on each surface in order to produce an attraction therebetween. 
         [0071]    Moreover, while canopy  100  is advantageously manufactured in a round shape, such as a cylinder or conical frustum (as illustrated in the figures), a pyramidal frustum or other shape which is sized to enclose sprinkler head  200  may be used, and is therefore contemplated as within the scope of the invention. 
         [0072]    Similarly, attachment plate  110  is provided with a shape complementary to canopy engagement flange  102 . Further, the attachment plate may be composed of a plurality of discrete elements  110 A which are separately attached to the surface, thereby reducing the total amount of material needed. In this event, a template (not shown) may be provided to facilitate attachment, or alternatively, the discrete elements  110 A may be magnetically connected first to engagement flange  102 , and subsequently adhered or attached to surface  210  after being thus properly aligned. 
         [0073]    In accordance with a further embodiment of the invention, an audible device  122  is connected to the canopy, operative to respond to a movement of canopy  100 . The sound device  122  emits an alarm noise, or plays a recorded message in at least one language, notifying individuals proximate the canopy not to move or remove the canopy from its installed location. Sound device  122 , in one embodiment, is an electronic circuit  128  including power supply means  124  and a sound transducer  126 . Electronic circuit  128  is responsive to movement of the canopy, as by incorporation of means for detecting motion  130 , or through interaction with a switch  138  engaged through proximity with, or contact with, plate  110 . The message may further warn of the rationale or consequences of a failure to heed the warning. In addition, the message may repeat until the device is replaced in its correct location, or a specified time has elapsed. Detection of replacement or removal of the device may be by switch  138 , or other means known in the art. 
         [0074]    It should be understood that, in accordance with the invention, it is advantageous for the audible warning to be given as soon as canopy  100  is moved even slightly, before it is yet removed from its mounting. Thus, a potential tamperer may be encouraged to abandon an attempt while canopy  100  is still attached. This may be accomplished, for example, through the inclusion of a motion sensor (not shown). 
         [0075]    In addition to, or in place of an audible message, a signal may be sent to a central administration site, as by wire  140  or wireless  132  transmission, whereby persons responsible for maintenance or safety can ensure that canopy  100  is replaced, or that further measures may be taken to ensure that the sprinkler system is not tampered with further. Advantageously, wireless communication could utilize the same computer wireless LAN as may be found in many hotels or office buildings, wherein electronic circuit  128  includes means for transmitting a signal through the wireless local area network (LAN) to central administration, including identifying information for the particular canopy or location. A cellular telephone network, or a simple radio network could similarly be employed. 
         [0076]    Alternatively, individual canopies  100  may be wired directly to a central location, or may be connected by wire  140  to satellite relay devices (not shown) which connect by wire or wireless connection, as described. By reducing the number of communication devices required, costs could be reduced. 
         [0077]    In a further alternative in accordance with the invention, each canopy  100  is provided with a low cost, low power, short distance radio transponder  128 , 132 , which relays a tamper signal to a relay or satellite device, the latter communicating over a longer distance network, such as the LAN network described, a wide area network (WAN), or the internet, or though a telephone, satellite, or cable network. 
         [0078]    In accordance with another embodiment of the invention, written indicia  134 , either symbolic  136  or in at least one written language, are provided in a prominent visible location on canopy  100 . The indicia may warn not to touch or remove the canopy, or may warn of the consequences and or potential penalty for removing the canopy. 
         [0079]    As noted above, in one embodiment of the invention, a plate or cup  108  is provided at one end of the canopy, distal from the surface. This surface may further serve to providing a location for written indicia or symbols, as well as to provide an aesthetic role, structural rigidity, or as an aid to manufacturing. Cup  108  further serves as a solid base upon which to support and conceal electronic components. 
         [0080]    In an alternative embodiment in accordance with the invention, and with reference to  FIG. 7 , canopy  100  has two open ends,  104 , 104 A, as indicated by arrow “A”. To increase resistance to discharged water, sufficient to ensure separation of canopy  100  from surface  210 , sides  106  may advantageously be provided with a greater taper than is provided for embodiments having a closed end  108 , or a reduced mesh  120  or aperture  120 A size. Moreover, to further discourage tampering, opening  104 A is sized sufficiently small to render difficulty in accessing the sprinkler head within, particularly with respect to admitting fingers or a hanger hook. 
         [0081]    All references cited herein are expressly incorporated by reference in their entirety. In addition, unless mention was made above to the contrary, it should be noted that all of the accompanying drawings are not to scale. There are many different features to the present invention and it is contemplated that these features may be used together or separately. Thus, the invention should not be limited to any particular combination of features or to a particular application of the invention. Further, it should be understood that variations and modifications within the spirit and scope of the invention might occur to those skilled in the art to which the invention pertains. Accordingly, all expedient modifications readily attainable by one versed in the art from the disclosure set forth herein that are within the scope and spirit of the present invention are to be included as further embodiments of the present invention.