Abstract:
A safe haven wall for use in defining a safe haven in an underground mine comprising a lower section and an upper section, wherein said upper section is slidingly engaged to the lower section.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to and benefit from, under 37 C.F.R. §1.119(e), U.S. Provisional Patent Application Ser. No. 62/081,114 filed on Nov. 18, 2014; U.S. Provisional Patent Application Ser. No. 62/120,606 filed on Feb. 25, 2015; and, U.S. Provisional Patent Application Ser. No. 62/250,657 filed on Nov. 4, 2015. All applications are hereby incorporated by reference. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable 
     REFERENCE TO A “MICROFICHE APPENDIX” 
     Not applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention pertains to the field of mine safety and more specifically the provision of safe havens in underground mines to provide safe refuge for miners unable to escape their work area immediately after a disaster due to toxic gases or a blocked escapeway. 
     2. General Background of the Invention 
     In many mining disasters in underground mines, many miners survive the initial disaster only to lose their lives due to an inability to escape from or isolates themselves from poisonous gases that build up in the mine in the wake of the disaster. For example, in 2006, there were three major mining disasters involving fire or explosion. In these events, 19 miners lost their lives despite surviving the initial disaster. 
     In the wake of these 2006 disasters, the MINER Act (Mine Improvement and New Emergency Response Act of 2006) was enacted. As part of the mandate of the MINER Act, NIOSH was charged with researching refuge alternatives to determine what alternatives would provide the best protection for miners following a disaster. The primary function of a refuge alternative is to provide a safe haven for miners unable to escape their work area immediately after a disaster due to toxic gases or a blocked escapeway. To be effective, a refuge alternative must, at a minimum, survive the initial disaster. In addition, it would be beneficial if the refuge alternative would protect the miners from any secondary explosions. This research considered both built-in-place and portable refuge chambers (i.e. safe havens). 
     The research concluded that built-in-place alternatives were highly preferable. Such alternatives provide a superior environment to miners using them for refuge, which can beneficial to the health of the miners following a disaster. Such built-in-place alternatives also provide the ability to deliver an unlimited supply of breathable air through a borehole or a protected compressed air line, examples of the latter being the Hubble® Breathable Air Units (Models HBA 75, HBA 100, and HBA 250) that have been approved by MSHA for such use. 
     In an April 2015 NIOSH report 1  focused on facilitating the use of built-in-place safe havens, the authors noted that there were approximately 30 built-in-place safe havens in use in underground coal mines in the U.S.; none of which were capable of being relocated as the working face is advanced. The ability to relocate the safe haven is, however, highly desirable to keep the safe haven within the preferred distance from the working face of the mine. But the benefits of a built-in-place safe haven are so great, a 2007 report to Congress in the wake of the MINER Act advised that, if a built-in-place safe haven is used, permitting extended distance from the working face should be considered despite the obvious additional risks this would pose to miners, especially injured miners, in getting to the safe haven before the air available through the miner&#39;s self-contained self-rescuer is exhausted. 1 NIOSH [2015]. Facilitating the use of built-in-place refuge alternatives in mines. By Trackemas J D, Thimons E D, Bauer E R, Sapko M J, Zipf R K, Schall J, Rubinstein E, Finfinger G L, Patts L D, LaBranche N. Pittsburgh, Pa.: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 2015-114, RI 9698. 
     Thus, it is clear that there is need for an apparatus that can be used to create the equivalent of a built-in-place safe haven in an underground mine that is also capable of being relocated as the working face of the mine advance. The present invention addresses this need. Unlike the known examples discussed above, the present invention is an adjustable height wall that can be assembled outside the mine and transported to the desired safe haven location at a lower cost than constructing a permanent wall in place. Once transported to the desired location in the mine, the wall of the present invention can be installed to create the equivalent of a built-in-place safe haven. Moreover, as the working face advances, the wall of the present invention can be relocated within the underground mine to keep the safe haven within the preferred distance from the working face. Thus, the present invention provides the equivalent of a built-in-place safe haven with all of the attendant benefits at a lower cost without the need to consider allowing it to be located further from the working face. 
     SUMMARY OF THE INVENTION 
     A safe haven wall for use in defining a safe haven in an underground mine comprising a lower section and an upper section, wherein said upper section is slidingly engaged to the lower section. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the attached figures, wherein like reference numerals denote like elements and wherein: 
         FIG. 1 —is a perspective view of an embodiment of the invention. 
         FIG. 2 —is a partially exploded perspective view of an embodiment of the invention. 
         FIG. 3 —is a partially exploded partial perspective view of an embodiment of the invention. 
         FIG. 4 —is a partially exploded partial perspective view of an embodiment of the invention. 
         FIG. 5 —is a perspective view of an embodiment of the invention. 
         FIG. 6 —is a partial perspective view of an embodiment of the invention. 
         FIG. 7 —is a partial perspective view of an embodiment of the invention. 
         FIG. 8 —is a perspective view of an embodiment of a base portion of the invention. 
         FIG. 9 —is a perspective view of an embodiment of a base portion of the invention. 
         FIG. 10 —is a perspective view of an embodiment of a base portion of the invention. 
         FIG. 11 —is a front view of an embodiment of a hatch portion of the invention. 
         FIG. 12 —is a cross-section view of the hatch portion of the invention from  FIG. 11 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention is safe haven wall  100  for use in underground mines to define an area within a mine in which miners and other personnel who are in the mine at the time of a catastrophic event such as an unplanned explosion or roof collapse can be safe when immediate egress is not possible. Safe haven wall  100  comprises lower section  200  and upper section  300 . Lower section  200  and upper section  300  preferably comprise separate fabrications that are brought together at the mine to facilitate the movement of safe haven wall  100 . One of the primary benefits of safe haven wall  100  is that it can be relocated within the mine after its initial installation or removed from the mine and installed in a different mine. 
     Lower section  200  comprises base plate  210 , vertical members  220 , angular base members  240 , sheathing panels  250  and opposing end portions  211 ,  213 . Base plate  210  may be formed from steel C-channel, where central portion  212  of the C-shape is placed adjacent to the mine floor across the opening to the safe haven and opposing end portions  211 ,  213  extend upwards. Defined in central portion  212  of base plate  210  are spaced apart apertures  214  to facilitate the bolting of base plate  210  to the mine floor across the opening to the safe haven or to base  120  if the additional height is required. The minimum spacing of apertures  214  is determined by the overall length and height of safe haven wall  100 . In any event, the spacing is selected to ensure safe haven wall  100  can withstand a static pressure of 15 pounds per square inch (“PSI”). In a particular non-limiting embodiment in which the length of safe haven wall  100  is from nineteen to twenty-one feet, it is preferable to provide and utilize at least 14 equally-spaced apertures  214  to secure lower section  200  to the mine floor. It is also advantageous to utilize additional apertures  214  near the end portions of lower section  200 . 
     In the illustrated embodiment, vertical members  220  are steel I-beams that extend upward from base plate  210 . Vertical members  220  are affixed such that outer surface  222  of vertical member  220  will be adjacent upright portion  216  of base plate  210  that faces outward (i.e. away from) the safe have when safe haven wall  100  is in place. When base plate  210  and vertical members  220  are steel, welding is one method that can be used to affix vertical members  220  to base plate  210 . 
     The spacing of vertical members  220  is selected based on the height of lower section  200  and the maximum overall height of safe haven wall  100  to ensure safe haven wall  100  can withstand a static pressure of 15 PSI. It is, however, preferable to space each pair of vertical members  220  to provide at least a 30-inch clear span to enable a stretcher to pass through the space between said pair of vertical members  220 . An exception to this spacing is for vertical members  220  at the opposing ends of lower section  200 . The height of vertical members  220  is less than the height of the mine ceiling at the desired construction location. In one embodiment, for use in a mine with a 51-inch ceiling, vertical members  220  are approximately 40 inches in height. Defined in the upper portion of vertical members  220  are apertures  224  that are parallel to safe haven wall  100  (where steel I-beams are used for vertical members  220 , apertures  224  are defined in the web of the I-beam). 
     Angular base members  240  are affixed to base plate  210  such that one angular base member  240  extends between each pair of vertical members  220 . In each case, upright portion  242  of angular base member  240  is adjacent to upright portion  216  of base plate  210  that faces outward (i.e. away from) the safe have when safe haven wall  100  is in place. Upright portion  242  of angular base member  240  has a height that is greater than upright portion  216  of base plate  210 . This configuration results in outer surfaces  244  of upright portions  242  of angular base members  240  cooperating with outer surfaces  222  of vertical members  220  to form a plane for affixing sheathing panels  250 . This also allows the edge portion of upright portion  216  of base plate  210  to function as a ledge upon which sheathing panels  250  can rest while it is being affixed to vertical members  220  and angular base members  240 . 
     In the illustrated embodiment, sheathing panels  250  are comprised of two different materials: steel (sheathing panels denoted as  250   s ) and polycarbonate (sheathing panels denoted as  250   pc ). Sheathing panels  250  for a single installation could, however, be all of single material, including steel or polycarbonate, provided said material is capable of being affixed to vertical members  220  and base members  240  and capable of withstanding a static pressure of 15 PSI. Sheathing panels  250  are preferably affixed to the outward facing sides of vertical members  220  and angular base members  240 . In the case of steel sheathing panels  250   s , said affixation is preferably accomplished through welding. 
     In the case of polycarbonate sheathing panels  250   pc , the panels may be affixed in a number of ways. One advantageous manner of attaching sheathing panels  250   pc  is the use of double-sided tape  252  such as 3M VHB Tape, which has the added benefit of forming an airtight seal. Another manner of affixing sheathing panels  250   pc  is with structural silicone (not shown) such as Tremco Spectrem 2, which also has the benefit of forming an airtight seal. 
     Instead of or as a supplement to the foregoing, sheathing panels  250   pc  may be affixed to vertical members  220  and angular base members  240  using bolts  258  that extend through apertures  256  that are held in place using nuts  260 . Washers  262  are preferably between the head of bolt  258  and the outer surface of sheathing panel  250   pc  to evenly distribute the pressure exerted by the head of bolt  258 . (Reference numbers  258 ,  260 , and  262 , are respectively used herein to identify bolts, nuts, and washers generally. One of skill in the art will, however, recognize that specific bolts, nuts, and washers may be selected for the various uses of bolts, nuts, and washers in connection with safe haven wall  100 .) 
     Upper section  300  comprises ceiling plate  310 , mating members  320 , overlap plate  350  and opposing end portions  311 ,  313 . Ceiling plate  310  may be formed from steel C-channel, where central portion  312  of the C-shape is placed adjacent to the mine ceiling across the opening to the safe haven and opposing end portions  311 ,  313  extend downwards. Defined in central portion  312  of ceiling plate  310  are spaced apart apertures  314  to facilitate the bolting of ceiling plate  210  to the mine ceiling. Apertures  314  may be aligned with apertures  214  in base plate  210 . In any event, the spacing is selected to ensure safe haven wall  100  can withstand a static pressure of 15 PSI. 
     Mating members  320  are affixed to ceiling plate  310  and located to mate with vertical members  220  of lower section  200 . In the illustrated embodiment, mating members  320  are formed from steel tubing have a generally rectangular cross section. The width of mating members  320  is selected to enable mating members  320  to slide within the channel of the I-beams used for vertical members  220 . For outer vertical members  220 , only a single mating member  320  is provided. For other vertical members, a pair of mating members  320  is provided. Where a pair is provided, mating members  320  forming the pair are spaced apart to accept the I-beam web of vertical member  220 . Each mating member  320  is provided with slots  324  defined in the wall of the tubing adjacent to vertical member that generally align with apertures  224  defined in vertical members  220 . 
     Overlap plates  350  are then affixed to the downward extending portion of ceiling plate  310  that faces outward (i.e. away from) the safe haven when safe haven wall  100  is in place. In the illustrated embodiment, overlap plates  350  are formed of steel. In such a case, welding is the preferred method of affixing overlap plates  350  to ceiling plate  310 . In alternate embodiments, other types of fixation may be required. Defined in overlap plates  350  are slots  352 . Slots  352  are arranged to align with apertures  252  in sheathing panels  250 . 
     Lower section  200  and upper section  300  are mated together by aligning vertical members  220  and mating members  320 . Upper section  300  is allowed to slide down until vertical members  220  are supporting ceiling plate  310 , giving safe haven wall  100  a height that is less than the ceiling of the mine. Safe haven wall  100  is then transported to the location of the safe haven and placed across the opening to the safe haven. Jacks are then uses to elevate upper section  300  until ceiling plate  310  is adjacent to the ceiling of the mine. Base plate  210  and ceiling plate are then bolted to the mine floor and mine ceiling respectively using anchor bolts. Vertical members  220  and mating members are then bolted together using bolts  258  that pass through slots  324  in mating members  320  and apertures  214  in vertical members  220  that are aligned. Overlap plates  350  are then bolted to sheathing panels  250  utilizing bolts  258  that pass through slots  352  in overlap plates  350  and apertures  252  in sheathing panels  250  that are aligned. To form an airtight seal, expanding foam or pressurized grout bags or other MSHA approved sealant or other suitable fill material or a combination thereof may be used to address any unevenness in the mine floor or mine ceiling at the installation location. Alternatively, safe haven wall  100  may be placed on top of unfilled pressurized grout bags and unfilled pressurized grout bags are placed on top of safe haven wall  100  and between sliding panels  400  and  410  and the vertical walls of mine. Once upper section  300  is elevated into position adjacent to the mine ceiling, the pressurized grout bags are filled to create a seal around the perimeter of safe haven wall  100 . Once the pressurized grout bags have cured sufficiently, safe haven wall  100  is anchored to the mine floor and mine ceiling. 
     Opposing ends of the wall  100  are provided with sliding panels  400  and  410  that can be adjusted to alter the length of the wall. Sliding panels  400  and  410  are preferably formed from steel. Sliding panel  400  is affixed to sheathing panel  250  at each end of wall  100  using bolts  258  that pass through apertures  406  in sheathing panel  250  and horizontal slots  402  in sliding panel  400 . Sliding panel  402  is affixed to overlap plate  350  at each end of wall  100  using bolts  258  that pass through apertures  416  in overlap plate  350  and horizontal slots  412  in sliding panel  410 . Sliding panel  410  may also be provided with rod  414  welded to a bottom portion of sliding panel  410  to reduce the gap between the inner surface of sliding panel  410  and the outer surface sliding panel  400 , making it easier to form an airtight seal using expanding foam. The end portions of sliding panels  400  and  410  that will be adjacent to the mine walls may be provided with angle tabs  418  that can be used to bolt sliding panels  400  and  410  to the adjacent mine wall. 
     If needed, safe haven wall  100  may be configured to permit ingress and egress to a safe haven defined by safe haven wall  100  while still being able to create a positive pressure environment within the safe haven. In the illustrated embodiment aperture  251  is defined in sheathing panel  250  to permit such ingress and egress and hatch  500  is provided to form an airtight seal when it is in a closed position. In the illustrated embodiment, hatch  500  comprises door  510 , gasket  520 , hinges  530 , and latching mechanism  540 . Door  510  is a full overlay door that is larger than aperture  251 . Gasket  520  is affixed to the inner facing surface of door  510  and forms a circle that is of a larger diameter than aperture  251 . When door  510  is in its closed position, gasket  520  is received by circular groove  253 , which is defined in the outer surface of sheathing panel  250  and surrounds aperture  251 , to form an airtight seal. Steel plate  511  (show in  FIGS. 11 and 12 ) may be used around all or a portion of the perimeter of door  510  to stiffen door  510  and prevent it from flexing when latched. 
     Hinges  530  are selected to enable door  510  to be parallel to sheathing panel  250   h  when door  510  is in its closed position without causing undue binding on the hinge side of door  510  and without causing door  510  to be distorted when latched in its closed position. In the illustrated embodiment, each hinge  530  further comprises hinge bolt  532  and hinge strap  536 . Hinge bolt  532  is adapted on a first end to be bolted to vertical member  220  and that terminates at the opposing end in a hinge pin that extends perpendicularly to hinge bolt  532 . Hinge strap  536  further comprises a loop for receiving the hinge pin and is adapted to be bolted to door  510 . 
     Hatch  500  is also provided with a latching mechanism to hold hatch  500  in its closed, airtight position. In the illustrated embodiment, latching mechanism  540  comprises rotatable shaft  542  that extends through vertical member  220 . Affixed to the end of rotatable shaft  542  on the exterior side of safe haven wall  100  is latching member  544 . Latching member  544  is position to engage the outer surface of door  510  when door  510  is in its closed position and to latch door  510  in its closed position. Affixed to the end of rotatable shaft  542  on the interior side of safe haven wall  100  is a handle that allows latching mechanism  540  to be rotated from the interior of the safe haven. Door  510  may also be provided with a handle (not shown) extending inward toward the safe haven to assist with holding door  510  in its closed positions as it is being latched. While the illustrated embodiment includes only a single latching mechanism  540 , more than one may be included as deemed necessary to sufficiently latch door  510  in its closed positions. Where multiple latching mechanisms  540  are utilized, latching mechanism  542  may be adapted to extend through base plate  210 , overlap plate  350 , and/or ceiling plate  310  in similar fashion. 
     To facilitate movement of safe haven wall  100  within the mine, safe haven wall  100  may be provided with legs  450 . Each leg  450  extends from the inward facing surface of one of vertical members  220 . Each leg  450  comprises post portion  452  that, in the illustrated embodiment, is formed from rectangular steel tubing, but any material of suitable strength may be used. Foot  454  is affixed to the end of post portion  452 . Foot  454  is preferably formed to facilitate sliding wall  100  through the mine to the location of the safe haven. In the illustrated embodiment, this is accomplished by forming foot  454  from a rectangular piece of steel plate having a width approximately equal to the width of post portion  452  and bending up the end portions of the steel plate that extend toward opposing ends of wall  100 . Alternatively, foot  454  can have width greater than the width of post portion  452  with all edges bent upward to form a cup shape to facilitate sliding the wall laterally into and out of the entrance to the safe haven as well and longitudinally through the mine. To further facilitate the transport of safe haven wall  100  though the mine, each end of safe haven wall  100  may be provided with hitch  460 . 
     Safe haven wall  100  may also be provided with a number of ports  110 . In the illustrated embodiment, ports  110  are formed from circular pipe and sealed with threaded caps. Ports  110  enable cables, water lines, air supply lines, and the like to be extended through safe haven wall  100  and into the safe haven. One or more ports  100  can also be fitted with a one-way purge valve that will allow the atmosphere of the safe haven to be purged utilizing a continuous supply of fresh air from an external device such as the HUBBLE® breathable air unit. When a port  100  is opened to allow the insertion of cables, water lines, air supply lines, and the like, an airtight seal capable of withstanding a static pressure of 15 PSI can be achieved using expanding foam. 
     While the height of safe haven wall  100  can adapted for mines with different ceiling heights, safe haven wall  100  can also be mounted on base  120  if the ceiling height exceeds its maximum height. Base  120  can be formed as a rigid beam with sufficient resilience to withstand the weight of safe haven wall  100 . While base  120  is illustrated as a solid block, base  120  may be constructed from other types of beam steel such as I beams, H beams, or box beams, tubing, or solid members such that the overall wall height is capable of withstanding as static pressure of 15 PSI. Base  120  must be secured to the mine floor in such a manner to allow it to withstand a static pressure of 15 PSI. One way this may be accomplished is by providing the inward side of base  120  with a plurality of angle brackets  122  that may be bolted to the floor of the mine. Safe haven wall  100  is bolted to the upper surface of base  120 . As discussed above, it may be necessary to use expanding foam or pressurized grout bags or other suitable fill material or a combination thereof to form an airtight seal if the floor of the mine is not level and smooth. An alternative design of base  120  is shown in  FIG. 9 . In this design, base  120  is formed from hollow structural steel (“HSS”) configured as rectangular hollow beam  130 . If the rectangular cross-section has a pair of sides that are longer, the longer sides are attached to safe haven wall  100  and to the mine floor. In this configuration, one of the pair of sides that will be upright when base  120  is installed may be provided with apertures  132  to facilitate the bolting of hollow beam  130  to the mine floor and to safe haven wall  100 . If additional height is required, an additional HSS beam  134  can be welded to the top of beam  130  as illustrated in  FIG. 10 . In this case, one of the pair of sides of both beam  130  and beam  134  that will be upright when base  120  is installed may be provided with apertures  132 . In either case, or in the case of a solid beam, steel plate  136  may be welded to the bottom of beam  130  to provide an alternate means of bolting beam  130  to the mine floor. Steel plate  136  may also be provided with lip  138  to give base  120  a “sled-like” capability to facilitate movement of base  120 . 
     To install safe haven wall  100 , the first step is to determine the approximate measurements of the opening to be sealed. This will enable selection or fabrication of safe haven wall  100  that is best suited for the particular mine. It is generally advantageous to assemble lower section  200  to upper section  300  outside of the mine. Ceiling plate  310  and base plate  210  are predrilled for attaching safe haven wall  100  to the ceiling and floor (or base  120 ) respectively. To facilitate installation, a template with the hole patterns of ceiling plate  310  and base plate  210  can be used to enable the predrilling of the ceiling or floor of the mine. If predrilling is not done, the anchor locations can be drilled as part of the anchoring process once safe haven wall  100  is in place. Safe haven wall  100  is then transported to the installation location using hitch  460 . Once safe haven wall  100  is at the installation location, it is tilted into place on the floor of the mine or base  120 . If base  120  is used, it is first set in place across the opening to be sealed and anchored to the floor of the mine. Upper section  300  is then raised to be adjacent to the ceiling of the mine and anchored to the ceiling of the mine. Bottom wall  200  is attached to the floor of the mine or base  120  (this can be done simultaneously with anchoring upper section  300  to the ceiling of the mine). Vertical members  220  and mating members are bolted together using bolts  258  that pass through slots  324  in mating members  320  and apertures  214  in vertical members  220  that are aligned. Sliding panels  400  and  410  are then slid outward and bolted in place to engage the vertical wall portions of the mine adjacent to the ends of safe haven wall  100 . When safe haven wall  100  is mounted on base  120 , if base  120  is not the full width of the opening, it can be provided with separate sliding panels or sliding panel  400  can be extended downward the height of base  120 . As the wall is installed and after installation, safe haven wall  100  can be sealed to the mine floor, ceiling, and sidewalls using pressurized grout bags, expanding foam, and similar known sealing materials that are approved for use in a mine. If grout bags are used, they can be put into place between the safe haven wall and the mine floor, wall, or ceiling and filled once the safe haven wall has been bolted in place. Once safe haven wall  100  is set in place, at least one fresh air line is installed through one of ports  110  and affixed to a regulator. At least one relief valve is installed in another of ports  110  to enable a positive pressure to be maintained within the safe haven defined by safe haven wall  100 . 
     Attached hereto as Appendix 1 and incorporated by reference herein is a report prepared for submission to MSHA that further describes the invention. Attached hereto to as Appendix 2 and incorporated by reference herein is an installation manual with further details of the process for installing the safe haven wall in a mine. 
     It should be noted that this describes only the particular, illustrated embodiment. Those of skill in the art will recognize that other choices could be made for the various components of safe haven wall  100  without departing from the scope of the invention. For example, vertical members  220  could be formed from steel tubing and mating members  320  from a smaller cross-section tubing that would telescope in an out of vertical members  220 . 
     The foregoing described embodiments are exemplary in nature and are not intended to limit the scope of the invention.