Abstract:
A water tank fitted with a fall arrest assembly, a rescue device, and a rescue kit. The fall arrest assembly provides a safe means for personnel to perform inspection and maintenance activities on top of a water tank. The rescue device and rescue kit provide a safe and expeditious means to perform rescue activities in case of an emergency either inside or on top of a water tank. The water tank thus takes into consideration the safety of both the patient and the rescuers with the use of the fall arrest assembly and rescue device and rescue kit.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of the filing date of U.S. Provisional Patent Application Ser. No. 62/084,044, filed 25 Nov. 2014, for “Water Tank Fall and Arrest System,” the disclosure of which is hereby incorporated herein in its entirety by this reference. 
     
    
     BACKGROUND 
       [0002]    This disclosure relates to a transportable water tank having a fall arrest and rescue apparatus incorporated into the top of the water tank. In particular, the disclosure includes the use of a fall arrest cable tie-off assembly, a rescue kit, and a davit arm device that are all self-contained by the water tank for ease of accessibility. 
         [0003]    Keeping mobile equipment operational is a major concern for many industries. For example, in the mining industry, the general construction industry, and the highway construction industry, the operational availability of this equipment is crucial to the success of the business. One piece of equipment often used in these industries is a water tanker. The water tanker is used to spray water onto the surface soil to control dust and prevent dust from drifting to surrounding areas. 
         [0004]    The safety of the personnel responsible for maximizing the operational availability of the water tanker is important. At times, personnel may access the top of a water tank, for example, to access various components, such as water cannons, spray valves and lights, or to conduct an inspection of the tank and its components. Some of these components may be close to the edge of the top of the tank. The top of a water tank mounted to a truck chassis may be 15 feet to 30 feet above ground level, depending on the size of the vehicle and the tank capacity. Falls from these heights could cause serious bodily injury or even death. 
         [0005]    Another aspect of the inspection and maintenance activities that must be taken into consideration is how to rescue personnel should an emergency occur while people are inside of, or on top of, the water tank. Rescue plans describing how to extract a person from the top or from the inside of a tank in the event of an emergency may exist, but these plans may neglect to identify a safe and expeditious means of getting an injured person from the top of the tank to the ground and into the care of advanced medical personnel. 
       SUMMARY 
       [0006]    The present disclosure provides a water tank safety system that overcomes many of the shortcomings of prior designs. The present system includes various features. For example, personnel may attach the lanyard of their safety harness to a fall arrest tie-off assembly. The fall arrest tie-off assembly allows personnel to access all areas on top of the tank and is designed to prevent a fall beyond the length of the harness lanyard. 
         [0007]    The safety system may also include a rescue kit secured to the top of the water tank for easy access by rescue personnel in an emergency. The rescue kit contains various items required to conduct a proper rescue. These items are used to rescue a person from the interior of the tank and to lower the patient from the top of the tank to the ground. The items include, but are not limited to, a self-braking descender, steel carabiners, a rope grab, a short haul pulley, anchor straps, and rope. The items are typically stored in a water-proof storage bag. 
         [0008]    The water tank safety system may include a rescue device comprised of a davit arm, a davit arm base and fall arrest tie-offs. The davit arm is stored on top of the tank near the rescue kit. The davit arm is inserted into a davit arm base that is mounted to a davit arm mount bracket. The mount bracket is permanently attached to the top of the water tank. The davit arm utilizes various components in the rescue kit and is used to lower a patient from the top of the water tank to the ground. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    Other features and advantages of the present disclosure will be apparent from reference to the following Detailed Description taken in conjunction with the accompanying Drawings, in which: 
           [0010]      FIG. 1  depicts a side elevation view of a water tank on a vehicle chassis; 
           [0011]      FIG. 2  depicts a front isometric view of a water tank with the safety system installed thereon; 
           [0012]      FIG. 3  depicts an isometric view of a shuttle sliding over cable and system anchor components of the fall arrest assembly; 
           [0013]      FIG. 4  depicts a cross-sectional view of the shuttle sliding over the cable and system anchor components of the fall arrest assembly; 
           [0014]      FIGS. 5A, 5B, and 5C  depict perspective views of elements of the cable and anchor components of  FIG. 2 ; and 
           [0015]      FIG. 6  depicts a perspective view of a rescue device. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]      FIG. 1  depicts a representative vehicle  10  for carrying a water tank  12 . The configuration shown is typical of a water tanker truck used in the mining industry for dust suppression and fire control. However, the water tank  12  may be attached to other types of vehicles  10  such as on-highway vehicles, trailers, or the like. Those skilled in the art will appreciate that the tank  12  may be constructed with various physical dimensions to accommodate the various sized vehicles  10  on which the tank  12  may be mounted. 
         [0017]      FIG. 2  depicts a representative water tank  12  on which a fall arrest assembly  20 , a rescue device  30  and a rescue kit  40  are installed according to the present disclosure. The configuration shown is typical of a water tank  12  used in the mining industry for dust suppression and fire control. The water tank  12  includes a top  14  on which the fall arrest assembly  20 , rescue device  30  and rescue kit  40  are attached, as well as a ladder  16  that provides access from the vehicle  10  deck to the top  14  of the water tank  12 . In some embodiments, the top  14  of the water tank  12  may also be accessed from the vehicle  10  deck by other devices such as a stairway. Those skilled in the art will appreciate that the fall arrest assembly  20  and rescue device  30  of the present disclosure may be constructed with various physical dimensions and configurations to accommodate the various sized water tanks  12 , or other devices on which the fall arrest assembly  20 , rescue device  30 , and rescue kit  40  may be installed. 
         [0018]    Typically, the fall arrest assembly  20  is installed on the top  14  of the water tank  12  during manufacturing of the water tank  12 . However, the fall arrest assembly  20 , the rescue device  30  and the rescue kit  40  need not be installed during the manufacture of the water tank  12  but may also be retro-fitted to an existing water tank  12 . The fall arrest assembly  20  includes several anchors  22  mounted on mounting blocks  23 , a plurality of which are affixed around the top  14  of the water tank  12 . A safety cable  24  is routed through a loop or eyelet formed in the top of each of the anchors  22  and the cable  24  is put into tension, typically the tension suggested by the manufacturer, as will be understood by one of skill in the art. The fall arrest assembly  20  may fashioned from elements offered in the industry; the embodiment depicted relies heavily on the Skyline Horizontal Anchor Device offered by Skylotec GmbH of Neuwied, Germany. 
         [0019]      FIG. 5A  depicts two anchors  22 , one curving in one direction and the other in the opposite direction. This opposite curvature permits the cable  24  to be curved around the top  14  of the water tank  12 . As a result, the entire upper surface  14  of the water tank  12  may be visited by a worker without removing the worker&#39;s lanyard  52  from the shuttle  26 . 
         [0020]      FIG. 5B  depicts a termination anchor  42  on a mounting block  23 . In the embodiment depicted in  FIG. 5B , a compensator  44  affixed to the termination anchor  42  includes an integrated eye bolt to which a first end of the cable  24  is attached. The compensator  44  provides a certain degree of shock absorption to compensate for tension in the cable  24 . If the compensator  44  undergoes tension beyond a certain point (typically set by the manufacturer during manufacture of the compensator), the eye bolt over-extends, providing visual evidence to notify users that the cable  24  has been stretched too far, and the compensator  44  needs to be replaced. 
         [0021]      FIG. 5C  depicts another termination anchor  42  on a mounting block  23 . In the embodiment depicted in  FIG. 5C , the second end of the cable  24  is attached to a wire rope thimble  52 . The thimble  52  connects to a turnbuckle  54  which in turn connects to a tension indicator  56 . The turnbuckle  54  may be used to increase or decrease the tension in the cable  24 , as indicated by the tension indicator  56 . 
         [0022]    Prior to accessing the top  14  of the water tank  12 , personnel put on an OSHA, ANSI, CSA, or other approved safety harness  50 . A shuttle  26  (see  FIGS. 3 and 4 ) is attached to the safety cable  24  of the fall arrest assembly  20 . When personnel access the top  14  of the water tank  12 , the personnel attach a lanyard  52  from the safety harness  50  to the shuttle  26 . Personnel may then access the entire top  14  of the water tank  12  to perform inspection or maintenance tasks while attached to the fall arrest assembly  20 . 
         [0023]    In the embodiment depicted in  FIG. 2 , personnel may also access an entry point  60  into the water tank  12  while being attached to the fall arrest assembly  20 . Once at the entry point  60  on the top  14  of the water tank  12 , personnel may detach the lanyard  52  from the shuttle  26  and access the interior of the water tank  12  to perform inspection, maintenance and cleaning functions. All personnel must follow approved entry procedures specific to the location prior to entering the water tank  12 . The approved entry procedure will vary from site to site based on the governing safety regulations. Although  FIG. 2  depicts an entry point  60  for the Westech Stairway Access Tank (this tank is the subject of U.S. patent application Ser. No. 14/345,726 filed Mar. 19, 2014, the disclosure of which is incorporated herein in its entirety by this reference), different embodiments of the water tank  12  may have other entry point  60  configurations. 
         [0024]      FIG. 3  depicts one embodiment of a shuttle  26  and illustrates how the shuttle  26 , when attached to the cable  24  of the fall arrest assembly  20 , slides along the cable  24  and the anchors  22 . The cable  24  is routed through each of the anchors  22  of the fall arrest assembly  20 . The inside diameter of the shuttle  26  is large enough so as to be able to slide over the anchors  22  through which the cable  24  is routed. Typically, the shuttle  26  has a locking mechanism that secures the shuttle  26  around the cable  24  and prevents the shuttle  26  from accidentally detaching from the cable  24 . 
         [0025]      FIG. 4  is a cross-sectional view of one of the anchors  22  and the shuttle  26  depicted in  FIG. 3 .  FIG. 4  depicts how the cable  24  is routed through the anchors  22 .  FIG. 4  also depicts the clearance between the shuttle  26  and both the cable  24  and the anchor  22  that allows the shuttle  26  to freely slide around on the fall arrest assembly  20 . It will appreciated by those skilled in the art that the shuttle  26  and anchors  22  may have different configurations in different embodiments, all of which would meet the functionality requirements of the fall arrest assembly  20 . 
         [0026]    During the manufacture of the water tank  12 , a rescue device  30 , as depicted by the embodiment shown in  FIG. 2 , may be installed on the top  14  of the water tank  12 . As depicted in perhaps more detail in  FIG. 6 , the rescue device  30  includes a davit arm mount bracket  32  permanently attached to the top  14  of the water tank  10 . A davit arm base  33  mounts to the mount bracket  32 . Fall arrest tie-offs  34  are also permanently attached to the top  14  of the water tank  12 . A davit arm  36  is stored on top  14  of the water tank  12  for ease of access in the case of an emergency that would require a person to be lowered off the top  14  of the water tank  12  to the ground. As depicted in  FIG. 2 , the davit arm  36  is mounted on the davit arm base  33  when in use. 
         [0027]    A rescue kit  40  may be stored on top  14  of the water tank  12  for ease of access in case of an emergency. The rescue kit  40  contains various pieces of equipment necessary or useful to perform a rescue from the water tank  12 . The equipment includes, but is not limited to, a self-braking descender, steel carabiners, a rope grab, a short haul pulley, anchor straps, and rope. The required equipment in each rescue kit  40  may be determined by the rescue team personnel responsible for conducting rescue activities. 
         [0028]    In the event of an emergency where an individual is injured in the interior of the water tank  12 , rescue personnel will utilize the fall arrest assembly  20 , the rescue device  30  and the equipment in the rescue kit  40  to perform a rescue. In a typical rescue scenario, a four person rescue team would arrive at the scene, assess the situation and suit-up with the necessary personal protection equipment (“PPE”). The PPE would typically include, but not be limited to, a safety harness  50  with lanyard  52 , safety glasses, hard hat, gloves, safety boots and air respirators as required. Two members of the rescue team are typically designated as the entry team and the other two members are typically designated as the exterior team. 
         [0029]    In the embodiment depicted in  FIG. 2 , the rescue team members would use the ladder  16  (or other alternative means, such as a staircase or a hydraulic man-lift) to access the top  14  of the water tank  12 . The entry team members would gather required equipment out of the rescue kit  40  to conduct the rescue from the interior of the water tank  12 . While the entry team performed the required actions to get the survivor to the top  14  of the water tank  12 , the exterior team members would attach their lanyards  52  to the fall arrest tie-offs  34  to ensure their safety during the rescue process. The exterior team would place the davit arm  36  into the davit arm base  32 . The davit arm  36  would then be rigged with the proper equipment, such as rope, carabiners and a self-braking descender from the rescue kit  40 . 
         [0030]    Once the entry team got the survivor to the top  14  of the water tank  12 , the entry team members would also attach their lanyards  52  to shuttles  26  on the fall arrest assembly  20  or the fall arrest tie-offs  34  to ensure their safety during the rescue process. If the survivor was wearing a safety harness  50 , then the survivor&#39;s safety harness  50  would be directly attached to the davit arm  36  of the rescue device  30 . The survivor would be raised off the top  12  of the water tank  12  and the davit arm  36  would be rotated out over the side of the water tank  12 . Once clear of the side of the water tank  12 , the survivor would be lowered to the ground and into the care of advanced medical personnel. It will be appreciated that other rescue equipment, such as a rescue basket, could be used with the rescue device  30  to lower the survivor from the top  14  of the water tank  12  to the ground depending on the situation. 
         [0031]    Although particular embodiments of the present invention have been described, those of skill in the art will appreciate that various modifications and changes may be made by those skilled in the art without departing from the spirit and scope of the invention. The present invention may be embodied in other specific forms without departing from its structures, methods, or other essential characteristics as broadly described herein and claimed hereinafter. The described embodiments are to be considered in all respects only as illustrative, and not restrictive.