You are an expert at summarizing long articles. Proceed to summarize the following text:

You are an expert at summarizing long articles. Proceed to summarize the following text: 
RELATED APPLICATIONS 
     This application is a Nonprovisional patent application related to U.S. Provisional Patent Application Ser. No. 61/407,805 filed Oct. 28, 2010 entitled “MULTI-USER PORTABLE TOILET”, which is incorporated herein by reference in its entirety, and claims any and all benefits to which it is entitled therefrom. 
     FIELD OF THE INVENTION 
     The present invention relates to an improved multi-user portable toilet, and more particularly, to an outdoor portable toilet with external urinal, and arrangements thereof, to meet public needs more efficiently. 
     BACKGROUND OF THE INVENTION 
     Portable toilets are simple enclosures containing a chemical or holding tank-type toilet. They are typically used at construction sites, outdoor sporting events, fairs, markets, and other temporary or infrequent gatherings and events. Most portable toilets have the typical open-front-U-shaped toilet seat with cover with or without an optional internal urinal system. They are often constructed out of light weight molded plastic. 
     The present invention is part of the next generation of portable restrooms, designed to counter the problems that arise due to massive attendance at popular outdoor events such as concerts, fairs, and festivals. Large music festivals which generate traffic of up to 80,000 people per half day should provide up to 1,190 portable restroom units. This alone amounts to more than 26,000 square feet that the venue is required to set aside for the restroom area or areas. Often, events are unable to meet these quotas due to rental cost or space restraints, which result in long lines and rapidly degenerating hygienic conditions. Moreover, with long lines, impatience often leads to inappropriate behavior, such as users urinating on the nearby structure or landscaping. 
     Portable urinal units are brought in sometimes to meet overwhelming public demands at outdoor events. However, often these systems compromise the user&#39;s privacy. Also, almost all portable urinal units need their own waste tank, which increases difficulty in cleaning. 
     U.S. Publication No. 20090235445, published Sep. 24, 2009 to Goldstein teaches an addition of an external urinal to a conventional portable toilet. It however fails to address the issue of privacy. Additional portable screens may be introduced to alleviate the associated problems, but add to installation and break down time and costs. 
     Advantages and Summary of Invention 
     Through innovative use and placement of an external urinal, the present invention allows two people to use a single unit simultaneously, while maintaining privacy of both users. The present invention is a portable toilet assembly with an internal chamber, an external urinal and a shared waste container located beneath the internal chamber. 
     The simultaneous use of the present invention by 2 users drastically reduces wait times by redirecting urinal users to the back side areas of the units, an area which is generally un-used on the standard portable toilet. The present invention also has the ability to accommodate more users with fewer units which not only reduces the amount of space needed for restrooms at outdoor events or other events in which sufficient indoor restroom facilities are lacking, but also reduces costs, thus allowing extra budget allowance to be spent elsewhere. With less units required per event, less are manufactured and transported, greatly reducing the carbon footprint of portable restrooms. The present invention&#39;s external curvature design, integrated into both its overall form and into its structural support are reminiscent of water and gentle waves when multiple units are place side by side. 
     The portable toilets of the present invention can be arranged in rows, circular and other configurations to best suit the spatial and/or aesthetic requirements and considerations of the venue. Due to the unique design of the present invention, a singular unit in itself can provide acceptable privacy to users of the external urinal. When multiple units are arranged strategically, they create not only a natural private space for the external urinal users, but each adjacent unit provides additional privacy for all users. 
     Further details, objects and advantages of the present invention will become apparent through the following descriptions, and will be included and incorporated herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1A through 1D  are representative isometric views of an embodiment of the multi-user portable toilet  100  of the present invention. 
         FIGS. 2A through 2D  are representative side views of an embodiment of the multi-user portable toilet  100  of the present invention.  FIG. 2E  is a representative top view of an embodiment of the multi-user portable toilet  100  of the present invention. 
         FIG. 3A  is a representative cross-sectional view of an embodiment of the multi-user portable toilet  100  of the present invention showing the privacy compartment  150 . 
         FIG. 3B  is a representative isometric view of an embodiment of the multi-user portable toilet  100  of the present invention showing assembly of external urinal panel  108 . 
         FIG. 3C  is a representative top isometric view of an embodiment of the multi-user portable toilet  100  of the present invention showing the contour design of top panel  136 . 
         FIG. 4  is a representative lateral, cut-away schematic view showing an embodiment of the portable toilet  100  of the present invention showing the internal commode, waste containment chamber, external urinal, drainage means connecting the external urinal to said waste containment chamber and acoustic insulation/sound-proofing disposed along the compartment shell to provide additional privacy for multiple simultaneous users. 
         FIG. 5  is a representative isometric view of an alternative embodiment of multi-user portable toilet  600 . 
         FIG. 6A  is a representative top side view of multiple multi-user portable toilets  100  of the present invention in a row arrangement  200 . 
         FIG. 6B  is a representative back side view of multiple multi-user portable toilets  100  of the present invention in a row arrangement  200 . 
         FIG. 6C  is a representative upper back side view of multiple multi-user portable toilets  100  of the present invention in a row arrangement  200 . 
         FIGS. 7A through 7C  are representative side top isometric and top views, respectively, of multiple multi-user portable toilets  100  of the present invention in a stall arrangement  300 . 
         FIGS. 8A and 8B  are the representative top and upper isometric views, respectively, of multiple multi-user portable toilets  100  of the present invention in a chamber arrangement  400 . 
         FIGS. 9A and 9B  are the representative top and upper isometric views, respectively, of multiple multi-user portable toilets  100  of the present invention in a ring arrangement  500 . 
     
    
    
     For a better understanding of the invention reference is made to the following detailed description of the preferred embodiments thereof which should be taken in conjunction with the prior described drawings. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The description that follows is presented to enable one skilled in the art to make and use the present invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be apparent to those skilled in the art, and the general principals discussed below may be applied to other embodiments and applications without departing from the scope and spirit of the invention. Therefore, the invention is not intended to be limited to the embodiments disclosed, but the invention is to be given the largest possible scope which is consistent with the principals and features described herein. 
       FIGS. 1A through 1D  are representative isometric views of an embodiment of the multi-user portable toilet  100  of the present invention. In one embodiment, multi-user portable toilet  100  of the present invention is a simple portable enclosure consisting essentially of an internal toilet chamber, i.e., privacy chamber  150 , as best shown in  FIG. 3A , an external receptacle/urinal  106  and a shared waste containment chamber  102  disposed within the privacy chamber  150 . In one embodiment, essential portions of multi-user portable toilet  100  are often constructed out of light weight molded plastic, for easy transportation and cost effectiveness. As best shown in  FIGS. 1A to 1D , instead of having four side panels to create a rectangular internal chamber, the multi-user portable toilet of the present invention  100  has five side panels, viz., door panel  130  at the front, right panel  132  and left panel  134 , both adjacent to door panel  130 , back panel  138 , and urinal panel  108  that connects right panel  132 , or left panel  134 , to back panel  138 . All five side panels leave a footprint, and connect to the top panel  136 , in the shape of a pentagon. 
       FIGS. 2A through 2D  are representative side views of an embodiment of the multi-user portable toilet  100  of the present invention.  FIG. 2E  is a representative top view of an embodiment of the multi-user portable toilet  100  of the present invention. As best shown in  FIGS. 1B and 2E , the top panel  136  is a pentagon resembling a rectangle with one of its corners cut away, that corner replaced with urinal panel  108 . As best shown in  FIGS. 1C and 2A , a door  135  is installed on door panel  130  so users can enter and exit multi-user portable toilet  100 . In one embodiment, a lock or other mechanical closures [not shown] can be installed on door  135  to enhance privacy. A slanting or sloped roof line  202  assists in preventing water pooling on the upper panel  136  during rain, etc. 
       FIG. 3A  is a representative vertical cross-sectional view of an embodiment of the multi-user portable toilet  100  of the present invention showing the privacy compartment  150 . In one embodiment, five side panels, viz.; door panel  130  at the front, right panel  132  and left panel  134 , back panel  138 , and urinal panel  108 ; and top panel  136 , and optionally floor panel  101 , create an enclosure i.e. privacy compartment  150 . As best shown in  FIG. 3A , privacy compartment  150  is an enclosed space which further equipped therein a commode or toilet  104  emptying into a waste containment chamber  102 . In one alternative embodiment, water basin which also emptying into waste containment chamber  102 , a cold/hot water tap, a soap dispenser could be included within privacy compartment  150 . In another embodiment, commode with flushing and plumbing can be introduced to make the present invention  100  more pleasant. In yet another embodiment, lighting fixtures  140  can be installed within privacy compartment  150  for evening events. In yet another embodiment, electric fan, air-conditioning unit  133  and music loudspeakers [not shown] can be installed to further enhance the present invention  100 . In one embodiment, speakers [not shown] can also be useful for providing audio instructions for use of the toilet  100 , radio performance, emergency news broadcast, etc. optional equipment for the portable toilet  100  include auxiliary plumbing service hookups, hot water service, hot water heater, internal steam or chemical cleaning, holding tank for water, hot water and/or chemical cleaners. 
       FIG. 3B  is a representative isometric view of an embodiment of the multi-user portable toilet  100  of the present invention showing assembly of external urinal panel  108 . In one embodiment, the external urinal panel  108  further has an urinal  106  installed. The urinal  106  is also equipped with drainage means  114  such that it empties into the shared waste containment chamber  102  within privacy compartment  150  through drainage hole  112 . In one embodiment, urinal panel  108  may be recessed, i.e., disposed within a cut-out or alcove in the external wall  109  surrounding the chamber to afford privacy to users. Further, the external wall  109  separating urinal panel  108  from privacy compartment  150  may include sound barrier or sound proofing layer  110  for further privacy between two simultaneous users of toilet  104 , i.e., one within privacy compartment  150  and one using external urinal  106 . it will be understood that sound proofing layers can also be installed, clad or lined on right panel  132 , left panel  134  and/or back panel  138  to provide further privacy to users. In one embodiment, sound proofing layers increase acoustic separation between the inside and outside of privacy compartment  150 . Examples of construction material of sound proofing layers or other sound reducing means  110  include QUIET BARRIERS-brand multi-layer soundproofing composite material. This material is an engineered acoustical composite of ½ inch decoupling foam, ⅛ inch high-mass sound-blocking barrier, and ¾ inch noise absorbing foam with 3 mm reinforced mylar facing, as well as other active and passive noise disturbance and cancelling technologies, designed to provide significant air and structure borne noise reduction in a low-profile configuration. 
       FIG. 3C  is a representative top isometric view of an embodiment of the multi-user portable toilet  100  of the present invention showing the contour design of top panel  136 . In one embodiment, top panel  136  has vents  133  which are openings that improve air ventilation of privacy compartment  150 . In one alternative embodiment, an electric fan [not shown] can be installed around vents  133  to further enhance ventilation. Moreover, one function of top edge panel  120  is to divert falling rain away from door panel  130  and urinal panel  108 . External gutters can also be located to divert rain or other water fall to one side or another or to any intermediate, drainage point from the roof and top panel  136  as desired. Downspouts or scuppers can also be installed on the sides or corners of the portable toilet  100  of the present invention to collect and divert rain as desired. Directed drainage is also achieved by the contoured surface of top panel  136  which may have one or more ridges  122  to drain or divert moisture to right panel  132 , left panel  134  and/or back panel  138 . It is important to divert rain water away from the user. As for the urinal panel  108 , since it has urinal  106  that empties into waste containment chamber  102 , it is imperative to divert as much rain water away from urinal panel  108  as possible to avoid overflowing waste containment chamber  102 . In one embodiment, gutter or railing  120  can be installed at edge of top panel  136  at top of urinal panel  108 , acting as a dam to rain water. 
       FIG. 4  is a representative lateral, cut-away schematic view showing an embodiment of the portable toilet  100  of the present invention. In this embodiment, two users can multi-user portable toilet  100  simultaneously. The drainage means  114  connecting urinal  106  to waste containment chamber  102  within privacy compartment  150  and sound proofing layers  110  disposed along the side panels to provide additional privacy for simultaneous users. 
       FIG. 5  is a representative isometric view of an alternative embodiment of multi-user portable toilet  250  of the present invention where two external urinals  106  and  107  [not shown] are disposed upon the external shell, separated by a privacy protrusion  502 . In one alternative embodiments, urinals  106  are installed on both the urinal panel  108  and back panel  138  such that three users can use multi-user portable toilet  600  simultaneously. 
       FIG. 6A  is a representative top side view of multiple multi-user portable toilets  100  of the present invention in a row arrangement  200 .  FIG. 6B  is a representative back side view of multiple multi-user portable toilets  100  of the present invention in a row arrangement  200 .  FIG. 6C  is a representative upper back side view of multiple multi-user portable toilets  100  of the present invention in a row arrangement  200 .  FIG. 6D  is a representative upper, isometric view showing a method of use of multiple multi-user portable toilets  100  of the present invention in a row arrangement  200 . In outdoor events, it is common to arrange multiple portable toilets together to create a temporary lavatory area. When a number of multi-user portable toilets  100  of the present invention are arranged in a row arrangement  200  as best shown in  FIGS. 6A to 6D , left panel  134  of each multi-user portable toilet  100  acts as a screen, creating an external urinal area  210  within each multi-user portable toilet  100 . The external urinal area  210  provide even more privacy to urinal users. 
       FIGS. 7A through 7C  are representative side, top isometric and top views, respectively, of multiple multi-user portable toilets  100  of the present invention in a stall arrangement  300 . In events held in places where outside walls  310  are available, multiple multi-user portable toilets  100  can be arranged in stall arrangement  300  as best shown in  FIGS. 7A to 7C , creating a temporary stall  330  for the users of the external urinals  106 . 
       FIGS. 8A and 8B  are representative top and upper isometric views, respectively, of multiple multi-user portable toilets  100  of the present invention in a chamber arrangement  400 . Multiple multi-user portable toilets  100  can be installed, as best shown in  FIG. 8A , to block on end of an event venue that has barricades  410  to create an instant outdoor lavatory  440  for urinal users. 
       FIGS. 9A and 9B  are representative top and upper isometric views, respectively, of multiple multi-user portable toilets  100  of the present invention in a ring arrangement  500 . At event venues that no walls or barricades are available, multiple multi-user portable toilets  100  of the present invention can be installed in a ring arrangement  500 . Instantaneously creating a larger area for users to use urinals  106 . 
     For a better understanding of the invention reference is made to the following detailed description of the preferred embodiments thereof which should be taken in conjunction with the prior described drawings. 
     Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Although any methods and materials similar or equivalent to those described can be used in the practice or testing of the present invention, the preferred methods and materials are now described. All publications and patent documents referenced in the present invention are incorporated herein by reference. 
     While the principles of the invention have been made clear in illustrative embodiments, there will be immediately obvious to those skilled in the art many modifications of structure, arrangement, proportions, the elements, materials, and components used in the practice of the invention, and otherwise, which are particularly adapted to specific environments and operative requirements without departing from those principles. The appended claims are intended to cover and embrace any and all such modifications, with the limits only of the true purview, spirit and scope of the invention.

Summary:
An improved portable toilet for simultaneous, private use by two persons, the portable toilet which contains an internal compartment having a commode, a waste containment chamber disposed below the commode for receiving waste, an external shell enclosing the compartment and the waste containment chamber, at least one urinal disposed externally upon the external shell and drainage system connecting the external urinal to the waste containment chamber. The portable toilet of the present invention has a cross-section and footprint in the shape of a pentagon.