1.  Field of the Invention
The present invention relates to cases for tablet computers.  More particularly, the present invention relates to cases for tablet computers in which the tablet computer is entirely sealed in an incut environment within the case.  The present invention also relates to audit tools that employ tablet computers. 
2.  Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98
The use of handheld computers in hazardous areas may lead to an increased risk of fire or explosion triggered by the presence of electricity in the handheld computer.  The handheld computer could serve as an ignition source in an area containing flammable fluids or vapors.  As such, handheld computers are restricted from use in such hazardous areas.  Any electrical devices used in such hazardous areas are often required to be certified according to the requirements specified in that particular field. 
Hazardous environments are classified into three classes.  Each of these classes focuses on the different types of hazardous materials that are in the immediate area.  As such, the handheld computers, or tablet computers, must be able to satisfy certain of these classification groups.  In particular, Class 1 areas will include flammable gases or vapors that are present in the air in sufficient quantities to produce an explosion in the event of an ignition source.  Class 2 areas are related to the presence of combustible dust.  Class 3 areas include ignitable fibers or materials that are too heavy to be suspended in air in sufficient quantities to produce an ignition. 
Each of these classes is divided into separate divisions that are based upon the likelihood that hazardous materials will be present.  Division 1 includes hazardous environments where pertinent hazardous material, such as vapor, dust and fibers, is present during normal conditions.  Division 2 relates to hazardous environments in which the flammable material will be present only in unusual or a fault conditions. 
With respect to handheld computers, such as tablet computers, it is important to be able to satisfy the Class 1 Division 1 standards.  If the handheld computer satisfies these requirements, then it would be UL-certified as “intrinsically safe”.  So as to satisfy the Class 1 hazardous environment classification, the tablet computer must have an explosion-proof enclosure or assembly which prevents any shorts, sparks, or other events from escaping outside of the enclosures.  With respect to flammable vapors, the handheld computer must have a case that effectively prevents entry of flammable materials into the enclosure.  Relative to Class 2 areas, the tablet computer must have a dust-ignition proof enclosure which prevents ignitable materials from entering the enclosure.  If the ignitable materials would enter the enclosure, they could be subject to the ignition arcs, sparks or heat within the enclosure.  As such, the enclosure should be entirely sealed around the tablet computer and the case should block any penetrations. 
In order to be an effective tool for use in Class 1 Division 1 environments, the tablet computer should be provided within a case that avoids any possible creation of arcs or sparks on the exterior of the enclosure while, at the same time, avoiding any openings or penetrations whereby flammable gases or dusts could enter the interior of the enclosure. 
A major problem associated with the use of tablet computers having an entirely sealed carrying case is the fact that the will build up in the interior of the case.  When heat builds up in the interior of the case, there is a need to be able to properly vent this heat to the ambient environment.  However, entirely sealed cases lack the ability to vent.  As such, a need has developed so as to provide a case for a tablet computer which avoids any penetrations while, at the same time, allowing for heat dissipation and release. 
Also, in the past, tablet computers have not been available for Class 1 Division 1 use since the tablet computers have various connections.  These connections can be in the nature of USB ports, sockets, and other elements.  Whenever sockets are used, there is a penetration which would allow for gases and dust to enter the interior of the tablet computer.  When USB ports are utilized, there is a possibility of a spark or arc occurring whenever an electrical connection is made.  As such, there is a need to develop a case for tablet computer which avoids the use of the USB ports and sockets. 
While assemblies or enclosures have been developed for use in such Class 1 Division 1 areas, these components are often expensive and not configured for use with particular electrical devices, such as tablet computers.  Also, these components may only satisfy the requirements for a particular class and division and would not be suitable for use in the other hazardous environments, such as Division 2 conditions.  Thus, there is a need for any intrinsically safe or explosion-proof case for a tablet computer that is capable of being safely used in varying types of conditions and hazardous environments. 
During the use of cases for tablet computers, it is important that no hazardous fumes or molecule penetrate the walls of the case such that an ignition can occur.  In the past, cases for tablet computers have been configured such that hazardous fumes and molecules could penetrate the walls of the case such that an ignition could occur.  This is particularly important where the tablet computers being used in a very explosive environment.  As such, need has developed so as to be able to provide a tablet computer whereby the interior of the tablet-computer case is completely isolated from the hazardous fumes or molecules. 
Whenever a tablet computer is normally utilized, there is a possibility of damage to the tablet computer.  This can occur by encountering water or by being dropped on a surface.  The dropping of the tablet computer on a surface can crack the glass of the tablet computer and damage the body of the computer.  The if the tablet computer should be dropped in water, then water can ingress through the openings in the tablet computer so as to damage the internal components.  As such, a need has developed so as to provide a case for a tablet computer that avoids damage to the tablet computer. 
In the past, cases that have been provided for tablet computers.  These cases have been formed of a polymeric material.  Unfortunately, these cases have often sharp corners that can be easily cracked or damaged if the tablet computer is dropped.  In other circumstances, the plastic material will encounter a sharp object when it is dropped and also tend to crack.  Whenever cracks occur, the case of the tablet computer would not be considered to be “intrinsically safe”.  As such, a need has developed so as to avoid any possible damage to the tablet computer caused by dropping onto a hard surface or into water. 
In the past, various patents and patent publications have issued relating to cases for tablet computers.  For example, U.S. Pat.  No.  5,583,742, issued on Dec. 10, 1996 to Noda et al.,  describes a computer with a protective cover having outwardly projecting cushioning portions.  In particular, this device employs a body case that houses a display.  An outer member is formed of an impact-resistant material integrally formed on the outside surface of the body case.  An outwardly-projecting cushioning portion is formed at each corner of the outside member.  Each of the cushioning portions has a first protective portion extending outwardly from the body case and a second protective portion projecting curvilinearly with respect to the first protective portion and extending onto a surface or a back of the body case.  Vent holes are formed in the body case which are sealed with a porous film.  The vent holes provided an escape path for gas produced by the battery in the event that the battery explodes within the body case. 
U.S. Pat.  No.  8,503,170, issued on Aug. 6, 2013 to Shu et al.,  shows a waterproof and shockproof cover for a pad computer.  The cover includes an upper housing, a base housing, a glass, a first rubber ring, a second rubber ring and four shockproof elements.  The base housing corresponds to the upper housing.  The upper housing comprises a first connection and the base comprises a second connection corresponding to the first connection so as to allow for the fastening of the base housing to the upper housing.  The upper housing includes a viewing window hole and a first groove formed around the rim of the viewing hole.  A first rubber ring is disposed within the first groove.  The glass covers the viewing window hole and the first rubber ring.  The four shockproof elements are disposed respectively at the four corners of a rectangular accommodation space of the base housing so as to bear the computer therein. 
U.S. Patent Publication No.  2012/0314354, published on Dec. 13, 2012 to G. Rayner, describes a housing for encasing a tablet computer.  The apparatus includes a housing that is configured such that the device may be fitted within the housing so as to be protected from shocks and liquid.  The housing includes top and bottom members that may be removably coupled together so as to form the housing.  Each top and bottom member includes a perimeter portion defined by proximal and distal ends and opposing sides.  The top and bottom members include respective clasping mechanisms that extend along the perimeter of the top and bottom members that are configured for engaging a third clasping mechanism, such as a locking comb or wedge feature.  The clasping mechanisms are configured for coupling the top and bottom members with one another so as to seal the housing. 
U.S. Patent Publication No.  2013/0193149 describes an enclosure for a tablet computer that includes a first portion and a second portion.  The first portion and the second portion are configured to be releasably coupled to each other.  The enclosure has an assembled configuration having an internal chamber.  The enclosure is configured to house the tablet computer within the internal chamber. 
It is an object of the present invention to provide a case for a tablet computer that satisfies Class 1 Division 1 requirements. 
It is another object of the present invention to provide a case for a tablet computer that has no ingress areas or penetrations whereby flammable or hazardous material can enter the interior of the case. 
It is another object of the present invention to provide a case for a tablet computer that allows for heat dissipation without the need for fans or penetrations into the case. 
It is another object of the present invention to provide a case for a tablet computer that can maintain a positive pressure within the interior of the case so as to prevent liquids and other gases from entering the interior of the case. 
It is another object of the present invention to provide a case for a tablet computer that includes intrinsically safe pin connections for the tablet computer. 
It is another object of the present invention to provide a case for a tablet computer that is easily readable. 
It is a further object of the present invention to provide an apparatus which is intrinsically safe, explosion-proof, and liquid-tight. 
It is still a further object of the present invention to provide an apparatus that effectively avoids cracking and damage to the case or the tablet computer in the event of dropping or other damaging contact. 
It is still a further object of the present invention to provide an apparatus that facilitates the ability to carry out audits in hazardous environments. 
It is still further object of the present invention to provide an apparatus which facilitates the ability to download data from the tablet computer. 
These and other objects and advantages of the present invention will become apparent from a reading of the attached specification and appinded claims.