Patent Publication Number: US-2018037307-A1

Title: Ultra-high pressure regulator and a method of using the same

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority under 35 U.S.C. §119 to U.S. Provisional Patent Application Nos. 62/280,916, which was filed Jan. 20, 2016, and 62/281,843 which was filed Jan. 22, 2016, both entitled “Ultra-High Pressure Regulator Device and Method of Use,” and each of which is incorporated in its entirety herein by this reference. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     The invention was made with Government support under Contract No. N00024-15-C-4024 awarded by the United States Navy. The Government has certain rights in the invention. 
    
    
     FIELD 
     The invention relates generally to gas pressure regulation, such as ultra-high pressure regulation and particularly to a ultra-high gas pressure regulator and a method of using the same. 
     BACKGROUND 
     A pressure regulator reduces an input pressure of a fluid to a desired output pressure. Generally, the flow of gas through the regulator matches to the demand for the gas while maintaining a constant output gas pressure. The main components of a pressure regulator typically include a restricting element, a loading element, and a measuring element. The restricting element is usually a valve capable of providing a variable restriction to fluid flow. The loading element usually applies a force to the restricting element. The measuring element typically determines when the inlet flow is equal to the outlet flow. 
     Scuba regulators are designed to reduce pressurized breathing gas from a high-pressure cylinder to a pressure that can be inhaled on-demand by a diver. The regulator is capable of supplying breathable gas at a pressure of about 120 to 150 psi from a pressurized tank at a pressure of about 3,000 psi. As such, a series of pressure regulators are employed to reduce the pressure to values that can be delivered for normal respiration. To begin, a cylinder valve (typically with a yoke or DIN fitting) is attached to a diving cylinder to control the flow of high-pressure gas out of the cylinder. A first-stage regulator is mounted on the cylinder valve to reduce the pressure from the tank pressure (up to about 3,000 psi in a traditional tank) to about 120 to about 150 psi above ambient pressure. First-stage scuba regulators employ either a piston or diaphragm sensing element to control outlet gas pressure via flow through a variable-sized orifice. Regardless of type, each sensing element functions by balancing pressure to open and close the valve. 
     Diaphragm regulators are resistant to freezing due to component containment, but are not well suited for high-pressure application. Alternatively, piston regulators are much more robust in design and function. Gas leaving the first-stage regulator at an intermediate pressure is then transferred to a second-stage regulator, which provides breathing gas to a diver&#39;s mouth on-demand at a reduced breathable pressure. 
     SUMMARY 
     These and other needs are addressed by the various embodiments and configurations of the present invention. 
     In accordance with some embodiments is a regulator. The regulator can include a first regulator channel configured to accept a first piston generally having a first piston groove, a last piston groove, and an intermediate piston groove positioned between the first and last piston grooves. The regulator can also include a gas inlet channel interconnected to the first regulator channel and having a gas inlet channel pressure. The last piston groove is commonly positioned adjacent to the gas inlet channel. The last piston groove can contain a last dynamic pressure-sealing element having opposing upper and lower last dynamic pressure-sealing element surfaces. The regulator can include a gas outlet channel having a gas outlet channel pressure. The gas inlet and the gas outlet channels are generally in fluid communication. The first piston groove is typically positioned adjacent to the gas outlet channel. The first piston groove contains a first dynamic pressure-sealing element having opposing upper and lower first dynamic pressure-sealing element surfaces. The intermediate piston groove usually contains an intermediate dynamic sealing element having opposing upper and lower intermediate dynamic sealing element surfaces. The regulator can also include a second regulator channel generally having a second fluid pressure. The second regulator channel can commonly be in fluid communication with the upper last dynamic pressure-sealing element surface and to the lower intermediate dynamic pressure-sealing element surface. The lower last dynamic pressure-sealing element surface is commonly at the gas inlet pressure. The upper first dynamic pressure-sealing element surface is commonly at the gas outlet pressure. Moreover, the upper last dynamic pressure-sealing element surface and the lower intermediate dynamic pressure-sealing element surface are at the second fluid pressure. The lower first dynamic pressure-sealing element surface and the upper intermediate dynamic pressure-sealing element are at a first fluid pressure. Furthermore, the inlet pressure is greater than one or both of the first and second fluid pressures. Moreover, the outlet pressure is no greater than one or both of first and second fluid pressures. 
     The first dynamic pressure-sealing element is usually positioned between upper and lower first back-up rings. The intermediate dynamic pressure-sealing element is commonly positioned between upper and lower intermediate back-up rings. The last dynamic pressure-sealing element is typically positioned between upper and lower last back-up rings. The first dynamic pressure-sealing element can be an o-ring. The first dynamic pressure-sealing element can be a nitrile o-ring. The intermediate dynamic pressure-sealing element can be a nitrile o-ring. The last dynamic pressure-sealing element can be a nitrile o-ring. 
     Commonly, the gas outlet channel pressure can be from about 500 psi to about 5000 psi. More commonly, the gas outlet channel pressure can be from about 1000 psi to about 3000 psi. 
     Typically, the gas inlet channel pressure can be from about 4,500 psi to about 10,000 psi. More typically, the gas inlet channel pressure can be from about 5,000 psi to about 10,000 psi. 
     Commonly, the second fluid pressure can be from about 1,500 to about 5,000 psi. More commonly, the second fluid pressure can be from about 2,000 to about 5,000 psi. Even more commonly, the second fluid pressure can be from about 3,000 to about 5,000 psi. Yet even more commonly, the second first fluid pressure can be about 5,000 psi. Still yet even more commonly, the second fluid pressure can be about 4,000 psi. Yet still even more commonly, the second fluid pressure can be about 6,000 psi. 
     The first fluid pressure can generally be about 1 atm at STP. More generally the first fluid pressure can be from about 0.8 to about 1 atm at STP. 
     In some embodiments, the second regulator channel can be configured to accept a pressure-limiting-valve plug, a pressure-limiting-valve spring cap, a pressure-limiting-valve spring, a pressure-limiting-valve push rod, a pressure-limiting-valve piston, and a pressure-limiting-valve retainer. Furthermore, the pressure-limiting-valve plug can seal the pressure-limiting-valve spring cap, pressure-limiting-valve spring, pressure-limiting-valve push rod, pressure-limiting-valve piston, and pressure-limiting-valve retainer in the second regulator channel. The pressure-limiting spring cap can have a spring cap void. Moreover, the pressure-limiting-valve push rod can have a push rod stem interconnected to a push rod head. A portion of the push rod stem is typically contained within the spring cap void. Furthermore, the pressure-limiting-valve spring can be positioned between the pressure-limiting valve spring cap and the push rod head. The push rod head can be in contact with one end of the pressure-limiting-valve piston. The pressure-limiting-valve retainer can be in contact with the other end of pressure-limiting-valve piston. 
     The first regulator channel can be configured to accept, in addition to the first piston, one or more piston lock washers, a loading force element, a piston seat, and a piston seat retainer. The one or more lock washers can contain one or more lock washer voids and/or channels. Moreover, first piston can have a piston shaft. The first piston shaft can have at one end a piston arm and at other end a piston head. The piston arm and piston head can be in an opposing relationship. The first piston can be positioned between the one or more lock washers and the piston seat. The loading-force element can contain a loading-force element void. A portion of the piston shaft can be positioned in the loading-force element void. The piston seat can be positioned between the piston head and the piston seat retainer. 
     In accordance with some embodiments is a system having an inlet channel for introducing a pressurized gas having an inlet gas pressure. The inlet gas pressure can apply a lifting force to a first piston contained within a first regulator channel. The applied lifting force can also break a gas-tight seal between a first piston seat and the first piston. Moreover, the gas inlet pressure can also apply the inlet gas pressure to a lower last dynamic pressure-sealing element surface of a last dynamic pressure-sealing element. Furthermore, the inlet gas pressure can introduce the pressurized gas into a first piston channel to flow the pressurized gas to an outlet and convert the inlet gas pressure to an outlet gas pressure. The inlet gas pressure can be greater than outlet pressure. Moreover, the first piston channel traverses a first piston longitudinal axis. The system can also include a second regulator channel for applying a second fluid pressure to both the upper last dynamic pressure-sealing element surface and to a lower intermediate dynamic pressure-sealing element surface. The upper and lower last dynamic pressure-sealing element surfaces are typically in an opposing relationship. The inlet gas pressure can be applied to the lower last dynamic pressure-sealing element surface. Moreover, the outlet gas pressure can be applied to upper first dynamic pressure-sealing element surface. The system can generally include a second first gas to apply a first fluid pressure to lower first dynamic pressure-sealing element surface and the upper intermediate dynamic pressure-sealing element surface. The inlet pressure can be greater than one or both of the first and second fluid pressures. The outlet pressure can be no greater than one or both of first and second fluid pressures. 
     The first dynamic pressure-sealing element is usually positioned between upper and lower first back-up rings. The intermediate dynamic pressure-sealing element is commonly positioned between upper and lower intermediate back-up rings. The last dynamic pressure-sealing element is typically positioned between upper and lower last back-up rings. The first dynamic pressure-sealing element can be an o-ring. The first dynamic pressure-sealing element can be a nitrile o-ring. The intermediate dynamic pressure-sealing element can be a nitrile o-ring. The intermediate dynamic pressure-sealing element can be a nitrile o-ring. The last dynamic pressure-sealing element can be a nitrile o-ring. The last dynamic pressure-sealing element can be a nitrile o-ring. 
     Commonly, the pressure applied by the outlet gas pressure can be from about 500 psi to about 5000 psi. More commonly, the pressure applied by the outlet gas pressure is from about 1000 psi to about 3000 psi. 
     Generally, pressure applied by the inlet gas pressure can be from about 4,500 psi to about 10,000 psi. More generally, the pressure applied by the inlet gas pressure can be from about 5,000 psi to about 10,000 psi. 
     Commonly, the pressure applied by the second fluid pressure can be from about 1,500 to about 5,000 psi. More commonly, the pressure applied by the second fluid pressure can be from about 2,000 to about 5,000 psi. Even more commonly, the pressure applied by the second fluid pressure can be from about 3,000 to about 5,000 psi. Still yet even more commonly, the pressure applied by the second fluid pressure is about 5,000 psi. Still yet even more commonly, the pressure applied by the second fluid pressure can be about 4,000 psi. Yet still even more commonly, the pressure applied by the second fluid pressure can be about 6,000 psi. 
     Commonly, the pressure applied by the second fluid pressure can be from about 1,500 to about 5,000 psi. More commonly, the pressure applied by the second fluid pressure can be from about 2,000 to about 5,000 psi. Even more commonly, the pressure applied by the second fluid pressure can be from about 3,000 to about 5,000 psi. Still yet even more commonly, the pressure applied by the second fluid pressure is about 5,000 psi. Still yet even more commonly, the pressure applied by the second fluid pressure can be about 4,000 psi. Yet still even more commonly, the pressure applied by the second fluid pressure can be about 6,000 psi. 
     The pressure applied by the first fluid pressure can typically be about 1 atm at STP. More typically, the pressure applied by the first fluid pressure can be from about 0.8 to about 1 atm at STP. 
     In some embodiments, the second regulator channel can be configured to accept a pressure-limiting-valve plug, a pressure-limiting-valve spring cap, a pressure-limiting-valve spring, a pressure-limiting-valve push rod, a pressure-limiting-valve piston, and a pressure-limiting-valve retainer. Furthermore, the pressure-limiting-valve plug can seal the pressure-limiting-valve spring cap, pressure-limiting-valve spring, pressure-limiting-valve push rod, pressure-limiting-valve piston, and pressure-limiting-valve retainer in the second regulator channel. The pressure-limiting spring cap can have a spring cap void. Moreover, the pressure-limiting-valve push rod can have a push rod stem interconnected to a push rod head. A portion of the push rod stem can typically contained within the spring cap void. Furthermore, the pressure-limiting-valve spring can be positioned between the pressure-limiting valve spring cap and the push rod head. The push rod head can be in contact with one end of the pressure-limiting-valve piston. The pressure-limiting-valve retainer can be in contact with the other end of pressure-limiting-valve piston. 
     The first regulator channel can be configured to accept, in addition to the first piston, one or more piston lock washers, a loading force element, a piston seat, and a piston seat retainer. The one or more lock washers can contain one or more lock washer voids and/or channels. Moreover, first piston can have a piston shaft. The piston shaft can have at one end a piston arm and at other end a piston head. The piston arm and piston head can be in an opposing relationship. The first piston can be positioned between the one or more lock washers and the piston seat. The loading-force element can contain a loading-force element void. A portion of the piston shaft can be positioned in the loading-force element void. The piston seat can be positioned between the piston head and the piston seat retainer. 
     In accordance with some embodiments is a device that includes a first regulator channel configured to accept a first piston having a first piston groove, a last piston groove, and an intermediate piston groove positioned between the first and last piston grooves. The last piston groove can contain a last dynamic pressure-sealing element having upper and lower last dynamic pressure-sealing element surfaces. The upper last dynamic pressure-sealing element surface can be subjected to the second pressure. The lower last dynamic pressure-sealing element surface can be subjected to a fourth pressure. The second and fourth pressures exert different pressure forces on the last dynamic pressure-sealing element. The intermediate piston groove can contain a intermediate dynamic pressure-sealing element having upper and lower intermediate dynamic pressure-sealing element surfaces. The upper intermediate dynamic pressure-sealing element surface can be subjected to the first pressure. The lower intermediate dynamic pressure-sealing element surface can be subjected to a second pressure. The second and first pressures can exert different pressure forces on the intermediate dynamic pressure-sealing element. The first piston groove can contain a first dynamic pressure-sealing element having upper and lower first dynamic pressure-sealing element surfaces. The upper first dynamic pressure-sealing element surface can be subjected to a third pressure. The lower first dynamic pressure-sealing element surface can be subjected to the first pressure. The third and first pressures exert different pressure forces on the first dynamic pressure-sealing element. The fourth pressure is more than first pressure. 
     In some embodiments, the first regulator channel can be configured to accept in addition to the first piston, one or more piston lock washers, a loading force element, and a piston seat. 
     The first dynamic pressure-sealing element is usually positioned between upper and lower first back-up rings. The intermediate dynamic pressure-sealing element is commonly positioned between upper and lower intermediate back-up rings. The last dynamic pressure-sealing element is typically positioned between upper and lower last back-up rings. The first dynamic pressure-sealing element can be an o-ring. The first dynamic pressure-sealing element can be a nitrile o-ring. The intermediate dynamic pressure-sealing element can be an o-ring. The intermediate dynamic pressure-sealing element can be a nitrile o-ring. The last dynamic pressure-sealing element can be an o-ring. The last dynamic pressure-sealing element can be a nitrile o-ring. 
     In some embodiments, the device can further include a first upper back-up ring. The first upper back-up ring can a first upper back-up flat ring surface and a upper first back-up ring contoured surface. The first upper back-up flat ring surface and the first upper back-up ring contoured surface can be in an opposing relationship. Moreover, the device can also include a first lower back-up ring. The first lower back-up ring can have a first lower back-up flat ring surface and a lower first back-up ring contoured surface. The first lower back-up flat ring surface and the first lower back-up ring contoured surface can generally be in an opposing relationship. The first dynamic pressure-sealing element can be in contact with the upper first back-up ring contoured surface and the lower first back-up ring contoured surface. 
     In some embodiments, the device can further include an intermediate upper back-up ring. The intermediate upper back-up ring can have an intermediate upper back-up flat ring surface and an upper intermediate back-up ring contoured surface. The intermediate upper back-up flat ring surface and the intermediate upper back-up ring contoured surface can be in an opposing relationship. Moreover, the device can also include an intermediate lower back-up ring. The intermediate lower back-up ring can have an intermediate lower back-up flat ring surface and a lower intermediate back-up ring contoured surface. The intermediate lower back-up flat ring surface and the intermediate lower back-up ring contoured surface can be in an opposing relationship. 
     In some embodiments, the intermediate dynamic pressure-sealing element can be an o-ring. The intermediate dynamic pressure-sealing element is usually in contact with the upper intermediate back-up ring contoured surface and the lower intermediate back-up ring contoured surface. 
     In accordance with some embodiments, the device can further include a last upper back-up ring. The last upper back-up ring can have a last upper back-up flat ring surface and an upper last back-up ring contoured surface. The last upper back-up flat ring surface and the last upper back-up ring contoured surface can be in an opposing relationship. Moreover, the device can further include a last lower back-up ring. The last lower back-up ring can have a last lower back-up flat ring surface and a lower last back-up ring contoured surface. The last lower back-up flat ring surface and the last lower back-up ring contoured surface can be in an opposing relationship. 
     In some embodiments, the last dynamic pressure-sealing element can be an o-ring. The last dynamic pressure-sealing element is typically in contact with the upper last back-up ring contoured surface and the lower last back-up ring contoured surface. 
     Commonly, the first, second, third and fourth pressures are gas pressures. The first gas can have a first gas pressure. That is, the first gas can exert a first gas pressure. The second gas can have a second gas pressure. That is, the second gas can exert a second gas pressure. The third gas can have a third gas pressure. That is, the third gas can exert a third gas pressure. The fourth gas can have a fourth gas pressure. That is, the fourth gas can exert a fourth gas pressure. 
     In accordance with some embodiments of the present disclosure is a device that includes a first regulator channel configured to accept a first piston. The first piston can have a first piston groove, a last piston groove, and an intermediate piston groove positioned between the first and last piston grooves. Furthermore, the first piston can have an exterior piston wall. The first regulator channel can have a first regulator channel wall. The first piston groove can contain a first dynamic pressure-sealing element, the first dynamic pressure-sealing element can have upper and lower first dynamic pressure-sealing element surfaces. The second piston groove can contain a second dynamic pressure-sealing element, the second dynamic pressure sealing element can have upper and lower second dynamic pressure-sealing element surfaces. The third piston groove can contain a third dynamic pressure-sealing element, the third dynamic pressure sealing element can have upper and lower third dynamic pressure-sealing element surfaces. 
     In accordance with some embodiments is a second regulator volume defined by a second portion of the exterior piston wall, a second portion of the first regulator channel wall, the lower first dynamic pressure-sealing element surface, and the upper intermediate dynamic pressure-sealing element surface. The second regulator volume typically contains a first fluid at a first fluid pressure. 
     In accordance with some embodiments is a first regulator volume defined by a first portion of the exterior piston wall, a first portion of the first regulator channel wall, the lower intermediate dynamic pressure-sealing element surface, and the upper last dynamic pressure-sealing element surface. The first regulator volume typically contains a second fluid at a second fluid pressure. 
     Some embodiments can include a second regulator channel containing a second fluid at a second fluid pressure. The second regulator channel cam be in fluid communication with the second regulator volume. Moreover, the second regulator volume can contain the second fluid at the second fluid pressure. The first and second fluid pressures can differ in pressure. 
     In some embodiments, the device can further include a third regulator volume. The third regulator volume can contain the second fluid at a third fluid pressure. 
     In some embodiments, the device can further include a fourth regulator volume. The fourth regulator volume can contain the second fluid at a fourth fluid pressure. 
     Commonly, the fourth fluid pressure is greater than the third fluid pressure. Generally, the third fluid is a breathable gas supplied by a high-pressure gas source. The high-pressure gas source can usually be a high-pressure tank. More usually, the high-pressure tank can be a self-contained breathing apparatus tank. 
     Commonly, the third fluid pressure can be from about 500 psi to about 5000 psi. More commonly, the gas outlet channel pressure can be from about 1000 psi to about 3000 psi. 
     Typically, the fourth fluid pressure can be from about 4,500 psi to about 10,000 psi. More typically, the fourth fluid pressure can be from about 5,000 psi to about 10,000 psi. Even more typically, the fourth fluid pressure is from about 6,000 to about 10,000 psi. 
     Commonly, the second fluid pressure can be from about 1,500 to about 5,000 psi. More commonly, the second fluid pressure can be from about 2,000 to about 5,000 psi. Even more commonly, the second fluid pressure can from about 3,000 to about 5,000 psi. Even more commonly, the second fluid pressure can be about 5,000 psi. Yet even more commonly, the second fluid pressure can be about 4,000 psi. Still yet even more commonly, the second fluid pressure can be about 6,000 psi. 
     The first fluid pressure can generally be about 1 atm at STP. More generally the first fluid pressure can be from about 0.8 to about 1 atm at STP. Typically, the first fluid pressure is about 1 atm when the first regulator volume is constructed. More typically, the first fluid pressure is about from about 0.8 to about 1 atm at STP when the first regulator volume is constructed. 
     In some embodiments, the second regulator channel can be configured to accept a pressure-limiting-valve plug, a pressure-limiting-valve spring cap, a pressure-limiting-valve spring, a pressure-limiting-valve push rod, a pressure-limiting-valve piston, and a pressure-limiting-valve retainer. Furthermore, the pressure-limiting-valve plug can seal the pressure-limiting-valve spring cap, pressure-limiting-valve spring, pressure-limiting-valve push rod, pressure-limiting-valve piston, and pressure-limiting-valve retainer in the second regulator channel. The pressure-limiting spring cap can have a spring cap void. Moreover, the pressure-limiting-valve push rod can have a push rod stem interconnected to a push rod head. A portion of the push rod stem is typically contained within the spring cap void. Furthermore, the pressure-limiting-valve spring can be positioned between the pressure-limiting valve spring cap and the push rod head. The push rod head can be in contact with one end of the pressure-limiting-valve piston. The pressure-limiting-valve retainer can be in contact with the other end of pressure-limiting-valve piston. 
     The first regulator channel can be configured to accept, in addition to the first piston, one or more piston lock washers, a loading force element, a piston seat, and a piston seat retainer. The one or more lock washers can contain one or more lock washer voids and/or channels. Moreover, first piston can have a piston shaft. The piston shaft can have at one end a piston arm and at other end a piston head. The piston arm and piston head can be in an opposing relationship. The first piston can be positioned between the one or more lock washers and the piston seat. The loading-force element can contain a loading-force element void. A portion of the piston shaft can be positioned in the loading-force element void. The piston seat can be positioned between the piston head and the piston seat retainer. 
     Typically, the first and second fluids are gases. More typically, the first and second fluids are breathable gases. Even more typically, the first and second fluids are breathable gases having from about 75 to about 80 v/v % nitrogen, from about 19 to about 24 v/v % oxygen. Yet even more typically, the first and second fluids differ in one or more of composition and source. Generally, the second fluid source is a high-pressure tank. Usually, the first fluid source is the ambient atmosphere when the first regulator volume is constructed. 
     In some embodiments, the device can further include a first upper back-up ring. The first upper back-up ring can have a first upper back-up flat ring surface and an upper first back-up ring contoured surface. The first upper back-up flat ring surface and the first upper back-up ring contoured surface can be in an opposing relationship. Moreover, the device can also include a first lower back-up ring. The first lower back-up ring can have a first lower back-up flat ring surface and a lower first back-up ring contoured surface. The first lower back-up flat ring surface and the first lower back-up ring contoured surface can generally be in an opposing relationship. The first dynamic pressure-sealing element can be in contact with the upper first back-up ring contoured surface and the lower first back-up ring contoured surface. 
     In some embodiments, the device can further include an intermediate upper back-up ring. The intermediate upper back-up ring can have an intermediate upper back-up flat ring surface and an upper intermediate back-up ring contoured surface. The intermediate upper back-up flat ring surface and the intermediate upper back-up ring contoured surface can be in an opposing relationship. Moreover, the device can also include an intermediate lower back-up ring. The intermediate lower back-up ring can have an intermediate lower back-up flat ring surface and a lower intermediate back-up ring contoured surface. The intermediate lower back-up flat ring surface and the intermediate lower back-up ring contoured surface can be in an opposing relationship. 
     In some embodiments, the intermediate dynamic pressure-sealing element can be an o-ring. The intermediate dynamic pressure-sealing element is usually in contact with the upper intermediate back-up ring contoured surface and the lower intermediate back-up ring contoured surface. 
     In accordance with some embodiments, the device can further include a last upper back-up ring. The last upper back-up ring can have a last upper back-up flat ring surface and a upper last back-up ring contoured surface. The last upper back-up flat ring surface and the last upper back-up ring contoured surface can be in an opposing relationship. Moreover, the device can further include a last lower back-up ring. The last lower back-up ring can have a last lower back-up flat ring surface and a lower last back-up ring contoured surface. The last lower back-up flat ring surface and the last lower back-up ring contoured surface can be in an opposing relationship. 
     In some embodiments, the last dynamic pressure-sealing element can be an o-ring. The last dynamic pressure-sealing element is typically in contact with the upper last back-up ring contoured surface and the lower last back-up ring contoured surface. 
     In accordance with some embodiments is a method that includes in a regulator having first piston positioned in a first regulator channel, the first piston having a first piston channel in fluid communication with a gas inlet having a fourth gas pressure and gas outlet having a third gas pressure. In some embodiments, the first piston is moveable. Some embodiments, in a first piston position, flow of the gas through the first piston channel is substantially blocked when the third gas pressure at the gas outlet is above a selected pressure, and, in a second piston position, flow of the gas through the first piston channel is permitted until the gas pressure at the gas outlet is at the third pressure and less than the selected pressure, maintaining, when the first piston is in both the first and second piston positions, a first gas pressure between a first and intermediate piston grooves. Some embodiments can include maintaining, when the movable piston is in both the first and second piston positions, a second gas pressure between the intermediate and last piston grooves. The intermediate piston groove can be positioned between the first and last piston grooves. The second gas pressure can be greater than the first gas pressure. In some embodiments, each of the first gas pressure, second gas pressure, gas inlet pressure and gas outlet pressure are different from one another. 
     The present invention can provide a number of advantages depending on the particular configuration. 
     These and other advantages will be apparent from the disclosure of the invention(s) contained herein. 
     As used herein, “at least one”, “one or more”, and “and/or” are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B and C”, “at least one of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B, or C”, “A, B, and/or C”, and “A, B, or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together. When each one of A, B, and C in the above expressions refers to an element, such as X, Y, and Z, or class of elements, such as X 1 -X n , Y 1 -Y m , and Z 1 -Z o , the phrase is intended to refer to a single element selected from X, Y, and Z, a combination of elements selected from the same class (e.g., X 1  and X 2 ) as well as a combination of elements selected from two or more classes (e.g., Y 1  and Z o ). 
     It is to be noted that the term “a” or “an” entity refers to one or more of that entity. As such, the terms “a” (or “an”), “one or more” and “at least one” can be used interchangeably herein. It is also to be noted that the terms “comprising”, “including”, and “having” can be used interchangeably. 
     The term “means” as used herein shall be given its broadest possible interpretation in accordance with 35 U.S.C., Section 112(f) and/or Section 112, Paragraph 6. Accordingly, a claim incorporating the term “means” shall cover all structures, materials, or acts set forth herein, and all of the equivalents thereof. Further, the structures, materials or acts and the equivalents thereof shall include all those described in the summary of the disclosure, brief description of the drawings, detailed description, abstract, and claims themselves. 
     Unless otherwise noted, all component or composition levels are in reference to the active portion of that component or composition and are exclusive of impurities, for example, residual solvents or by-products, which may be present in commercially available sources of such components or compositions. 
     All percentages and ratios are calculated by total composition weight, unless indicated otherwise. 
     It should be understood that every maximum numerical limitation given throughout this disclosure is deemed to include each and every lower numerical limitation as an alternative, as if such lower numerical limitations were expressly written herein. Every minimum numerical limitation given throughout this disclosure is deemed to include each and every higher numerical limitation as an alternative, as if such higher numerical limitations were expressly written herein. Every numerical range given throughout this disclosure is deemed to include each and every narrower numerical range that falls within such broader numerical range, as if such narrower numerical ranges were all expressly written herein. By way of example, the phrase from about 2 to about 4 includes the whole number and/or integer ranges from about 2 to about 3, from about 3 to about 4 and each possible range based on real (e.g., irrational and/or rational) numbers, such as from about 2.1 to about 4.9, from about 2.1 to about 3.4, and so on. 
     The preceding is a simplified summary of the invention to provide an understanding of some aspects of the invention. This summary is neither an extensive nor exhaustive overview of the invention and its various embodiments. It is intended neither to identify key or critical elements of the invention nor to delineate the scope of the invention but to present selected concepts of the invention in a simplified form as an introduction to the more detailed description presented below. As will be appreciated, other embodiments of the invention are possible utilizing, alone or in combination, one or more of the features set forth above or described in detail below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings are incorporated into and form a part of the specification to illustrate several examples of the present disclosure(s). These drawings, together with the description, explain the principles of the disclosure(s). The drawings simply illustrate preferred and alternative examples of how the disclosure(s) can be made and used and are not to be construed as limiting the disclosure(s) to only the illustrated and described examples. Further features and advantages will become apparent from the following, more detailed, description of the various embodiments of the disclosure(s), as illustrated by the drawings referenced below. 
         FIGS. 1A and 1B  depict an elevated view of a regulator according to some embodiments of the present disclosure; 
         FIG. 2  depicts an exploded view of a regulator according to some embodiments of the present disclosure; 
         FIG. 3A  depicts a top plan view of a regulator according to some embodiments of the present disclosure; 
         FIG. 3B  depicts an elevated view of a regulator of  FIGS. 1A and 1B  interconnected to a fluid source according to some embodiments of the present disclosure; 
         FIG. 3C  depicts a cross-sectional view of  FIG. 3B  according to some embodiments of the present disclosure; 
         FIG. 4A  depicts a top plan view of a regulator according to some embodiments of the present disclosure; 
         FIG. 4B  depicts an elevated cut-away section of  FIG. 4A  according to some embodiments of the present disclosure; 
         FIG. 5A  depicts a top plan view of a regulator according to some embodiments of the present disclosure; 
         FIG. 5B  depicts a cross-sectional view of  FIG. 5A  according to some embodiments of the present disclosure; 
         FIG. 5C  depicts another cross-sectional view of  FIG. 5A  according to some embodiments of the present disclosure; 
         FIG. 5D  depicts another cross-sectional view of  FIG. 5A  according to some embodiments of the present disclosure; 
         FIG. 6A  depicts a top plan view of a regulator according to some embodiments of the present disclosure; 
         FIG. 6B  depicts an elevated cut-away section of  FIG. 6A  according to some embodiments of the present disclosure; 
         FIG. 7  depicts a cross-sectional view according to some embodiments of the present disclosure; 
         FIG. 8  depicts a cross-sectional view according to some embodiments of the present disclosure; 
         FIG. 9  depicts a cross-sectional view according to some embodiments of the present disclosure; 
         FIG. 10  depicts a cross-sectional view according to some embodiments of the present disclosure; 
         FIG. 11  depicts a cross-sectional view according to some embodiments of the present disclosure; 
         FIG. 12  depicts a cross-sectional view according to some embodiments of the present disclosure; 
         FIGS. 13A-13C  depict a cross-sectional view according to some embodiments of the present disclosure and 
         FIG. 14  depicts a cross-sectional view according to some embodiments of the present disclosure and 
         FIG. 15  depicts a cross-sectional view according to some embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Current tank first-stage regulators are not designed for operation at pressures above about 4,300 psi. As such, a need exists for a tank regulator that can reduce a pressure of more than about 4,300 psi to a much lower pressure. In accordance with some embodiments of the present disclosure, a pressure regulator as described herein can reduce a gas pressure from one of more than about 4,300 psi to a much lower pressure of about 1,200 psi or lower. Such a gas regulator has a regulator body that contains an interior piston assembly to control fluid flow through the regulator. The gas regulator can provide a substantially controlled outlet pressure gas flow from a gas source having a substantially greater pressure than the controlled outlet pressure, such as but not limited to a gas source pressure of about 10,000 psi and a controlled outlet pressure of about 1,200 psi or lower. Furthermore, the outlet pressure of the pressure regulator remains substantially unaffected by variations in the relatively high pressure from the gas source. 
     Some embodiments of the disclosure include a gas regulator for a self-contained or compressed air breathing apparatus, such as typically used by divers, rescue workers, firefighters, paint-booth operators, welders, sandblasters, aircraft workers, chemical plant operators, and others needing breathable air in an environment where breathing is generally dangerous to life or health. Such breathing apparatuses typically have a high-pressure source, such as a tank, interconnected and in fluid communication with an inhalation device. The high-pressure tank usually has an initial pressure of from between about 2,215 to about 4,000 psi. The inhalation device is generally one of a mouthpiece, a mouth mask, a facemask or a combination thereof. 
     In accordance with some embodiments, the high-pressure tank can have an initial pressure of one of commonly more than about 4,100 psi, more commonly of more than about 4,250 psi, even more commonly of more than about 4,500 psi, yet even more commonly of more than about 5,000 psi, still yet even more commonly of more than about 6,000 psi, still yet even more commonly of more than about 7,000 psi, still yet even more commonly of more than about 8,000 psi, still yet even more commonly of more than about 9,000 psi, still yet even more commonly of more than about 10,000 psi, still yet even more commonly of more than about 11,000 psi, or yet still even more commonly of more than about 12,000 psi. 
     In accordance with some embodiments, the high-pressure tank can have an initial pressure of between one of generally more than about 4,100 psi, more generally of more than about 4,250 psi, even more generally of more than about 4,500 psi, yet even more generally of more than about 5,000 psi and one of generally no more than about 4,500 psi, yet even more generally of no more than about 5,000 psi, still yet even more generally of no more than about 6,000 psi, still yet even more generally of no more than about 7,000 psi, still yet even more generally of no more than about 8,000 psi, still yet even more generally of no more than about 9,000 psi, still yet even more generally of no more than about 10,000 psi, still yet even more generally of no more than about 11,000 psi, or yet still even more generally of no more than about 12,000 psi. 
     The high-pressure tank can be an ultra-high-pressure composite tank. The ultra-high-pressure tank can comprise a composite material wall construction. The composite material wall construction can increase structural integrity of the ultra-high-pressure composite tank and achieve a light-weight tank. The increased pressure in such a composite tank can provide over double the breathing time of a single traditional tank. As such, the breathing time of the tank can be substantially increased, in some instances by about a factor of one of about 50%, 75%, 100%, or even more. 
     The breathable air contained in the tank is typically supplied in accordance with Occupational Safety and Health Standards, specifically according to one of OSHA 1910.134, OSHA 1910.430, Compressed Gas Associate Grade D, Compressed Gas Associate Grade E, Compressed Gas Associate Grade 1, CGA Grade D, NFGA 1989, or combination thereof. In some embodiments, the breathable air comprises one of compressed air, compressed oxygen, liquid air, liquid oxygen, or a combination thereof. In some embodiments, the breathable air meets the United States Pharmacopoeia requirements for medical or breathing oxygen. In some embodiments, the breathable air can have one or more of: an oxygen content (v/v) of from about 19.5 to about 23.5%; a hydrocarbon (condensed) content of about 5 milligrams per cubic meter of air or less; a carbon monoxide (CO) content of about 10 ppm or less; a carbon dioxide content of about 1,000 ppm or less; and no noticeable odor. In some embodiments, the breathable air can have one or more of: a level of carbon monoxide (CO) of no more than about 20 ppm; a level of carbon dioxide (CO 2 ) of no more than about 1,000 ppm; a level of oil mist of no more than about 5 milligrams per cubic meter; and no noxious or pronounced odor. In some embodiments the breathable air has a dew point not to exceed −50 degrees Fahrenheit. In some embodiments the breathable air has a dew point not to exceed −65 degrees Fahrenheit. Generally, the oxygen content of the breathable gas can be from about 19.5 to 23.5 v/v %, more generally from about 20 to about 22 v/v %. The breathable gas commonly contains one of from about 75 to about 80 v/v % nitrogen, more commonly from about 76.5 to about 80.5 v/v % nitrogen, or even more commonly form about 78 to about 80 v/v %. The carbon monoxide content of the breathable gas can be from about 5 to 10 ppm. In some embodiments, the breathable gas can have a carbon monoxide content of one of no more than about 10 ppm or of no more than about 5 ppm. The carbon dioxide content of the breathable gas can be from about 1,000 to 500 ppm. In some embodiments, the breathable gas can have a carbon dioxide content of one of no more than about 1,000 ppm or of no more than about 500 ppm. The total hydrocarbon content, usually as methane, of the breathable gas is typically no more than about 25 ppm. The breathable gas can have a condensed-oil content of about 5 mg/m 3  at NTP. In some embodiments, the breathable gas can have a condensed oil and particulate content of 2 mg/m 3  at NPT. The breathable gas can have a nitric oxide content of about 2.5 ppm. The breathable gas can have a nitrous dioxide content of about 2.5 ppm. The breathable gas can have a sulfur dioxide content of about 5 ppm. The water content of the breathable gas can generally be no more than about 67 ppm, more generally no more than about 24 ppm. The dew point of the breathable gas is usually no more than about −50 degrees Fahrenheit, more usually no more than about −65 degrees Fahrenheit. 
     A self-contained breathing apparatus can be one or more of an open circuit and closed circuit breathing apparatus. 
       FIGS. 1-15  depict a pressure regulator  100  in accordance with some embodiments of the present disclosure. The pressure regulator  100  comprises a regulator body  13 . The regulator body  13  generally has a cylindrical shape with a regulator wall  101  and opposing upper  102  and lower  103  surfaces. Extending through the regulator body  13  from the upper surface  102  to the lower surface  103  surfaces are first  104  and second  105  regulator channels. Generally, a third regulator channel  106  also extends through the regulator body  13 . The third regulator channel  106  also extends through the regulator body  13  from the upper surface  102  to the lower surface  103 . 
     The regulator body  13  can comprise one of brass, a brass alloy, aluminum, an aluminum alloy, stainless steel, a stainless steel alloy, a stainless steel SAE Type 303 alloy, a stainless steel SAE Type 304 alloy, or a stainless SAE Type steel  316  alloy. Commonly, the regulator body  13  comprises stainless steel. More commonly, the regulator body  13  comprises a stainless steel alloy. Even more commonly, the regulator body  13  comprises a stainless steel alloy selected from the group consisting essentially of a stainless steel SAE Type 303 alloy, a stainless steel SAE Type 304 alloy, and a stainless steel SAE Type 316 alloy. 
     The pressure regulator  100  can have a regulator wall groove  107 . The regulator wall groove  107  circumscribes the cylindrical wall of the regulator body  13 . Generally, the regulator wall groove  107  comprises first  108  and second  109  regulator wall grooves. In some configurations, the first regulator wall groove  108  is deeper than the second regulator wall groove  109 . Yet in some configurations, the second regulator wall groove  109  is deeper than the first regulator wall groove  108 . Regulator wall groove  107  is configured to interconnect the regulator body  13  to a high-pressure gas source  110 . In some configurations, the first  108  and second  109  regulator wall grooves are configured to interconnect the regulator body  13  to a high-pressure gas source  110 . The regulator body  13  can be interconnected to the high-pressure gas source  110  by one or more of most commonly, a threaded port with 10,000 psi custom o-ring seal, a bolted flange connection, a flange clamp, or least commonly, a welded interface. 
     The regulator body  13  commonly has a gas inlet channel  111  interconnected to the first regulator channel  104 . It can be appreciated that the gas inlet channel  111  and the first regulator channel  104  are in fluid communication. The gas inlet channel  111  is generally positioned below the regulator wall groove  107  and closer to lower surface  103  than upper surface  102 . The gas inlet channel  111  is generally positioned below first  108  and second  109  grooves and closer to lower surface  103  than upper surface  102 . The gas inlet channel  111  is commonly in the form of a channel. The gas inlet can have first  112  and second  113  gas inlet apertures. The first gas inlet aperture  112  is commonly position on the regulator wall  101 . In some configurations, the first gas inlet aperture  112  can be positioned on lower surface  103  (not depicted in figures). The second gas inlet aperture  113  is positioned on the first regulator channel  104 . 
     The first regulator channel  104  is configured to accept a first piston  22 , one or more piston lock washers  23 , a loading force element  27 , and a piston seat  16 . The first piston  22  and the one or more piston lock washers  23  generally comprise one of brass, a brass alloy, aluminum, an aluminum alloy, stainless steel, a stainless steel alloy, a stainless steel SAE Type 303 alloy, a stainless steel SAE Type 304 alloy, or a stainless steel SAE Type 316 alloy. Commonly, the first piston  22  and the one or more piston lock washers  23  comprise stainless steel. More commonly, the first piston  22  and the one or more piston lock washers  23  comprise a stainless steel alloy. Even more commonly, the first piston  22  and the one or more piston lock washers  23  comprise a stainless steel alloy selected from the group consisting essentially of a stainless steel SAE Type 303 alloy, a stainless steel SAE Type 304 alloy, and a stainless steel SAE Type 316 alloy. 
     The load force element  27  is generally a spring. The load force element  27  usually comprises one of carbon steel, a carbon steel alloy, stainless steel, a stainless steel alloy, a stainless steel SAE Type 303 alloy, a stainless steel SAE Type 304 alloy, or a stainless steel SAE Type 316 alloy. More usually, the load force element  27  comprises a stainless steel alloy selected from the group consisting essentially of a stainless steel SAE Type 303 alloy, a stainless steel SAE Type 304 alloy, and a stainless steel SAE Type 316 alloy. Likewise, the spring generally comprises one of carbon steel, a carbon steel alloy, stainless steel, a stainless steel alloy, a stainless steel SAE Type 303 alloy, a stainless steel SAE Type 304 alloy, or a stainless steel SAE Type 316 alloy. More generally, the spring comprises a stainless steel alloy selected from the group consisting essentially of a stainless steel SAE Type 303 alloy, a stainless steel SAE Type 304 alloy, and a stainless steel SAE Type 316 alloy. 
     The piston seat  16  can be substantially any material. Typically, the piston seat  16  comprises one of carbon-filled PEEK (polyether ether ketone), carbon-filled CTFE (polychlorotrifluroethylene), fluorocarbon, polytetrafluoroethylene, ethylene propylene diene rubber, silicione, a perfluoroelastomeric material, a polyimide, a polyimide loaded with graphite, a polyimide loaded with graphite and polytetrafluoroethylene, a polyimide loaded with molybdenum disulfide, an unloaded polyimide, a polyimide loaded with 15 wt % graphite, a polyimide loaded with 40 wt % graphite, a polyimide loaded with 15 wt % graphite and 10 wt % polytetrafluoroethylene, a polyimide loaded with 15 wt % molybdenum disulfide. More typically, the piston seat  16  comprises one of a polyimide, a polyimide loaded with graphite, a polyimide loaded with graphite and polytetrafluoroethylene, a polyimide loaded with molybdenum disulfide, an unloaded polyimide, a polyimide loaded with 15 wt % graphite, a polyimide loaded with 40 wt % graphite, a polyimide loaded with 15 wt % graphite and 10 wt % polytetrafluoroethylene, a polyimide loaded with 15 wt % molybdenum disulfide. The piston seat  16  can have a thermal expansion coefficient of from about 34 to about 45×10 −6 /K at temperatures from about 211 to about 296 degrees Kelvin and/or from about 38 to about 54×10 −6 /K at temperatures from about 296 to about 573 degrees Kelvin. The piston seat  16  can have a thermal conductivity at about 313 degrees Kelvin from about 0.35 to about 1.75 W/mK. More over, the piston seat  16  can have a volume resistivity at about 296 degrees Kelvin of one of from about 10 12  to about 10 15  ohms-m, from about 10 12  to about 10 13  ohms-m, or from about 10 14  to about 10 15  ohms-m. Furthermore, the piston seat  16  can have a dielectric constant of from about 3.6 to about 13.5 at about 100 Hz, from about 3.65 to about 13.3 at about 10 kHz, from about 3.6 to about 13.4 at 1 MHz, or a combination thereof. 
     The first piston  22  comprises piston shaft  116  having interior  121  and an exterior  122  walls. The interior wall  121  defines a piston channel  120 . One end of the piston shaft  116  has a piston arm  114  extending from the piston shaft  116  and having opposing upper  123  and lower  124  piston arm surfaces. The upper piston arm surface  123  can contain a first countersink piston void  115  interconnect with the piston channel  120 . The first countersink piston void  115  and piston channel  120  are in fluid communication. The other end of the piston shaft  116  comprises piston head  118 . The piston head  118  is distal to and in an opposing relationship with the piston arm  114 . It can be appreciated that the piston head  118  and piston arm  114  are at opposing ends of the piston shaft  116 . The piston head  118  can contain a second countersink piston void  117 . The second countersink piston void  117  is interconnected with the piston channel  120 . It can be further appreciated that the second countersink piston void  117  and the piston channel  120  are in fluid communication. Moreover, the distal end of the piston head  118  has a sharp piston head edge  155 . It can be appreciated that in some embodiments the piston channel  120  extends the entire length of the first piston  22  from the upper piston arm surface  123  to the distal end of the piston head  118  sharp piston head edge  155 . The first piston  22  can be a moveable piston. 
     The first piston  22  may or may not have three or more first piston grooves  119   a - 119   c . In some configurations, the first piston  22  may free of any of the three or more first piston grooves  119   a - 119   c.    
     In some configurations, the first piston may have the three or more first piston grooves  119   a - 119   c . In some embodiments, the first piston arm  114  has the first  119   a  of the three or more first piston groove and the first piston shaft  116  has the last  119   c  and an intermediate  119   b  of the three or more of the first piston grooves. Each of the three or more of the first piston grooves  119   a - 119   c  are configured respectively to accept a dynamic pressure seals  20   a - c . The dynamic pressure seals  20   a - c  typically comprise an o-ring. The dynamic pressure seals  20   a - c  can be selected from the group of o-rings comprising nitrile. buna-N, Viton, EPDM, and perflourolastomer. 
     Generally, the three or more of the first piston grooves  119   a - 119   c  can also be configured to accept a dynamic pressure seals  20   a - c  positioned between upper  18   a - c  and lower  19   a - c  back-up rings. It can be appreciated that the first piston arm  114  can have a circumference that is typically greater than the piston shaft  116  circumference. Hence, the pressure seal  20   a  and its respective upper  18   a  and lower  19   a  back-up rings positioned in the first of the three or more piston groove  119   a  are greater in size than pressure seals  20   b  and  20   c  and their respective upper  18   b  and  18   c  and lower  19   a  and  19   c  back-up rings positioned in the other of the three or more first piston grooves  119   b  and  119   c.    
     In some configurations, the first piston  22  can have three piston grooves, a first piston groove  119   a , an intermediate piston groove  119   b , and a last piston groove  119   c . In some embodiments, the first piston arm  114  has the first piston groove  119   a  and the first piston shaft  116  has the intermediate piston groove  119   b  and the last piston groove  119   c . Each of the three piston grooves  119   a - 119   c  are configured to accept respective dynamic pressure seals  20   a - 20   c . The dynamic pressure seals  20   a - 20   c  typically comprise o-rings. The dynamic pressure seals  20   a - 20   c  can be selected from the group of o-rings comprising nitrile. buna-N, Viton, EPDM, and perflourolastomer. 
     Generally, the three piston grooves  119   a - 119   c  can also be configured, respectively, to accept dynamic pressure seals  20  positioned between upper  18  and lower  19  back-up rings. It can be appreciated that the first piston arm  114  can have a circumference that is typically greater than that of the piston shaft  116  circumference. Hence, the pressure seal  20   a  and its respective upper  18   a  and lower  19   a  back-up rings positioned in the first piston groove  119   a  are greater in size than pressure seals  20   b - 20   c  and their respective upper  18   b - 18   c  and lower  19   b - 19   c  back-up rings positioned in the intermediate  119   b  and the last  119   c  piston grooves. 
     In some configurations where the first piston is free of any first piston grooves, the first regulator channel  104  contains first regular channel grooves  124   a - c . The first regular channel grooves  124   a - c  are configured to accept the dynamic pressure seals  20   a - c . In some configurations, the first regular channel grooves  124   a - c  are configured to accept a dynamic pressure seal  20  positioned between upper  18  and lower  19  back-up rings. 
     The first regulator channel  104  can comprise no more than six regulator channel segments  104   a - f . The regular channel segment  104   a  is positioned at the top-end of the regulator channel  104  and is configured to accept valve o-ring  24 . Regulator channel segment  104   b , which is configured to accept valve  25 , is positioned between regulator channels segments  104   a  and  104   c . The regulator channel segment  104   c  is configured to accept the one or more piston lock washers  23 . Immediately below regulator channel segment  104   c  is regulator channel segment  104   d , which is positioned above regulator channel segment  104   e.    
     The one or more piston lock washers  23  are configured to limit movement of the first piston  22 , more particularly translational movement of the first piston  22  within the first regulator channel  104 . The one or more piston lock washers  23  commonly contain one or more lock washer voids and/or channels  128 . Hence, the one or more piston lock washers  23  can allow for fluid communication from one side of one or more lock washers  23  to an opposing side of the one or more lock washers  23 . 
     Regulator channel segment  104   d  is configured to accept the first piston arm  114  and the loading force element  27 . The regulator channel segment  104   d  extends from at least the upper piston arm surface  123  to no more than the top of the intermediate of the three or more of the first piston groove  119   b . In some configurations where first piston  22  has three or more first piston grooves  119   a - c , the regulator channel segment  104   d  is configured to accept the first piston arm  114  with the dynamic pressure seal  20   a  positioned in the first of the three or more of the piston grooves  119   a . In some configurations where the first piston  22  is free of any of the three or more first piston grooves  119   a - c , the regulator channel  104   d  is configured to accept the first piston arm  114  and contains a first regulator channel groove  124   a  containing a dynamic pressure seal  20   a.    
     The regulator channel  104   e , which is positioned between regulator channels  104   d  and  104   f , is configured to accept the first piston shaft  116 . The regulator channel  104   e  extends from at least the top of the intermediate of the three or more of the first piston grooves  119   b  to the bottom of the last of the three or more of the first piston grooves  119   c . In some configurations where first piston  22  has three or more first piston grooves  119   a - c , the regulator channel  104   e  is configured to accept the first piston shaft  116  with the dynamic pressure seals  20   b - c  positioned respectively in the first piston grooves  119   b - c . In some configurations where the first piston  22  is free of any first piston grooves  119   a - c , the regulator channel  104   e  is configured to accept the first piston shaft  116  and contains one or more first regulator channel grooves  124  with each containing a dynamic pressure seal  20 . 
     The dynamic pressure seals  20   a - c  are sized and configured to create a gap  125  between the first piston  22  and first regulator channel wall  140 . The gap  125  can commonly be from one of more than about 0.0005 inch, more commonly more than about 0.001 inch, even more commonly more than about 0.0015 inch, yet even more commonly than about 0.002, still yet even more commonly more than about 0.0025 inch, still yet even more commonly more than about 0.003 inch, still yet even more commonly more than about 0.0035 inch, still yet even more commonly more than about 0.004 inch, still yet even more commonly more than about 0.0045 inch, still yet even more commonly more than about 0.005 inch, still yet even more commonly more than about 0.0055 inch, still yet even more commonly more than about 0.006 inch, still yet even more commonly more than about 0.0065 inch, still yet even more commonly more than about 0.007 inch, still yet even more commonly more than about 0.0075 inch, still yet even more commonly more than about 0.008 inch, still yet even more commonly more than about 0.0085 inch, or yet still even more commonly more than about 0.009 inch to commonly one of no more than about 0.001 inch, more commonly be one of no more than about 0.0015 inch, even more commonly be one of no more than about 0.002 inch, yet even more commonly be one of no more than about 0.0025 inch, still yet even more commonly be one of no more than about 0.003 inch, still yet even more commonly be one of no more than about 0.0035 inch, still yet even more commonly be one of no more than about 0.004 inch, still yet even more commonly be one of no more than about 0.0045 inch, still yet even more commonly be one of no more than about 0.005 inch, still yet even more commonly be one of no more than about 0.0055 inch, still yet even more commonly be one of no more than about 0.006 inch, still yet even more commonly be one of no more than about 0.0065 inch, still yet even more commonly be one of no more than about 0.007 inch, still yet even more commonly be one of no more than about 0.0075 inch, still yet even more commonly be one of no more than about 0.008 inch, commonly be one of no more than about 0.0085 inch, still yet even more commonly be one of no more than about 0.009 inch, still yet even more commonly be one of no more than about 0.0095 inch, or yet still even more commonly be one of no more than about 0.01 inch. 
     In accordance with embodiments of the present disclosure, the dynamic pressure seals  20   a - c  substantially impede gas flow from one side  202  of the dynamic pressure seal  20  to the opposing side  204  of the dynamic pressure seal  20 . Accordingly, the gas pressure in gap  125  on the one side  202  of the dynamic pressure seal  20  can be greater than the gas pressure on the opposing side  204  of the dynamic pressure seal  20 , or vice-a-versa. The dynamic pressure seals in pressure regulators of the prior art commonly fail when the pressure difference between the opposing sides of the pressure seal are greater than about 3,000 to about 5,000 psi. Hence, dynamic pressure seals generally fail when inlet gas (or gas source) pressure is greater than about 5,000 psi and/or when the difference between the inlet gas (or gas source) pressure and outlet gas pressure is greater than about 5,000 psi. The pressure regulator  100  of the present disclosure allows for one or both of inlet gas (or gas source) pressures greater than about 5,000 psi and/or for a difference between the inlet gas (or gas source) pressure and outlet gas pressure of more than about 5,000 psi. 
     In accordance with some embodiments, the gas pressure on the one side  202  of the dynamic pressure seal  20  is typically one of about 4,000 psi or more than the gas pressure on the opposing side  204  of the dynamic pressure seal  20 , more typically about 4,500 psi or more, even more typically about 5,000 psi or more, yet even more typically about 5,500 psi or more, still yet even more typically about 6,000 psi or more, still yet even more typically about 7,500 psi or more, still yet even more typically about 8,000 psi or more, still yet even more typically about 8,000 psi or more, still yet even more typically about 9,000 psi or more, or yet still even more typically about 10,000 psi or more. Generally, the gas pressure on the one side  202  of the dynamic pressure seal  20  is one of more than about 4,000 psi greater than the gas pressure on the opposing side  204  of the dynamic pressure seal  20 , more generally more than about 4,500 psi, even more generally more than about 5,000 psi, yet even more generally more than about 5,500 psi, still yet even more generally more than about 6,000 psi, still yet even more generally more than about 6,500 psi, still yet even more generally more than about 7,000 psi, still yet even more generally more than about 8,000 psi, still yet even more generally more than about 9,000 psi, or yet still even more generally more than about 10,000 psi and one of typically no more than about 4,500 psi, more typically no more than about 5,000 psi, even more typically no more than about 5,500 psi, yet even more typically no more than about 6, 000 psi, still yet even more typically no more than about 6,500 psi, still yet even more typically no more than about 7,000 psi, still yet even more typically no more than about 8,000 psi, still yet even more typically no more than about 9,000 psi, still yet even more typically no more than about 10,000 psi, or yet still even more typically no more than about 11,000 psi. In accordance with some embodiments, the gas pressure on the opposing side  204  of the dynamic pressure seal  20  is commonly one of about 4,000 psi or more than the gas pressure on the opposing side  202  of the dynamic pressure seal  20 , more commonly about 4,500 psi or more, even more commonly about 5,000 psi or more, yet even more commonly about 5,500 psi or more, still yet even more commonly about 6,000 psi or more, still yet even more commonly about 7,500 psi or more, still yet even more commonly about 8,000 psi or more, still yet even more commonly about 8,000 psi or more, still yet even more commonly about 9,000 psi or more, or yet still even more commonly about 10,000 psi or more. 
     Regulator channel  104   f  is configured to accept piston seat retainer  15  and the piston seat  16 . The piston seat retainer  15  is configured to contain and retain the piston seat  16 . The piston seat retainer  15  can be interconnected to the regulator body  13 . Furthermore, the piston seat retainer  15  can have a retainer gas inlet channel  127 . The retainer gas inlet channel  127  can allow one side of the piston seat  16  to be subject to the gas source pressure. The gas inlet channel  111  can allow the piston seat side that is in an opposing relationship to the one side of the piston seat to also be subjected to the gas source pressure. Accordingly, the pressure on the one side and the opposing side of the piston seat  16  are at substantially the same pressure. That is the pressures on the one side and the opposing side of the piston seat  16  is substantially are substantially about same, that is both pressures are substantially about the gas source pressure. 
     Regulator channel  105  is configured to accept a pressure-limiting-valve plug  2 , a pressure-limiting-valve spring cap, a pressure-limiting-valve spring  129 , a pressure-limiting-valve push rod  4 , a pressure-limiting-valve piston  8 , and a pressure-limiting-valve retainer  14 . The pressure-limiting-valve retainer  14  has a pressure-limiting-valve gas inlet  130 . The pressure-limiting-valve gas inlet  130  can allow the gas contained in the gas source to enter a first channel volume  132  of the regulator channel  105 . The pressure-liming-valve push rod  4 , the pressure-liming-valve spring  129 , and the pressure-limiting-valve piston  8  can be configured to allow gas contained in the first channel volume  132  to enter and be in fluid communication with first internal regulator channel  131  and the gap  125  defined the dynamic pressure seals  20   b - c  to contained in first piston grooves  119   b  and  119   c . Gas contained in the first channel volume  132  can also enter and be in fluid communication with the first internal regulator channel  131  and the gap  125  defined the dynamic pressure seals  20   b - c  respectively contained in the intermediate  119   b  and the last  119   c  of the three or more of the first piston grooves  119   b  and  119   c . Gas can enter and be in fluid communication with the first internal regulator channel  131  and the gap  125  as long as the pressure in the first internal regulator channel  131  and the gap  125  is below the predetermined value. When the pressure of the gas in one or more of the first regulator channel  131  and the gap  125  is one or more of at or below the predetermined pressure value, the pressure-liming-valve push rod  4 , the pressure-liming-valve spring  129 , and the pressure-limiting-valve piston  8  are configured to substantially block the gas contained in the first channel volume  132  from entering and being in fluid communication with one or more of the first internal regulator channel  131  and the gap  125 . 
     The first internal regulator channel  131  can interconnect a first external wall aperture  132  and the regulator channel  105 . A first channel plug  17   a  can be positioned in the first external wall aperture  132 . The first channel plug  17   a  substantially can seal the first external wall aperture  132  and can substantially not allow any gas to enter the first internal regulator channel  131  through the first external wall aperture  132 . 
     Second  132  and third  133  internal regulator channels can be in fluid communication with the first internal regulator channel  131 . The second internal regulator channel  132  can interconnect and can be in fluid communication with the first internal regulator channel  131 . The second internal regulator channel  132  can also interconnect a second external wall aperture  134  with the first internal regulator channel  131 . A second channel plug  17   b  can be positioned in the first external wall aperture  134 . The second channel plug  17   b  can substantially seal the second external wall aperture  134  and can substantially not allow gas to enter the second internal regulator channel  132  through the second external wall aperture  134 . 
     The third internal regulator channel  133  can interconnect and can be in fluid communication with the second internal regulator channel  132 . The third internal regulator channel  133  can also interconnect a first upper surface aperture  135  with the second internal regulator channel  132  and a third channel plug  1 . A third channel plug  1  can be positioned in first upper surface aperture  135 . The third channel plug  1  can substantially seal the first upper surface aperture  135  and can substantially not allow any gas to enter the third internal regulator channel  133  through the first upper surface aperture  135 . 
     In some embodiments, the regulator body  13  can contain second  136  and third  137  upper surface apertures. The second  136  and third  137  upper surface apertures are configured to accept a tool for interconnecting the pressure regulator  100  to one or more of a gas source or regulator testing system. 
     The third regulator channel  106  is generally adapted to accept a pressure transducer  10  and transducer micro-connector  9 . The pressure transducer  10  is sealed within the third regulator channel  106  by a transducer o-ring  12  and transducer coupling  10 . The pressure transducer  10  is positioned between the transducer o-ring  12  and transducer coupling  10 . The transducer-connector  9  is mechanically interconnected to the transducer coupling  10  and electrically interconnected to the pressure transducer  10 . In some embodiments, an o-ring is positioned between the transducer micro-connector  9  and the transducer coupling  10 . 
       FIG. 12  depicts a dynamic a pressure seal, such as one of dynamic pressure seals  20   a - c , positioned respectively between upper  18  and lower back-up rings, such a one of the upper  18   a - c  and lower  19   a - c  back-up rings, according some embodiments of the present disclosure.  FIG. 12  further depicts a dynamic pressure seal  20  with its upper  18  and lower  19  back-up rings position in a piston groove  119  of piston  22 . According to some embodiments, the upper  18  and lower  19  back-up rings each have a contoured surface  411  and an opposing flat surface  413 . A dynamic pressure seal  20  is commonly positioned between and in contact with the respective contoured surfaces  411  of the upper  18  and lower  19  back-up rings. 
     It is believed that controlling one or more of a piston gap distance  125  can substantially increase the pressure difference between 202 and 204 before the dynamic pressure seal  20  fails. For example, selecting one or more of a piston gap distance  125  from the group consisting of from about 0.0005 to about 0.005 inch, 0.0005 to about 0.004 inch, 0.0005 to about 0.003 inch, 0.0005 to about 0.002 inch, from about 0.001 to about 0.004 inch, 0.001 to about 0.003 inch, 0.001 to about 0.002 inch, and from about 0.002 to about 0.003 inch, and can generally increase the difference between 202 and 204 to one of more than about 6,0000 psi, even more generally to more than about 7,000 psi, yet even more generally to more than about 8,000 psi, still yet even more generally to more than about 9,000 psi, still yet even more generally to more than about 10,000 psi, or yet still even more generally to more than about 11,000 psi before the dynamic pressure seal  20  fails. 
     Stated another way, selecting one or more of a piston gap distance  125  from the group consisting of from about 0.0005 to about 0.005 inch, 0.0005 to about 0.004 inch, 0.0005 to about 0.003 inch, 0.0005 to about 0.002 inch, from about 0.001 to about 0.004 inch, 0.001 to about 0.003 inch, 0.001 to about 0.002 inch, and from about 0.002 to about 0.003 inch, can generally increase the difference between 202 and 204 to typically one of from about 4,000 to about 10,500 psi, more typically from about 5,000 to about 10,000 psi, even more from about 5,000 to about 10,000 psi, yet even more typically from about 6,000 to about 9,50 psi, still yet even more typically from about 6,000 to about 9,000 psi, or yet still even more typically from about 6,500 to about 9,000 psi before the dynamic pressure seal  20  fails. 
     It can be appreciated that the piston-based regulator  100 , a piston  22 , spring  27 , and piston seat  16  act together to seal the high-pressure inlet gas from the low-pressure outlet  150 , accomplished by balancing pressure forces acting on the piston  22 . When the outlet pressure is low, the spring forces the piston  22  off the piston seat  16 , opening the regulator for gas flow. Gas flows through the piston  22 , increasing the outlet pressure. When the outlet pressure reaches the set point, the increased gas pressure forces the piston  22  against the seat  16 , stopping gas flow. In current first-stage piston type scuba regulators, a single o-ring between the piston and regulator body is used to create a seal preventing unwanted flow of high-pressure gas to the spring housing. These o-rings, while capable of maintaining a pressure differential typical in current scuba systems (of about 3,000 to about 4,000 psi), would rupture if employed at pressure from about 5,000 to about 10,000 psi. 
     In accordance with some embodiments is a regulator  100 . The regulator  100  can include a first regulator channel  104  configured to accept a first piston  22  generally having a first piston groove  119   a , a last piston groove  119   c , and an intermediate piston groove  119   b  positioned between the first  119   a  and last piston grooves  119   c . The regulator  100  can also include a gas inlet channel  111  interconnected to the first regulator channel  104  and having a gas inlet channel pressure. The last piston groove  119   c  is commonly positioned adjacent to the gas inlet channel  111 . The last piston groove  119   c  can contain a last dynamic pressure-sealing element  20   c  having opposing upper  224   a  and lower  224   b  last dynamic pressure-sealing element surfaces. The regulator  100  can include a gas outlet channel  150  having a gas outlet channel pressure. The gas inlet channel  111  and the gas outlet channel  150  are generally in fluid communication. The first piston groove  119   a  is typically positioned adjacent to the gas outlet channel  150 . The first piston groove  119   a  contains a first dynamic pressure-sealing element  20   a  having opposing upper  220   a  and lower  220   b  first dynamic pressure-sealing element surfaces. The intermediate piston groove  119   b  usually contains an intermediate dynamic sealing element  20   b  having opposing upper  222   a  and lower  222   b  intermediate dynamic sealing element surfaces. The regulator  100  can also include a second regulator channel  105  generally having a second fluid pressure. The second regulator channel can commonly be in fluid communication with the upper last dynamic pressure-sealing element surface  224   a  (positioned in the first piston groove  119   c ) and to the lower intermediate dynamic pressure-sealing element surface  222   b  (positioned in the intermediate first piston groove  119   b ). The lower last dynamic pressure-sealing element surface  224   b  (positioned in the last piston groove  119   c ) is commonly subjected to the gas inlet pressure. The upper first dynamic pressure-sealing element surface  220   a  (positioned in the last piston groove  119   a ) is commonly subjected to the gas outlet pressure. Moreover, the upper last dynamic pressure-sealing element surface  224   a  (positioned in the first piston groove  119   c ) and the lower intermediate dynamic pressure-sealing element surface  222   b  (positioned in the intermediate piston groove  119   b ) are at the second fluid pressure. The lower first dynamic pressure-sealing element surface  220   b  (positioned in the last piston groove  119   a ) and the upper intermediate dynamic pressure-sealing element  222   a  (positioned in the intermediate first piston groove  119   b ) are at a first fluid pressure. Furthermore, the inlet pressure is greater than one or both of the first and second fluid pressures. Moreover, the outlet pressure is no greater than one or both of first and second fluid pressures. 
     The first dynamic pressure-sealing element  20   a  is usually positioned between upper  18   a  and lower  19   b  first back-up rings. The intermediate dynamic pressure-sealing element  20   b  is commonly positioned between upper  18   b  and lower  19   b  intermediate back-up rings. The last dynamic pressure-sealing element  20   c  is typically positioned between upper  18   c  and lower  19   c  last back-up rings. The first dynamic pressure-sealing element  20   a  can be an o-ring. The first dynamic pressure-sealing element  20   a  can be a nitrile o-ring. The intermediate dynamic pressure-sealing element  20   b  can be an o-ring. The intermediate dynamic pressure-sealing element  20   b  can be a nitrile o-ring. The last dynamic pressure-sealing element  20   c  can be an o-ring. The last dynamic pressure-sealing element  20   c  can be a nitrile o-ring. 
     Commonly, the gas outlet channel  150  pressure can be from about 100 psi to about 500 psi. More commonly, the gas outlet channel  150  pressure can be from about 120 psi to about 150 psi. 
     Typically, the gas inlet channel  111  pressure can be from about 4,500 psi to about 10,000 psi. More typically, the gas inlet channel  111  pressure can be from about 5,000 psi to about 10,000 psi. 
     Commonly, the second fluid pressure can be from about 1,500 to about 5,000 psi. More commonly, the second fluid pressure can be from about 2,000 to about 5,000 psi. Even more commonly, the second fluid pressure can be from about 3,000 to about 5,000 psi. Yet even more commonly, the second fluid pressure can be about 5,000 psi. Still yet even more commonly, the second fluid pressure can be about 4,000 psi. Yet still even more commonly, the second fluid pressure can be about 6,000 psi. 
     The first fluid pressure can generally be about 1 atm at STP. More generally the first fluid pressure can be from about 0.8 to about 1 atm at STP. 
     In some embodiments, the second regulator channel  105  can be configured to accept a pressure-limiting-valve plug  2 , a pressure-limiting-valve spring cap  3 , a pressure-limiting-valve spring  129 , a pressure-limiting-valve push rod  4 , a pressure-limiting-valve piston  8 , and a pressure-limiting-valve retainer  14 . Furthermore, the pressure-limiting-valve plug  2  can seal the pressure-limiting-valve spring cap  3 , pressure-limiting-valve spring  129 , pressure-limiting-valve push rod  4 , pressure-limiting-valve piston  8 , and pressure-limiting-valve retainer  14  in the second regulator channel  105 . The pressure-limiting valve spring cap  3  can have a spring cap void  151 . Moreover, the pressure-limiting-valve push rod  4  can have a push rod stem  152  interconnected to a push rod head  153 . A portion of the push rod stem  152  is typically contained within the spring cap void  151 . Furthermore, the pressure-limiting-valve spring  129  can be positioned between the pressure-limiting valve spring cap  3  and the push rod head  153 . The push rod head  153  can be in contact with one end of the pressure-limiting-valve piston  8 . The pressure-limiting-valve retainer  14  can be in contact with the other end of pressure-limiting-valve piston  8 . 
     The first regulator channel  104  can be configured to accept, in addition to the first piston  22 , one or more piston lock washers  23 , a loading force element  27 , a piston seat  16 , and a piston seat retainer  15 . The one or more lock washers  23  can contain one or more lock washer voids and/or channels  128 . Moreover, first piston  22  can have a piston shaft  116 . The piston shaft  116  can have at one end a piston arm  114  and at other end a piston head  118 . The piston arm  114  and piston head  118  can be in an opposing relationship. The first piston  22  can be positioned between the one or more lock washers  23  and the piston seat  16 . The loading-force element  27  can contain a loading-force element void  154 . A portion of the piston shaft  116  can be positioned in the loading-force element void  154 . The piston seat  16  can be positioned between the piston head  118  and the piston seat retainer  15 . 
     In accordance with some embodiments is system having an inlet channel  111  for introducing a pressurized gas having an inlet gas pressure. The inlet gas pressure can apply a lifting force to a first piston  22  contained within a first regulator channel  104 . The applied lifting force can also break a gas-tight seal between a first piston seat  16  and the first piston  22 . Moreover, the inlet gas pressure can also apply the inlet gas pressure to a lower last dynamic pressure-sealing element surface  224   b  of a last dynamic pressure-sealing element  20   c . Furthermore, the inlet gas pressure can introduce the pressurized gas into a first piston channel  120  to flow the pressurized gas to a gas outlet  150  and convert the inlet gas pressure to an outlet gas pressure. The inlet gas pressure can be greater than outlet pressure. Moreover, the first piston channel  120  traverses a first piston longitudinal axis. The system can also include a second regulator channel  105  for applying a second fluid pressure to both the upper last dynamic pressure-sealing element surface  224   a  and to a lower intermediate dynamic pressure-sealing element surface  222   b . The upper  224   a  and lower  224   b  last dynamic pressure-sealing surfaces are typically in an opposing relationship. The inlet gas pressure can be applied to the lower last dynamic pressure-sealing element surface  224   b . Moreover, the outlet gas pressure can be applied to upper first dynamic pressure-sealing element surface  220   a . The system can generally include a first pressurized gas to apply a first fluid pressure to lower first dynamic pressure-sealing element surface  220   b  and the upper intermediate dynamic pressure-sealing element surface  222   a . The inlet pressure can be greater than one or both of the first and second fluid pressures. The outlet pressure can be no greater than one or both of first and second fluid pressures. 
     The first dynamic pressure-sealing element  20   a  is usually positioned between upper  18   a  and lower  19   b  first back-up rings. The intermediate dynamic pressure-sealing element  20   b  is commonly positioned between upper  18   b  and lower  19   b  intermediate back-up rings. The last dynamic pressure-sealing element  20   c  is typically positioned between upper  18   c  and lower  19   c  last back-up rings. The first dynamic pressure-sealing element  20   a  can be an o-ring. The first dynamic pressure-sealing element  20   a  can be a nitrile o-ring. The intermediate dynamic pressure-sealing element  20   b  can be an o-ring. The intermediate dynamic pressure-sealing element  20   b  can be a nitrile o-ring. The last dynamic pressure-sealing element  20   c  can be an o-ring. The last dynamic pressure-sealing element  20   c  can be a nitrile o-ring. 
     Commonly, the pressure applied by the outlet gas pressure can be from about 100 psi to about 500 psi. More commonly, the pressure applied by the outlet gas pressure is from about 120 psi to about 150 psi. 
     Generally, pressure applied by the inlet gas pressure can be from about 4,500 psi to about 10,000 psi. More generally, the pressure applied by the inlet gas pressure can be from about 5,000 psi to about 10,000 psi. 
     The pressure applied by the first fluid pressure can typically be about 1 atm at STP. More typically, the pressure applied by the first fluid pressure can be from about 0.8 to about 1 atm at STP. 
     In some embodiments, the second regulator channel  105  can be configured to accept a pressure-limiting-valve plug  2 , a pressure-limiting-valve spring cap  3 , a pressure-limiting-valve spring  129 , a pressure-limiting-valve push rod  4 , a pressure-limiting-valve piston  8 , and a pressure-limiting-valve retainer  14 . Furthermore, the pressure-limiting-valve plug  2  can seal the pressure-limiting-valve spring cap  3 , pressure-limiting-valve spring  129 , pressure-limiting-valve push rod  4 , pressure-limiting-valve piston  8 , and pressure-limiting-valve retainer  14  in the second regulator channel  105 . The pressure-limiting valve spring cap  3  can have a spring cap void  151 . Moreover, the pressure-limiting-valve push rod  4  can have a push rod stem  152  interconnected to a push rod head  153 . A portion of the push rod stem  152  is typically contained within the spring cap void  151 . Furthermore, the pressure-limiting-valve spring  129  can be positioned between the pressure-limiting valve spring cap  3  and the push rod head  153 . The push rod head  153  can be in contact with one end of the pressure-limiting-valve piston  8 . The pressure-limiting-valve retainer  14  can be in contact with the other end of pressure-limiting-valve piston  8 . 
     The first regulator channel  104  can be configured to accept, in addition to the first piston  22 , one or more piston lock washers  23 , a loading force element  27 , a piston seat  16 , and a piston seat retainer  15 . The one or more lock washers  23  can contain one or more lock washer voids and/or channels  128 . Moreover, first piston  22  can have a piston shaft  116 . The piston shaft  116  can have at one end a piston arm  114  and at other end a piston head  118 . The piston arm  114  and piston head  118  can be in an opposing relationship. The first piston  22  can be positioned between the one or more lock washers  23  and the piston seat  16 . The loading-force element  27  can contain a loading-force element void  154 . A portion of the piston shaft  116  can be positioned in the loading-force element void  154 . The piston seat  16  can be positioned between the piston head  118  and the piston seat retainer  15 . 
     In accordance with some embodiments is a device that includes a first regulator channel  104  configured to accept a first piston  22  having a first piston groove  119   a , a last piston groove  119   c , and an intermediate piston groove  119   b  positioned between the first  119   a  and last  119   c  piston grooves. The last piston groove  119   c  can contain a last dynamic pressure-sealing element  20   c  having upper  224   a  and lower  224   b  last dynamic pressure-sealing element surfaces. The upper last dynamic pressure-sealing element surface  224   a  can be subjected to a second pressure. The lower last dynamic pressure-sealing element surface  224   b  can be subjected to a fourth pressure. The first and fourth pressures exert different pressure forces on the last dynamic pressure-sealing element  20   c . The intermediate piston groove  119   b  can contain an intermediate dynamic pressure-sealing element  20   b  can have upper  222   a  and lower  222   b  second dynamic pressure-sealing element surfaces. The upper intermediate dynamic pressure-sealing element surface  222   a  can be subjected to the first pressure. The lower dynamic pressure-sealing element surface  222   b  can be subjected to the second pressure. The second and first pressures can exert different pressure forces on the intermediate dynamic pressure-sealing element  20   b . The first piston groove  119   a  can contain a first dynamic pressure-sealing element  20   a  having upper  220   a  and lower  220   b  first dynamic pressure-sealing element surfaces. The upper first dynamic pressure-sealing element surface  220   a  can be subjected to a third pressure. The lower first dynamic pressure-sealing element surface  220   a  can be subjected to the first pressure. The third and first pressures exert different pressure forces on the first dynamic pressure-sealing element  20   a . The fourth pressure is more than first pressure. 
     The first pressure can generally be about 1 atm at STP. More generally the first pressure can be from about 0.8 to about 1 atm at STP. 
     Commonly, the second pressure can be from about 1,500 to about 5,000 psi. More commonly, the second pressure can be from about 2,000 to about 5,000 psi. Even more commonly, the second pressure can from about 3,000 to about 5,000 psi. Even more commonly, the second pressure can be about 5,000 psi. Yet even more commonly, the second pressure can be about 4,000 psi. Still yet even more commonly, the second pressure can be about 6,000 psi. 
     Commonly, the third pressure can be from about 100 psi to about 150 psi. More commonly, the gas outlet channel  150  pressure can be from about 120 psi to about 150 psi. 
     Generally, fourth pressure can be from about 4,500 psi to about 10,000 psi. More generally, the fourth pressure can be from about 5,000 psi to about 10,000 psi. Even more generally, the fourth pressure can be from about 6,000 to about 10,000 psi. Yet even more generally, the fourth pressure can be from about 7,000 to about 10,000 psi. 
     In some embodiments, the first regulator channel  104  can be configured to accept in addition to the first piston  22 , one or more piston lock washers  23 , a loading force element  27 , and a piston seat  16 . 
     The first dynamic pressure-sealing element  20   a  is usually positioned between upper  18   a  and lower  19   b  first back-up rings. The intermediate dynamic pressure-sealing element  20   b  is commonly positioned between upper  18   b  and lower  19   b  intermediate back-up rings. The last dynamic pressure-sealing element  20   c  is typically positioned between upper  18   c  and lower  19   c  last back-up rings. The first dynamic pressure-sealing element  20   a  can be an o-ring. The first dynamic pressure-sealing element  20   a  can be a nitrile o-ring. The intermediate dynamic pressure-sealing element  20   b  can be a nitrile o-ring. The last dynamic pressure-sealing element  20   c  can be a nitrile o-ring. 
     In some embodiments, the device can further include a first upper back-up ring  18   a . The first upper back-up ring  18   a  can have a first upper back-up ring  18   a  flat ring surface  413  and an upper first back-up ring  18   a  contoured surface  411 . The first upper back-up flat ring surface  413   a  and the first upper back-up ring  18   a  contoured surface  411  can be in an opposing relationship. Moreover, the device can also include a first lower back-up ring  19   a . The first lower back-up ring  19   a  can have a first lower back-up flat ring  19   a  flat surface  413  and a lower first back-up ring  19   a  contoured surface  411 . The first lower back-up ring  19   a  flat ring surface  413  and the first lower back-up ring  19   a  contoured surface  411  can generally be in an opposing relationship. The first dynamic pressure-sealing element  20   a  can be in contact with the upper first back-up ring  18   a  contoured surface  411  and the lower first back-up ring  19   a  contoured surface  411 . 
     In some embodiments, the device can further include an intermediate upper back-up ring  18   b . The intermediate upper back-up ring  18   b  can have an intermediate upper back-up ring  18   b  flat surface  413  and an upper intermediate back-up ring  18   b  contoured surface  411 . The intermediate upper back-up ring  18   b  flat surface  413  and the intermediate upper back-up ring  18   b  contoured surface  411  can be in an opposing relationship. Moreover, the device can also include an intermediate lower back-up ring  19   b . The intermediate lower back-up ring  19   b  can have an intermediate lower back-up ring  19   b  flat surface  413  and a lower intermediate back-up ring  19   b  contoured surface  411 . The intermediate lower back-up ring  19   b  flat surface  413  and the intermediate lower back-up ring  19   b  contoured surface  411  can be in an opposing relationship. 
     In some embodiments, the intermediate dynamic pressure-sealing element  20   b  can be an o-ring. The intermediate dynamic pressure-sealing element  20   b  is usually in contact with the upper intermediate back-up ring  19   b  contoured surface  411  and the lower intermediate back-up ring  19   b  contoured surface  411 . 
     In accordance with some embodiments, the device can further include a last upper back-up ring  18   c . The last upper back-up ring  18   c  can have a last upper back-up ring  18   c  flat surface  413  and an upper last back-up ring  18   c  contoured surface  411 . The last upper back-up ring  18   c  flat surface  413  and the last upper back-up ring  18   c  contoured surface  411  can be in an opposing relationship. Moreover, the device can further include a last lower back-up ring  19   c . The last back-up ring  19   c  can have a last lower back-up ring  19   c  flat surface  413  and a lower last back-up ring  19   c  contoured surface  411 . The last lower back-up ring  19   c  flat surface  413  and the last lower back-up ring  19   c  contoured surface  411  can be in an opposing relationship. 
     In some embodiments, the last dynamic pressure-sealing element  20   c  can be an o-ring. The last dynamic pressure-sealing element  20   c  is typically in contact with the upper last back-up ring  18   c  contoured surface  411  and the lower last back-up ring  19   c  contoured surface  411 . 
     Commonly, the first, second, third and fourth pressures are gas pressures. The first gas can have a first gas pressure. That is, the first gas can exert a first gas pressure. The second gas can have a second gas pressure. That is, the second gas can exert a second gas pressure. The third gas can have a third gas pressure. That is, the third gas can exert a third gas pressure. The fourth gas can have a fourth gas pressure. That is, the fourth gas can exert a fourth gas pressure. 
     In accordance with some embodiments of the present disclosure is a device that includes a first regulator channel  104  configured to accept a first piston  22 . The first piston  22  can having a first piston groove  119   a , a last piston groove  119   c , and an intermediate piston groove  119   b  positioned between the first  110   a  and last  119   c  piston grooves. Furthermore, the first piston  22  can have an exterior piston wall  122 . The first regulator channel  104  can have a first regulator channel wall  140 . The first piston groove  119   a  can contain a first dynamic pressure-sealing element  20   a , the first dynamic pressure-sealing element  20   a  can have upper  220   a  and lower  220   b  first dynamic pressure-sealing element surfaces. The intermediate piston groove  119   b  can contain an intermediate dynamic pressure-sealing element  20   b , the intermediate dynamic pressure-sealing element  20   b  can have upper  222   a  and lower  222   b  intermediate dynamic pressure-sealing element surfaces. The last piston groove  119   c  can contain a last dynamic pressure-sealing element  20   c , the last dynamic pressure-sealing element  20   c  can have upper  224   a  and lower  224   b  last dynamic pressure-sealing element surfaces. 
     In accordance with some embodiments is a second regulator volume  192  defined by a second portion  193  of the exterior piston wall  190 , a second portion  191  of the first regulator channel wall  140 , the lower first dynamic pressure-sealing element surface  220   b , and the upper intermediate dynamic pressure-sealing element surface  222   a . The second regulator volume  192  typically contains a first fluid at a first fluid pressure. 
     In accordance with some embodiments is a first regulator volume  194  defined by a first portion  195  of the exterior piston wall  190 , a first portion  196  of the first regulator channel wall  140 , the lower intermediate dynamic pressure-sealing element surface  222   b , and the upper last dynamic pressure-sealing element surface  224   a.    
     Some embodiments can include a second regulator channel  105  containing a second fluid at a second fluid pressure. The second regulator channel  105  can be in fluid communication with the second regulator volume  192 . Furthermore, second regulator volume  192  can contain the second fluid at the second fluid pressure. The first and second fluid pressures can differ in pressure. 
     In some embodiments, the device can further include a third regulator volume  197 . The third regulator volume can contain the second fluid at a third fluid pressure. 
     In some embodiments, the device can further include a fourth regulator volume  198 . The fourth regulator volume can contain the second fluid at a fourth fluid pressure. 
     Commonly, the fourth fluid pressure is greater than the third fluid pressure. Generally, the third fluid is a breathable gas supplied by a high-pressure gas source. The high-pressure gas source can usually be a high-pressure tank. More usually, the high-pressure tank can be a self-contained breathing apparatus tank. 
     Commonly, the third fluid pressure can be from about 5000 psi to about 5000 psi. More commonly, the gas outlet channel  150  pressure can be from about 1000 psi to about 3000 psi. 
     Typically, the fourth fluid pressure can be from about 4,500 psi to about 10,000 psi. More typically, the second fluid pressure can be from about 5,000 psi to about 10,000 psi. Even more typically, the second fluid pressure is from about 6,000 to about 10,000 psi. 
     Commonly, the second fluid pressure can be from about 1,500 to about 5,000 psi. More commonly, the second fluid pressure can be from about 2,000 to about 5,000 psi. Even more commonly, the second fluid pressure can from about 3,000 to about 5,000 psi. Even more commonly, the second fluid pressure can be about 5,000 psi. Yet even more commonly, the second fluid pressure can be about 4,000 psi. Still yet even more commonly, the second fluid pressure can be about 6,000 psi. 
     The first fluid pressure can generally be about 1 atm at STP. More generally the first fluid pressure can be from about 0.8 to about 1 atm at STP. Typically, the first fluid pressure is about 1 atm when the second regulator volume  192  is constructed. More typically, the first fluid pressure is about from about 0.8 to about 1 atm at STP when the second regulator volume  192  is constructed. 
     In some embodiments, the second regulator channel  105  can be configured to accept a pressure-limiting-valve plug  2 , a pressure-limiting-valve spring cap  3 , a pressure-limiting-valve spring  129 , a pressure-limiting-valve push rod  4 , a pressure-limiting-valve piston  8 , and a pressure-limiting-valve retainer  14 . Furthermore, the pressure-limiting-valve plug  2  can seal the pressure-limiting-valve spring cap  3 , pressure-limiting-valve spring  129 , pressure-limiting-valve push rod  4 , pressure-limiting-valve piston  8 , and pressure-limiting-valve retainer  14  in the second regulator channel  105 . The pressure-limiting valve spring cap  3  can have a spring cap void  151 . Moreover, the pressure-limiting-valve push rod  4  can have a push rod stem  152  interconnected to a push rod head  153 . A portion of the push rod stem  152  is typically contained within the spring cap void  151 . Furthermore, the pressure-limiting-valve spring  129  can be positioned between the pressure-limiting valve spring cap  3  and the push rod head  153 . The push rod head  153  can be in contact with one end of the pressure-limiting-valve piston  8 . The pressure-limiting-valve retainer  14  can be in contact with the other end of pressure-limiting-valve piston  8 . 
     The first regulator channel  104  can be configured to accept, in addition to the first piston  22 , one or more piston lock washers  23 , a loading force element  27 , a piston seat  16 , and a piston seat retainer  15 . The one or more lock washers  23  can contain one or more lock washer voids and/or channels  128 . Moreover, first piston  22  can have a piston shaft  116 . The piston shaft  116  can have at one end a piston arm  114  and at other end a piston head  118 . The piston arm  114  and piston head  118  can be in an opposing relationship. The first piston  22  can be positioned between the one or more lock washers  23  and the piston seat  16 . The loading-force element  27  can contain a loading-force element void  154 . A portion of the piston shaft  116  can be positioned in the loading-force element void  154 . The piston seat  16  can be positioned between the piston head  118  and the piston seat retainer  15 . 
     Typically, the first and second fluids are gases. More typically, the first and second fluids are breathable gases. Even more typically, the first and second fluids are breathable gases having from about 75 to about 80 v/v % nitrogen, from about 19 to about 24 v/v % oxygen. Yet even more typically, the first and second fluids differ in one or more of composition and source. Generally, the second fluid source is a high-pressure tank. Usually, the first fluid source is the ambient atmosphere when the second regulator volume  192  is constructed. 
     In some embodiments, the device can further include a first upper back-up ring. The first upper back-up ring can have a first upper back-up ring  18   a  flat surface  413  and a upper first back-up ring  18   a  contoured surface  413 . The first upper back-up ring  18   a  flat surface  413  and the first upper back-up ring  18   a  contoured surface  411  can be in an opposing relationship. Moreover, the device can also include a first lower back-up ring  19   a . The first lower back-up ring  19   a  can have a first lower back-up ring  19   a  flat surface  413  and a lower first back-up ring  19   a  contoured surface  413 . The first lower back-up ring  19   a  flat surface  413  and the first lower back-up ring  19   a  contoured surface  413  can generally be in an opposing relationship. The first dynamic pressure-sealing element  20   a  can be in contact with the upper first back-up ring  18   a  contoured surface  411  and the lower first back-up ring  19   a  contoured surface  411 . 
     In some embodiments, the device can further include an intermediate upper back-up ring  18   b . The intermediate upper back-up ring  18   b  can have an intermediate upper back-up ring  18   b  flat surface  413  and a upper intermediate back-up ring  18   b  contoured surface  411 . The intermediate upper back-up ring  18   b  flat surface  413  and the intermediate upper back-up ring  18   b  contoured surface  411  can be in an opposing relationship. Moreover, the device can also include an intermediate lower back-up ring  19   b . The intermediate lower back-up ring  19   b  can have a second lower back-up ring  19   b  flat surface  413  and a lower intermediate back-up ring  19   b  contoured surface  411 . The intermediate lower back-up ring  19   b  flat surface  413  and the intermediate lower back-up ring  19   b  contoured surface  411  can be in an opposing relationship. 
     In some embodiments, the intermediate dynamic pressure-sealing element  20   b  can be an o-ring. The intermediate dynamic pressure-sealing element  20   b  is usually in contact with the upper intermediate back-up ring  18   b  contoured surface  411  and the lower intermediate back-up ring  19   b  contoured surface  411 . 
     In accordance with some embodiments, the device can further include a last upper back-up ring  18   c . The last upper back-up ring  18   c  can have a last upper back-up ring  18   c  flat surface  413  and a upper last back-up ring  18   c  contoured surface  411 . The last upper back-up ring  18   c  flat surface  413  and the last upper back-up ring  18   c  contoured surface  411  can be in an opposing relationship. Moreover, the device can further include a last lower back-up ring  19   c . The last lower back-up ring  19   c  can have a last lower back-up ring  19   c  flat surface  413  and a lower last back-up ring  19   c  contoured surface  411 . The last lower back-up ring  19   c  flat surface  413  and the last lower back-up ring  19   c  contoured surface  411  can be in an opposing relationship. 
     In some embodiments, the last dynamic pressure-sealing element  20   c  can be an o-ring. The last dynamic pressure-sealing element  20   c  is typically in contact with the upper third back-up ring  18   c  contoured surface  43  and the lower third back-up ring  19   c  contoured surface  411 . 
     In accordance with some embodiments is a method that includes in a regulator  100  having first piston  22  positioned in a first regulator channel  105 , the first piston  22  having a first piston channel  120  in fluid communication with a gas inlet  111  having a fourth gas pressure and gas outlet  150  having a third gas pressure. In some embodiments, the first piston  22  is moveable. Some embodiments, in a first piston position, flow of the gas through the first piston channel  120  is substantially blocked when the third gas pressure at the gas outlet  150  is above a selected pressure, and, in a second piston position, flow of the gas through the first piston channel  120  is permitted until the gas pressure at the gas outlet  150  is at the third pressure less than the selected pressure, maintaining, when the first piston  22  is in both the first and second piston positions, a first gas pressure between a first  119   a  and intermediate  119   b  piston grooves. Some embodiments can include maintaining, when the movable piston is in both the first and second piston positions, a second gas pressure between the intermediate  119   b  and last  119   c  piston grooves. The intermediate piston groove  119   b  can be positioned between the first  119   a  and last  119   c  piston grooves. The second gas pressure can be greater than the first gas pressure. In some embodiments, each of the first gas pressure, second gas pressure, gas inlet pressure and gas outlet pressure are different from one another. 
     As described herein, an intermediate chamber can have mediate pressure differentials of more than about 4,000 psi, such as pressure from about 5,000 to about 10,000 psi. By including such an intermediate chamber and one or more additional o-rings between the piston  22  and regulator body, the additional pressure can be stepped-down to an intermediate pressure (such as but not limited to about 5,000 psi) before reaching the spring housing, which is open to ambient pressure. In such configurations, each o-ring experiences a maximum pressure differential of no more than about 5,000 psi, and thus allowing for regulators capable of withstanding higher pressures. The configurations described herein are not limited to a single intermediate pressure chamber, as multiple pressure chambers could be implemented to reduce the pressure differential experienced by any given o-ring further or to increase the maximum operating pressure. The intermediate chamber is pressure controlled by an integrated pressure-limiting valve that feeds the chamber between the high and low-pressure chambers. The pressure-limiting valve is configured such that as the tank is filled the valve is open until the set point (such as but not limited to about 5,000 psi) pressure is attained. Once the set-point pressure is reached the valve closes, sealing the intermediate pressure chamber. Alternatively, as the pressure drops (such as during use), the pressure-limiting valve will remain closed until the tank pressure drops below the set point, at which point the valve opens, maintaining appropriate pressure differentials across the respective o-rings. 
     The regulator as described herein allows for pressure to be reduced from the high pressure inlet (5,000 psi or more) to the low-pressure outlet (for example 2,000 psi). In this configuration, channeling and intermediate chambers are implemented to provide step-down pressures along the piston. This enables the use of o-rings to hold an overall pressure of more than about 5,000 psi pressure differential between the high pressure inlet and the ambient pressure spring housing. The pressures in the above-described intermediate chambers are maintained by a pressure-limiting valve to control the pressure differentials across piston o-rings. These o-rings allow the piston to actuate while maintaining a seal between the various pressure chambers. 
     The piston design needs to accommodate for extremely high pressures of the inlet gas, up to and possibly more than about 10,000 psi. The piston  22  actuates, allowing high-pressure gas to flow and expand to a decreased pressure appropriate for feeding a standard first-stage regulator (having an operating pressure of from about 500 to about 3,000 psi). The piston  22  operates by opening or closing by balancing the forces of high and low pressure gas with that of a compressed spring. When the piston closes, it needs to properly seat and seal to prevent the flow of gas. The seat material, design, and shape to maintain a seal between the high and low-pressure sides of the regulator. 
     A number of variations and modifications of the invention can be used. It would be possible to provide for some features of the invention without providing others. The present invention, in various embodiments, configurations, or aspects, includes components, methods, processes, systems and/or apparatus substantially as depicted and described herein, including various embodiments, configurations, aspects, sub-combinations, and subsets thereof. Those of skill in the art will understand how to make and use the present invention after understanding the present disclosure. The present invention, in various embodiments, configurations, and aspects, includes providing devices and processes in the absence of items not depicted and/or described herein or in various embodiments, configurations, or aspects hereof, including in the absence of such items as may have been used in previous devices or processes, e.g., for improving performance, achieving ease and\or reducing cost of implementation. 
     The foregoing discussion of the invention has been presented for purposes of illustration and description. The foregoing is not intended to limit the invention to the form or forms disclosed herein. In the foregoing Detailed Description for example, various features of the invention are grouped together in one or more embodiments, configurations, or aspects for the purpose of streamlining the disclosure. The features of the embodiments, configurations, or aspects of the invention may be combined in alternate embodiments, configurations, or aspects other than those discussed above. This method of disclosure is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment, configuration, or aspect. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate preferred embodiment of the invention. 
     Moreover, though the description of the invention has included description of one or more embodiments, configurations, or aspects and certain variations and modifications, other variations, combinations, and modifications are within the scope of the invention, e.g., as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intended to obtain rights which include alternative embodiments, configurations, or aspects to the extent permitted, including alternate, interchangeable and/or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and/or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter.