Patent Publication Number: US-8534312-B2

Title: Gas control device with protective cover

Description:
BACKGROUND 
     The invention relates to a gas delivery device for coupling to a pressurized gas source or pressure vessel, such as a pressurized cylinder used for storage and transportation of medical and industrial gases. 
     Generally, high-purity gases are used in many industries, such as manufacturing, in electronic applications, and in the medical field. These gases are typically provided to users in pressurized cylinders that may be configured to be highly transportable for use in laboratories, workshops, medical settings, and remote locations by scientists, medical personnel, medical patients, among others. 
     Generally, in the medical field, medical gas therapy includes providing high-purity gases to individuals or patients before, during, or after a medical procedure, in response to some sickness or malady, or to individuals who are otherwise in need of supplemental gases. Examples of high-purity gases used in the medical field include oxygen (O 2 ), nitrogen (N 2 ), nitrous oxide (NO 2 ), a nitrous oxide/oxygen mixture, among others. These gases are generally provided in high pressure aluminum and steel cylinders at pressures that range from 500-2200 psi. The pressurized cylinders may be of a size that facilitates transportability of the cylinder to enable easy transportation of the gas by users. The small size of the pressurized cylinders also enables use of the gas by individuals at work, in the home, and in recreational pursuits. 
     Gas control devices, such as pressure regulators, gas flow controllers, flowmeters, valve integrated pressure regulators (VIPR&#39;s), and other integrated regulator/fill/delivery devices, are typically coupled to the pressurized cylinders to facilitate delivery, filling, and general valving of the gas contained therein. The gas control device may be integral to the pressurized cylinder or may be removably coupled to the cylinder to facilitate use of the device on more than one cylinder. The gas control device and the pressurized cylinder may be generally referred to as a portable medical gas delivery system that is used by persons needing supplemental gas and/or persons in the medical field. These portable medical gas delivery systems may be further coupled to a cart or dolly having wheels or casters to enhance transportability. 
     As the portable medical gas delivery systems are highly transportable, the systems are often subject to tip-over events and the gas control device coupled thereto is subject to impacts with solid objects during use, handling, transportation, and storage. These impact events may damage the gas control device. To protect the portable medical gas delivery system from potential damage, shrouds or protective covers disposed on or around the system and/or the gas control device have been developed. 
     Conventional gas control or gas delivery devices coupled to the pressurized cylinders are generally scaled similarly to the cylinder and are typically small to minimize weight and facilitate transportability. For example, the pressurized cylinders generally include a height and a diameter, and the gas control device and/or the protective cover includes an outer dimension, which may include a perimeter or outer diameter that substantially matches the diameter of the pressurized cylinder. This scaling of the gas delivery device and/or protective cover lends an aesthetic aspect to the portable gas delivery system, and may also minimize weight and bulk of the system, which facilitates greater transportability. 
     Portable gas delivery systems are generally configured to allow a user to adjust various parameters of the gas control device to facilitate filling and/or delivery of the gas to or from the pressurized cylinder. Examples include adjustments to flow rate, velocity, volumetric adjustments, among others, either to or from the pressurized cylinder. Generally, conventional gas control or delivery devices include a coupling portion adapted to couple to the pressurized cylinder, and include at least one output valve configured to control flow rate of outgoing gas to a user. The output valve typically includes a dial or handwheel that may be accessed by a user to adjust the flow rate. 
     In one example of a conventional gas delivery device and protective cover, the handwheel to control flow rate is coupled to an upper or outer surface of the gas control device, and the handwheel typically includes characters or values indicative of a flow parameter. As this handwheel is configured to easily move in response to a desired adjustment, the handwheel is generally protected or shielded by a handle or other protective member to prevent accidental movement of the handwheel. While conventional handles or protective members may prevent undesired movement of the handwheel, access to the handwheel by the user and/or recognition of numbers or characters indicative of the flow parameter value may be limited. For example, the handle or protective member may partially cover or otherwise obstruct a view of the flow value characters. This limited view may result in an improper adjustment by a user, which may cause injury to the user. In an emergency procedure or other process where personnel are engaged to perform a double-check of flow values, the limited view of flow value characters may prevent the personnel from performing their task from a stationary position and may be required to move to a position nearer the handwheel in order to view the values. In another example, a user with a large hand or a user experiencing limited movement in the hand and/or arm by the onset of disease or injury may not be able to easily access the handwheel due to the limited area between the protective member or handle and the handwheel, which may prevent the user from performing the desired adjustment. 
     In addition, conventional protective covers are designed to minimize size and weight with little or no thought to a surface that minimizes pockets, corners, protrusions, concavities, and the like. The surfaces with pockets, corners, protrusions, concavities, and the like may trap debris and/or fluids, such as bodily fluids, that may create a biohazard if not cleaned. For example, outer surfaces with closely spaced elements and/or areas behind or adjacent elements such as the handwheel may trap fluids and debris that are accidentally impinged thereon. In order to sufficiently clean these surfaces, the protective cover and/or the gas control device may need to be disassembled, cleaned, and re-assembled prior to use. 
     Also, while conventional protective covers may allow access to some adjustment mechanisms of the gas delivery device, the protective covers may not allow sufficient access to a coupling interface of the gas delivery device configured to couple to the pressurized cylinder. As an example, the gas delivery device may be hand-tightened to the pressurized cylinder by relative rotation of one or both of the gas delivery device and the pressurized cylinder, and then a wrench or tool may be used to further tighten the hand-tight connection. Decoupling may operate inversely using the wrench or tool to loosen the gas delivery device from the pressurized cylinder. The conventional protective covers, however, may surround or otherwise limit access to the coupling interface of the gas delivery device and the protective cover may need to be at least partially disassembled to provide access to the coupling interface by the wrench or tool. 
     What is needed is a gas control device and protective cover that is ergonomically and practically designed in order to reduce difficulties encountered during coupling, adjustment, and/or refilling procedures. In addition, the protective cover should include a design that facilitates cleaning and/or minimization or elimination of areas that may trap fluids or debris. 
     SUMMARY 
     Embodiments described herein relate to a method and apparatus for providing a gas to or from a pressurized cylinder. The apparatus includes a housing that houses and protects a gas control device configured to deliver gas to a user or a device, and is configured to provide gas to a cylinder in a refilling process. The housing includes a surface free from unnecessary depressions and/or protrusions to facilitate cleanability and enhance safety during use. Adjustment indicators and status indication elements disposed in or on portions of the housing are configured to enhance readability and recognition, which facilitates safe and efficient operation of the device. Adjustable elements to control a flow metric from the gas control device are adapted to facilitate unobstructed adjustment by a user. 
     In one embodiment, a portable gas delivery apparatus is described. The apparatus includes a gas control device configured to couple to a compressed gas cylinder and comprising an integrated regulator, a fill valve and a dial for controlling gas flow through the regulator, and a multi-piece body comprising a first portion and a second portion forming substantially symmetrical halves of a housing to accommodate at least a portion of the gas control device, wherein the portions engage one another at an interface to form the housing, the interface being disposed on a longitudinal plane; wherein the first and second portions form a first opening through which the dial is disposed, the dial rotating about a central axis, and a handle sized to accommodate a human hand and disposed on an axis oriented orthogonally to the longitudinal plane and offset from the central axis; wherein the handle is supported from the body by at least one curved extension of the first portion. 
     In another embodiment, a portable gas delivery apparatus is described. The apparatus includes a gas control device coupled to a compressed gas cylinder, and a body forming a housing about at least a portion of the gas delivery device, the body comprising a first portion and a second portion forming substantially symmetrical halves of the housing, wherein the portions engage one another at an interface to form the housing, the interface being disposed on a longitudinal plane, wherein the first and second portions form a first opening through which a dial is disposed and a second opening through which a pressure gauge is disposed, wherein the dial rotates about a central axis, a handle sized to accommodate a human hand and disposed on an axis oriented orthogonally to the longitudinal plane and offset from the central axis, wherein the handle is supported a distance away from the body by at least two curved extensions of the body, and a recess formed in a lower edge of the first portion and the second portion defining a cutaway portion exposing a wrench landing formed on the gas control device. 
     In another embodiment, a portable gas delivery apparatus is described. The apparatus includes a gas control device adapted to couple to a compressed gas cylinder, and a two-piece body forming a housing about at least a portion of the gas control device, wherein the gas control device comprises a pressure gauge, a dial, and a gas outlet nipple that extends out of the two-piece body, and the two-piece body comprises a first portion and a second portion forming substantially symmetrical halves of the housing, wherein the portions engage one another at an interface to form the housing, the interface being disposed on a longitudinal plane; wherein the first and second portions form a first opening through which the dial is disposed and a second opening through which the pressure gauge is disposed, wherein the dial rotates about a central axis, wherein the dial includes a plurality of selectable settings capable of being selected by rotating the dial, the selected setting of the plurality of settings being registered with the nipple, a handle sized to accommodate a human hand and disposed on an axis oriented orthogonally to the longitudinal plane and offset from the central axis; wherein the handle is supported from the body by at least two curved extensions of the body, and a recess formed opposite the handle that exposes a wrench landing formed on the gas delivery device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a further understanding of the nature and objects of the present invention, reference should be made to the following detailed description, taken in conjunction with the accompanying drawings, in which like elements are given the same or analogous reference numbers and wherein: 
         FIG. 1  is an isometric front view of a gas delivery device housing; 
         FIG. 2  is an isometric rear view of the gas delivery device housing and body shown in  FIG. 1 ; 
         FIG. 3  is a side view of the gas delivery device housing shown in  FIGS. 1 and 2 ; 
         FIG. 4  is a cutaway side view of a gas delivery device housing and the gas control device; 
         FIG. 5  is a cutaway side view of the gas delivery device housing and the gas control device shown in  FIG. 4  that has been rotated 90°; and 
         FIG. 6  is a front view of a pressure gauge. 
     
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     Embodiments described herein relate to a gas delivery device housing to protect a gas control device disposed therein. The gas control device facilitates delivery of gas to a user or device, and may also be adapted to provide a cylinder filling capability. While the gas delivery device housing and gas control device are exemplarily shown and described for medical gas applications, embodiments described herein may be used in other applications in numerous industries and activities. Examples include laboratories, workshops, dental and veterinary applications, electronic applications, manufacturing facilities, and any other application wherein gases are delivered from a pressurized cylinder to an end use or consumer. 
       FIG. 1  is an isometric front view of a gas delivery device housing  100  configured to couple to and at least partially surround a gas control device  102  is disposed therein. The gas control device  102  may be a pressure regulator, a flow control device, a valve integrated pressure regulator (VIPR) or an integrated regulator and fill valve, and combinations thereof. In one application, the gas delivery device housing  100  is adapted to couple to a pressure vessel or cylinder  150  to provide pressurized gases, such as oxygen (O 2 ), nitrogen (N 2 ), nitrous oxide (NO 2 ), nitrous oxide/oxygen mixtures, among other gases, to the gas control device  102 . The body  105  at least partially surrounds the gas control device  102  and functions as a covering or guard to provide protection to the gas control device  102  from impact and other phenomena that may damage the gas control device  102 . The body  105  protects the gas control device  102  while also lending an ergonomic and aesthetic aspect to the gas delivery device housing  102 . While not shown, it is understood that the gas delivery device housing  100  and the cylinder  150  may be coupled to a cradle or frame to facilitate transportability. The cradle or frame may also comprise a hand-cart or dolly having wheels or casters to facilitate rolling transportation. 
     The body  105  includes a first section  106 A and a second section  106 B separated by an interface  107  where the two sections  106 A,  106 B are coupled or otherwise make contact to form the body  105 . The body  105  also includes a handle  112  formed at least partially by an extended portion  113  disposed on each of the first section  106 A and second section  106 B. The first section  106 A and the second section  106 B may be removably coupled by a plurality of fasteners (not shown), such as screws, bolts, and the like, disposed in fastening ports  114  (only one is shown in this view) formed in one or both of the first section  106 A and the second section  106 B. 
     The body  105  also includes a plurality of openings  111   N  formed in or through the first section  106 A and second section  106 B, wherein N may be any integer. Openings  111   1 ,  111   2 ,  111   3  and  111   4  are shown in this view and openings  111   1 ,  111   2 , and  111   3  are adapted to receive portions of the gas control device  102  disposed therein. For example, opening  111   1  is adapted to receive a connector  116 , opening  111   2  is adapted to receive a pressure gauge  120 , and opening  111   3  is adapted to receive a gas barb or nipple  118 . Another opening (not shown in this view) is disposed below the handwheel  110  and is configured to receive a portion of the gas control device  102 , such as a stem extending from a flow control valve integral to the gas control device  102 . One or more of the openings  111   N , such as opening  111   2  and  111   3  may include two portions  117   1  and  117   2  that are configured a substantial semicircles and form a substantially circular opening when joined at the interface  107 . Opening  111   4  may be adapted as a lightening hole to minimize the weight of the body  105 , and may comprise a curved slot. 
     The connector  116 , nipple  118 , and the pressure gauge  120  are parts associated with the gas control device  102  disposed within the body  105  and facilitate filling of a cylinder  150  and/or delivery of gas through the gas delivery device housing  100  from the cylinder  150 . The connector  116  may be an ultra high integrity service connector, such as a diameter index safety standard (DISS) connector. The nipple  118  may be an interface for a gas delivery hose, such as a hose barb, and the pressure gauge  120  is a gauge that may be configured to provide a volumetric indication of gas within the cylinder. 
     In one embodiment, each of the first section  106 A and second section  106 B are substantially symmetrical halves that at least partially surround or envelope the gas control device  102 . The extended portions  113  from each of the first section  106 A and second section  106 B may include a curve or be formed as an arc segment to provide additional space to access the handwheel  10  disposed between the extended portions  113  and below the handle  112 . In this manner, the body  105  provides an aesthetically appealing, ergonomic package to protect the gas control device  102 . Additionally, the location or configuration of the handle  112  allows users with larger hands to access to the handwheel  110 . 
     In one embodiment, the handwheel  110  includes a body  117  having multiple settings or increments indicated by values 0, ½, 1, 1½, 2, 3, 4, 6, 8, 10, 15, and 25. Each value may indicate a flow rate in liters per minute (LPM) and are positively set by rotating the handwheel  110  to a desired position. The positive setting at each value is indicated by aligning the desired value with the nipple  118  and the settings are further indicated by a “clicking” sound and/or tactile sensation. The values are large relative to the body  117  and are positioned along an annular portion  119  disposed on the body  117  of the handwheel  110 . The annular portion  119  may be angled relative the body  117  to facilitate greater readability and recognition of the values by persons other than the adjustor while also facilitating view of the values from multiple angles. The setting positions and/or the values are registered or aligned with the plane of the nipple  118  to facilitate greater accuracy and determination of the desired flow setting. 
     The gas control device  102  is capable of no-flow at 0 LPM and is configured for flow rates at ½ LPM to 15 LPM with delivery through the nipple  118 . The gas control device  102  is also adapted for a high flow rate at 25 LPM through the nipple  118 , which may be used for emergency assisted breathing procedures. A low flow rate, such as 1½ LPM or less, may be provided for specific applications, such as pediatric care, to increase patient safety and efficacy of the gas treatment. Additionally, the connector  116  may be used to provide about a 40 LPM flow rate at about 50 psi directly from the cylinder  150  in situations where a high flow rate is needed. For example, the connector  116  may be used for a temporary ventilator application providing a flow rate of about 40 LPM for about 15 minutes with a full “E” cylinder. Thus, the low flow and extended flow capabilities of the gas control device  102  enable gas delivery to a wide range of patients while also enabling patient transport capabilities for use by emergency medical technicians (EMT&#39;s). 
     The body  105  also includes a face shown as surfaces  108 A- 108 C that is substantially smooth and substantially free from obstructions, protrusions, depressions, pockets and the like that may trap debris or fluids. For example, first surface  108 A is substantially planar and meets tapered second surface  108 B adjacent the handwheel  110 , and tapered second surface  108 B slopes downward and transitions into third surface  108 C at first radius  109 A. A portion of second surface  108 B transitions to a collar  122  disposed below handwheel  110  by a second radius  109 B. Thus, the face defined at least by surfaces  108 A- 108 C and radius  109 A provides an easily cleanable surface that makes the body  105  less likely to retain any fluids impinged thereon. Surface  108 D depicts a lower portion or edge of the body  105  as is generally opposite the handle  112  and surface  108 A. 
     The face also enhances cleaning of the body  105  by minimizing obstructions that may hinder cleaning. Other portions of the body  105  and the face may also include transitioning radii into other portions, and end sections that culminate in radii to minimize sharp edges, which prevents or minimizes user injury. For example, an annular radius  445  (shown in  FIGS. 4 and 5 ) may serve to protect users during handling by eliminating any sharp breaks or edges in the body  105 , and may additionally serve as a handle to facilitate transportability of the housing  100 . Decals (not shown) may be adhered to portions of the face to identify elements of, or indicate directional operation of, the gas control device  102  and/or the gas delivery device housing  100 . For example, a decal may be adhered to tapered surface  108 B to indicate an “on” and “off” directional movement of the handwheel  110  that is aided by directional arrow decals adjacent the “on” and “off” indicator decals. Any decals that may be adhered to the gas delivery device housing  100  may comprise a fluorescent material to facilitate recognition of the decals in the dark. 
       FIG. 2  is an isometric rear view of the gas delivery device housing  100  and the body  105  shown in  FIG. 1 . Surface  108 A transitions to a sidewall of the body  105  along a radius  109 C to facilitate cleaning of the body  105  as described above. An additional fastening port  114  is shown along with additional openings  111   N , such as openings  111   4 ,  111   5 , and  111   6 , which are configured to receive portions of the gas delivery device disposed therein. As an example, opening  111   5  is adapted to receive a control valve  220  to control filling of gas through a fill port  225  disposed in opening  111   6 . Opening  111   5  may include two portions  117   1  and  117   2  that are configured as substantial semicircles and form a substantially circular opening when joined at the interface  107 . 
     The gas control device  102  includes a coupling interface  210  configured to couple to a gas cylinder (not shown in this view) by screwing or rotating into a female opening disposed in an upper portion of the cylinder. The coupling interface  210  is adapted to screw into the female opening by rotating one or both of the cylinder and the gas delivery device housing  100  relative to each other, or rotating one of the cylinder and gas delivery device housing  100  while the gas delivery device housing  100  or cylinder is held static, respectively. The coupling interface  210  is adapted to at least partially seal the connection between the gas control device  102  and the cylinder by hand-tightening, but a greater seal may be obtained by rotating the gas control device  102  with a tool or wrench subsequent to hand tightening. To facilitate access to the gas control device  102  by a wrench or tool, the body  105  includes a cutaway portion  215  forming an access area to expose a wrench landing  505  ( FIG. 5 ). Thus, the cutaway portion  215  in the body  105  facilitates access to the gas control device  102  and facilitates tightening (and loosening) of the gas delivery device housing  100  to or from the cylinder without disassembly of the body  105 . 
       FIG. 3  is a side view of the gas delivery device housing  100  shown in  FIGS. 1 and 2 . The first section  106 A is shown having three fastener ports  114  each fastener port  114  includes a fastener  314  to couple the first section  106 A to the second section  106 B (not shown in this view). Each fastener  314  may be a bolt, screw, or other fastening device or object. A first longitudinal axis or plane  300  is also shown through the housing  100 . The handle  112  is shown offset from the plane  300  in order to provide maximal access to the handwheel  110  and enhance field of view of the values located on the handwheel  110 . The offset handle  112  provides a greater area for rotating the handwheel  110 , which may allow a user having a large hand to have easier access for rotating the handwheel  110  during adjustment. Additionally, the offset handle  112  enhances visibility of the values on the handwheel  110  by not obscuring the field of view of the numbers, which may enhance adjustments to the handwheel  110  to increase efficacy and safety. An access area  315  is also shown below the cutaway portion  215  that allows access to the gas control device  102  to facilitate coupling and decoupling of the gas delivery device housing  100  to and from a cylinder (not shown). 
       FIG. 4  is a side view of a gas delivery device housing  100  that has been cutaway to show portions of the gas control device  102  disposed therein, which has also been cutaway to show interior portions of the gas control device  102 . The gas control device  102  includes a body  402  that may be made of a brass material. The body  402  also includes an inlet port  405  adapted to transfer gas to or from a cylinder  150 . The inlet port  405  is in selective fluid communication with a control valve  220 , such as a shut-off valve adapted to control release and/or filling of gas through a fill port  225  ( FIGS. 2 and 5 ). The inlet port  405  is also in selective fluid communication with a flow control valve  425  coupled to the handwheel  110  that may control a flow rate of gas to the nipple  118  and/or the connector  116  (not shown in this view). An annular radius  445  is also shown, which may be used as an alternative gripping point or handle for transporting the gas delivery device housing  100  and the cylinder  150  coupled thereto. 
     The gas control device  102  also includes a plurality of filters adapted to filter incoming or outgoing gas. In one embodiment, the gas control device  102  includes four filters, wherein three of the filters are internal to the body  402  and one of the filters is an external filter that is at least partially external to the body  402 . For example, three filters, such as filters  430   1 ,  430   2 , and  430   3  are shown in this view. Filters  430   1  and  430   2  are internal filters while filter  430   3  is external to the body  402  as the filter  430   3  extends at least partially out of the body  402 . Filter  430   1  may filter outgoing gas to the user at the nipple  118 , and filter  430   2  may filter gas before the gas enters the flow control valve  425  and/or before the gas exits the gas control device  102  when the connector  116  is used. Filter  430   3  is positioned in the inlet port  405  and may filter gas as it enters the gas control device  102  from the cylinder  150  or exits the gas control device  102  to the cylinder  150  from the fill port  225  ( FIGS. 2 and 5 ). The filters may be made of a metallic material, such as brass, bronze, a copper (Cu) material, a tin (Sn) material, alloys thereof and combinations thereof. The metallic material may be sintered and includes a porous or microporous structure that is adapted to filter micron sized particles that may be present in the gas as it enters or exits the gas control device  102 . 
     In one embodiment, filter  430   3  is configured as an insert having a portion that is received by the intake port  405  of the cylinder  150  and a portion that extends out of the intake port  405  and at least partially covers a lower surface of the coupling interface  210 . In this manner, at least a portion of the filter  430   3  extends into an opening  452  in the upper portion of cylinder  150 . The filter  430   3  may include male threads and a hex head  432  configured to be received by female threads formed in the inlet port  405  by rotational movement. The hex head  432  may be tightened to contact and extend out of the lower surface of the coupling interface  210  into the opening  452  of the cylinder  150 . 
       FIG. 5  is a side view of a gas delivery device housing  100  that has been cutaway to show portions of the gas control device  102  disposed therein, which has also been cutaway to show interior portions of the gas control device  102 . The gas delivery device housing  100  includes a second longitudinal axis or plane  500  disposed through the housing  100  at an angle orthogonal to the first plane  300  (not shown in this view). The gas delivery device  102  also includes a safety valve  540 , which includes a bursting disc  542  and a safety screw  544 , that may be used in the event the gas delivery device  102  experiences an overpressure event. A factory set pressure regulator  546  may also be disposed in the body  402 , which may control flow rate to the connector  116 . The inlet port  405  is in selective fluid communication with the fill port  225  and the connector  116 . The inlet port  405  is also in selective fluid communication with the flow control valve  425 , which is coupled to the handwheel  110  that may control a flow rate of gas to the nipple  118  (not shown in this view). The inlet port  405  may also be in selective fluid communication with the connector  116 . A filter  4304  may be disposed in an inlet portion of the fill port  225  to filter incoming gas to the gas control device  102 . The fill port  225  and the connector  116  may also include caps  516  to protect threading formed thereon. 
     As described above, an access area  315  is formed in the gas delivery device housing  100 . The access area  315  is adapted to expose a portion of the gas delivery device  102  to facilitate coupling and decoupling of the gas delivery device housing  100  and the cylinder (not shown in this view). The access area  315  exposes a wrench landing  505  formed on the body  402  of the gas control device  102 . The wrench landing  505  may be flatted portions of the body  402  and is adapted to receive a wrench or tool (not shown) to tighten and loosen the gas delivery device housing  100  relative to the cylinder. Thus, the access area  315  provides ingress and egress to the gas control device  102  without disassembly of the gas delivery device housing  100 . 
     The body  105  of the gas delivery device housing  100  may also include concave or dished sidewalls  518  adjacent an opening  111   N . As shown in this Figure, openings  111   1  and  111   6  include a dished sidewall  518  that transitions inward from an outer surface of the body  105 . The dished sidewall  518  is adapted to decrease the size of the gas delivery device  102  by admitting the connector  116  and fill port  225  in closer proximity to the body  402  while enhancing access to these connection points. The dished sidewalls  518  may also include a smooth surface that is free of pockets and protrusions in order to enhance cleaning and cleanliness of the body  105 . 
       FIG. 6  is a front view of a pressure gauge  120  that may be coupled to the gas control device  102 . The pressure gauge  120  includes a face  610  having an arcuate indicator band  620 , a pointer  615 , and a content indicator, which is depicted as O 2  in this example. The pressure gauge  120  is adapted to facilitate a volumetric indication of gas within the cylinder as the gas delivery device is coupled thereto. The pressure gauge  120  is also adapted to facilitate enhanced readability and recognition of the volumetric indication in a “gas gauge” or “fuel gauge” style that may be used in the vehicle industry. For example, the indicator band  620  includes relatively large values indicating a “0” capacity to a “FULL” capacity with incremental values of ¼, ½, and ¾ therebetween. The “fuel gauge” style is used in combination with standard psi values to facilitate recognition of the volumetric indication for users who are sight challenged and/or users who are not familiar with or comfortable reading the psi values. The indicator band  620  may also include regions  632 ,  634 , and  636  that may be shaded or hatched, or include a color scheme to facilitate readability of the pressure gauge  120 . For example, regions  632  and  636  may be colored red to indicate a low or near low volume of gas contained in the cylinder, while region  634  may include a green color to indicate a full or near full capacity. The color scheme enhances readability and recognition of capacity without the need to discern specific values and may also serve to alert a user to a near low capacity and prompt a fill or cylinder replacement. Region  636  may also include hatched lines  638  in combination with a color schema. 
     An improved gas delivery device housing has been described. The gas delivery device housing  100  houses and protects a gas control device that facilitates delivery of gas to a user or device, and may also be adapted to provide a cylinder filling capability. The housing  100  includes a surface free from unnecessary depressions and/or protrusions to facilitate cleanability and enhance safety. Adjustment indicators and status indication elements disposed in or on portions of the housing  100  are configured to enhance readability and recognition, which facilitates safe and efficient operation. Adjustable elements to control a flow metric from the gas control device are adapted to facilitate adjustment by a user with a large hand or a user suffering from some diminished physical capability. 
     It will be understood that many additional changes in the details, materials, steps, and arrangement of parts, which have been herein described and illustrated in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims. Thus, the present invention is not intended to be limited to the specific embodiments in the examples given above and/or the attached drawings.