Element for controlling filling and/or drawing of a pressurized gas, tank and circuit provided with such an element

The invention relates to an element for controlling filling and/or drawing of a pressurized gas, to be mounted in an opening of a tank (1), comprising a body (21) provided with at least one device (8) for controlling the circulation of gas placed between a first end, which has an opening (31) forming an inlet and/or an outlet for the gas with regard to the tank, and a second end for communicating with the inside of the tank. The control element also comprises a safety gas escape device (5) for evacuating the gas from the reservoir in the event of a dangerous situation and comprises a channel or gas escape circuit (215, 213, 212, 211, 31) running between a first end (215) for communicating with the pressurized gas of the tank and a second end (31) for communicating with a user circuit or with the atmosphere, the escape circuit being closed or not according to the state of a safety element (52), characterized in that the second end of the gas escape circuit (215, 213, 212, 211, 31) coincides with the opening (31) of the control element forming an inlet and/or an outlet for the gas.

This application is a 371 of International PCT Application PCT/FR2006/051053, filed Oct. 18, 2006.

BACKGROUND

1. Field of the Invention

The present invention relates to a member for controlling filling and/or drawing of a pressurized gas and to a tank and a circuit which are provided with such a member.

2. Related Art

Among known solutions for storage in gaseous form, bottles equipped with a simple tap are very favorable to operators and manufacturers for stock management purposes. If it is open, the simple tap puts the user directly into contact with the fluid at its storage pressure. In order to use the gas, it is thus necessary to connect various equipment (regulator, flowmeter, etc.) that requires tools and tedious operations. This type of operation entails risks especially when the user is not professional. This solution is thus not favorable to the end user.

More favorable to the end user is the regulator tap attached to the bottle and delivering the fluid at the pressure needed for the application. However, operating with such a tap involves significant constraints for manufacturers particularly in terms of stock management, maintenance and interface with the filling equipment.

Hence, none of the aforementioned existing solutions simultaneously takes account of the specific needs of the manufacturer and the customer.

Moreover, particularly in the field of storing combustible gases used as energy source on board vehicles (such as, for example, hydrogen for fuel cell vehicles or internal combustion engine vehicles), the normative and regulatory references or the safety rules demand the presence of a pressure-limiting safety member (pressure relief valve or PRD) which, in the event of fire, allows the complete evacuation of the gas contained in the tanks to the atmosphere, thus preventing these tanks from bursting.

In one configuration of a fixed tank on board a user system (for example a vehicle), the safety members are defined and consequently positioned permanently thereon. However, the problem is more complicated for gas storage devices intended to be placed on board following the “replacement of an empty tank by a full tank” principle. This is because, in the case of mobile containers, the safety member must follow the container throughout its life cycle (both outside and inside the user system).

The double life of these gas storage devices (on the one hand used as onboard tanks and on the other hand transported or stored under pressure during logistics phases) requires that the safety members have different behaviors according to the use phase.

The size, mass, structural simplicity and ease of use of these tanks and their control members are crucial factors for their large-scale use in a gas supply system of the “replacement of an empty tank by a full tank” type.

Conventional bottles equipped with a simple tap do not generally have a safety valve or limiter of the PRD type. In order to use the gas, it is thus necessary to connect the bottle to an onboard installation having at least one safety member of this type. The installation must also comprise a regulator. This increases the risks during use, especially when the user is not professional (leaks, projection of parts, etc.).

The invention thus aims to solve all or some of the aforementioned problems so as to provide, for example, a level of safety and efficiency in the storage and use of pressurized gas that satisfies all or some of the use constraints above and allows handling operations especially by non-specialists.

SUMMARY OF THE INVENTION

The invention thus relates to a member for controlling filling and/or drawing of a pressurized gas that is intended to be mounted in an orifice of a tank, comprising a body provided with at least one gas flow control device arranged between a first end, comprising an orifice forming an inlet and/or an outlet for the gas with respect to the tank, and a second end intended to communicate with the inside of the tank, the control member additionally comprising a gas escape safety device for evacuating the gas from the tank in the event of a risk situation and comprising a gas escape channel or circuit extending between a first end, intended to communicate with the pressurized gas of the tank, and a second end intended to communicate with a user circuit or with the atmosphere, the escape circuit being either shut off or not depending on the state of a safety element.

According to one advantageous particular feature, the second end of the gas escape circuit coincides with the control member orifice forming an inlet and/or an outlet for the gas.

DETAILED DESCRIPTION OF THE INVENTION

Moreover, embodiments of the invention may comprise one or more of the following characteristics:the second end of the gas escape circuit coincides with a control member inlet/outlet orifice intended both to let gas in (filling) and to let gas out (drawing);the member comprises an expansion portion accommodating a pre-expansion device, the control member additionally comprising a mounting portion intended to be mounted in the orifice of a tank, the expansion portion and the mounting portion being arranged relatively on the body in such a way as to arrange the expansion portion at least partially inside the volume of a tank when the member is in the mounted position;the safety element and the expansion portion are respectively arranged substantially on either side of the mounting portion in such a way as to arrange the safety element at least partially outside a volume of a tank when the member is in the mounted position;the safety device comprises a shut-off element capable of being moved between a position in which it shuts off the gas escape circuits and a position in which it does not obstruct this circuit, the safety element forming a retractable stop for retaining the shut-off element in the shut-off position;the member comprises a filling channel or circuit for the pressurized gas that extends between a first end, intended to be connected to a pressurized filling gas source, and a second end intended to communicate with a tank, a filling valve device being arranged on the filling circuit, the filling valve being dimensioned to open only above a threshold pressure so as to allow pressurized gas to flow between the two ends of the filling circuit only in a filling direction and when the pressure of the filling gas exceeds said threshold;the filling valve is able to move relative to a seat secured to a frame, the element for shutting off the escape channel comprising said frame;the filling and escape circuits comprise at least one common portion;the member comprises a gas drawing circuit extending between a first end, intended to be connected in the mounted position with the inside of the tank, and a second end intended to be connected to a user circuit which uses the gas drawn from the tank;the member comprises, arranged in the drawing circuit and in addition to a pre-expansion device, at least one of the control elements from the following group: a gas filtering element, a device forming a residual pressure valve, and an isolating valve;the member comprises, arranged in series in the drawing circuit between the first and the second end: a gas filtering element, a device forming a residual pressure valve, the pre-expansion device and an isolating valve;the drawing circuit is substantially rectilinear between its two ends;the member comprises a high-pressure discharge valve having a first end, intended to be connected with the pressurized gas in the mounted position, and a second end connected to an outlet for evacuating fluid when the pressure exceeds a defined value above a threshold;the safety element comprises at least one of the safety elements from the following group: a thermal fuse, a rupture disk, a discharge valve, and a valve controlled as a function of a measured pressure and/or temperature;the safety element of the safety device (for example a thermal fuse) comprises or constitutes the high-pressure discharge valve,the safety element comprises a spring urging the shut-off element toward its shut-off position, the preload force of which spring is greater than the force caused by the pressure of the fluid stored under normal use conditions (that is to say outside an overpressure risk situation);that portion of the escape circuit situated between the shut-off element and the first end comprises a channel formed in the body of the member and capable of bringing the shut-off element directly into communication with the pressurized gas in the reservoir in the mounted position;in the mounted position, the shut-off element is urged by the pressurized gas toward its non-shut-off position;the escape and drawing circuits are separate and substantially parallel over at least some of their length;the exhaust and drawing circuits have a common portion at least at the level of the inlet/outlet orifice of the member;the filling and escape circuits are common, that is to say that the gas follows substantially the same circuit, in opposite directions, while being filled and while escaping for safety reasons;the control member has a substantially oblong and cylindrical shape;the control member comprises a device for measuring a physical variable such as the pressure representative of the contents, this device being able to be connected directly to the pressurized gas in the mounted position and being able to cooperate with means for displaying said physical variable that are situated on the control member and/or remotely;the mounting portion of the filling control member is substantially cylindrical or conical and comprises at least one fastening element such as threads which are intended to cooperate with a complementary surface such as a tapped thread on a container neck;the mounting portion of the control member comprises an element intended to ensure leaktightness with the container during a tightening operation, such as a Teflon® layer;the isolating valve is housed inside the volume of the control member and comprises an end accessible via an inlet/outlet orifice provided with a retractable shutter, the isolating valve being able to be moved between a position of opening and a position of closing the drawing circuit under the action of a complementary end of a user apparatus introduced into the body of the control member via the inlet/outlet orifice;the body of the control member comprises a portion forming a connection interface for a user circuit or apparatus which uses the gas passing via the control member, the portion forming a connection interface and the expansion portion being respectively arranged substantially on either side of the mounting portion in such a way as to arrange the portion forming a connection interface at least partially outside the volume of the tank when the member is in the mounted position;the invention may also relate to a vehicle comprising a control member or a control member/container assembly according to any one of the characteristics above;the gas is hydrogen or contains hydrogen.

Another object of the invention is to provide a pressurized gas container comprising an orifice and a filling and/or drawing control member according to any one of the characteristics above.

Another object of the invention is to provide a pressurized gas use circuit which comprises a container connected to the use circuit via the control member, the circuit being connected to the inlet/outlet orifice of the control member, the circuit comprising a mechanism forming a high-pressure safety valve capable of evacuating the pressurized escape gas toward the atmosphere or into a defined safeguarded region.

According to other particular features, the circuit comprises a main line connected to a gas user and an auxiliary safety line connected to the main line, the mechanism forming a high-pressure safety valve being situated in the main line and/or in the auxiliary line.

The non-limiting embodiment shown inFIG. 1depicts the oblong body of a gas tank1having a cylindrical main central part10and two dome-shaped ends11and12. The tank1is preferably made of composite materials, for example an aluminum alloy liner reinforced by a filament winding of carbon fibers bound together by epoxy resin.

One rounded end12of the tank1comprises an inlet/outlet orifice for the fluid, in which orifice is mounted a member2for controlling filling and/or drawing of the gas. In the mounted position on the tank1, a first portion of the control member2is situated inside the volume of the tank1and a second portion projects outside the tank1. The control member2comprises in its external portion a connection interface3intended to cooperate by latching with complementary latching parts borne, for example, by a user apparatus, a circuit or a device for filling the tank1.

Moreover, the control member2comprises, in its part situated outside the tank1, an indicator4showing the state of the contents, such as a pressure gauge, and a gas escape safety device5described in more detail below.

The external end of the control member2is provided with a central orifice31designed to give access to the inside of the tank1.

FIG. 2depicts the control member2away from the storage tank1. This control member2is composed of an oblong body21of generally cylindrical shape substantially comprising, in its central part, a threaded conical coupling24intended for the leaktight fastening of said member2in the orifice of the storage tank1.

In the mounted position on a tank1, a first part22of the volume of the control member is thus situated inside the tank1while a second part23of the volume of the member2is situated outside the tank1, thus offering access to the connection interface3, to the indicator4showing the state of the contents, to the safety device5, and to the central orifice31which allows gas to be filled and/or drawn.

Referring toFIG. 3, the body21of the control member2is joined mechanically to the tank1by means of the conical screw thread24cooperating with a tapped thread formed in the neck of the tank1. Leaktightness between the member2and the tank1can be maintained, for example, particularly using a Teflon strip applied to the threads.

The control member2incorporates within its volume, substantially at the level of its first end, from upstream to downstream: a member6for filtering the drawn gas, a residual pressure valve7permanently maintaining a minimum pressure (for example about 3 bar) of gas in the tank1to prevent its contamination, a pre-expansion member8allowing the gas to leave at a defined pressure close to the pressure needed for the application, and an isolating valve9making it possible to allow or interrupt the drawing of the gas. As represented inFIG. 3, part of the pre-expansion member8can project from the first end of the body21of the control member2, the residual pressure valve7and the member6for filtering the drawn gas being mounted on this projecting part of the pre-expansion member8.

The connection interface3is embodied by four protruding studs32(or bayonets) which allow couplings having complementary imprints to be latched on in order to fill the tank1with gas or draw the gas contained therein. The central orifice31of the gas filling and/or drawing control member2can be protected from external particles by means of a movable shutter33. The movable shutter33has, for example, the form of a pin which is subjected to the action of a return spring34toward a closure or rest position of the orifice31in which the end surface331of said shutter33coincides with the front surface351of a cannula35of the connection interface3. The cannula35is partly housed in the body21of the control member2.

As represented in an enlarged manner inFIG. 8, the pre-expansion member8can be contained within a pre-expansion cartridge122screwed into the body24of the control member2via a screw thread/tapped thread system221.

Upstream of the pre-expansion member8, the control member2comprises a filter6followed by a residual pressure valve7known per se. Such a residual pressure valve operates schematically in the following way: the spring71acts on the valve element72and tends to naturally seal the residual pressure valve element72on its seat73. As long as the force of the gas pressure on the cross section of the valve element72is greater than the force of the spring71, the valve allows fluid to flow. The residual pressure valve element72closes the circuit when the force of the gas pressure on the cross section of said valve element72is insufficient to overcome the force of the spring71. This level of pressure (above atmospheric pressure, for example of around 3 bar) is that which will remain inside the tank at the end of the use phase in order to prevent various contaminations. This residual pressure valve7allows fluid to flow, for example, only in the direction of gas outflow toward the outside (in the direction of the orifice31) and only when the pressure of the gas is above a threshold permitting opening of this valve7(for example 3 bar). The filter6and the residual pressure valve7are, for example, housed in a casing267screwed onto the upstream end of the pre-expansion cartridge122.

Downstream of the pre-expansion member8(toward the outlet31), the control member2comprises a low-pressure chamber223. Leaktightness between the inside of the tank1and the low-pressure chamber223is ensured, for example, by the combination222of an O-ring seal and anti-extrusion rings arranged between the cartridge122and the body24of the control member2. The filter6is retained in the cartridge22for example by means of a spring ring241housed in a groove223formed in the casing267.

The valve element26of the pre-expansion member8is subjected to the action of a spring261toward a seat27retained in the cartridge122under the action of a threaded seat holder271. The valve element26is subjected to the force of the valve spring261and to the force of the pressurized gas.

The downstream end of the valve element26is provided with a stem1261whose end is in contact with a pre-expansion piston28. This piston28is subjected for its part to a stress exerted by a spring281in the direction of the pre-expansion valve element26. Owing to the force of the spring281and the action of the gas on the downstream cross section of the piston28, the valve element26performs a pressure-regulating function.

During phases in which gas is drawn from the tank1, the gas contained in the tank1under high pressure passes via the filter6and then expands in the cartridge122toward the low-pressure chamber223.

The expanded gas then passes through the piston28by way of a bore283formed in the body of the piston26so as to emerge in a chamber232situated upstream of the isolating valve9. The isolating valve9ensures leaktightness between the body21and the inside of the tank1by means of seal systems or the like.

The isolating valve9is closed by default. The isolating valve9is, for example, a valve of conventional type, such as a valve comprising a fixed tubular body and a spindle which can move inside the body and make the valve capable of allowing fluid to flow or not depending on the position of the spindle.

The valve9can be actuated via a valve pusher belonging, for example, to a storage assembly user system or to a gas distribution head.

According to the embodiment inFIG. 4, the end of a filling adapter100is coupled to the external end of the control member2. More precisely, the filling adapter100has a body101and a connection interface comprising imprints103which are able to cooperate with the protruding studs32of the connection interface3of the control member2.

The connection interface of the filling adapter100comprises a pin or spigot104dimensioned to be housed in the central well357of the cannula35. Thus, when the connection interface of the filling adapter100is engaged and cooperates with the connection interface3of the member2, the pin104is housed coaxially in the well357of the cannula35. Furthermore, the end105of the pin104of the filling adapter100comes into contact with the downstream surface331of the shutter33, pushing this shutter away while combating the force of the spring34.

When the connection interface of the filling adapter100is in the final position on the connection interface3of the member2, the front outer peripheral surface of the pin104is in contact with a first sealing device352comprising, for example, a seal and an anti-extrusion ring, whereas a rear outer portion of the pin104is in contact with a second sealing device comprising a seal and an anti-extrusion ring353. Between these two portions, the peripheral surface of the pin forms a leaktight annular chamber358(local constriction of the pin104for example) between the pin104and the cannula35of the control member2.

During an operation of filling the tank1, the filling fluid is drained through the filling adapter100via a central duct102which emerges in the annular chamber358. For example, the central duct102which emerges in the annular chamber358by way of radial orifices106formed through the central part of the pin104.

The filling fluid then passes through the cannula35via holes or ducts356so as to arrive in an annular chamber211formed between the body21and the cannula35. Leaktightness of the chamber211is ensured via, for example, two sealing assemblies354,355each comprising for example a seal and an anti-extrusion ring. The annular chamber211then drains the filling fluid toward a bore212which emerges in an annular chamber213of the safety device5.

FIG. 5shows in more detail the safety device5housed in the body of the filling and/or drawing control member2. As represented, the safety device5can be contained within a volume projecting transversely from the oblong body of the control member2.

The safety device5comprises a cartridge body53or frame which encloses a valve element56. The valve element56is naturally maintained, in a position in which it shuts off the flow of fluid in a leaktight manner, against a seat55under the action of a spring57. The seat55, which is preferably not made of metal, is centered and maintained in a leaktight manner relative to the body by means of a seat holder54screwed, for example, into the cartridge body53.

A plug51having a fusible spacer52(such as a eutectic alloy with a low melting point, for example a bismuth-indium alloy) encloses the cartridge53in a well of the body21of the member2. The plug51is, for example, screwed into the end of the well of the body21of the control member2.

To ensure particularly effective heat transfer between the ambient environment and the fusible spacer52, the plug51preferably has a high thermal conductivity; it consists, for example, of a copper alloy. Moreover, grooves219can be formed in the body21to increase the heat-exchange area with the ambient environment in the region where the fuse52is situated.

The filling fluid entering the annular chamber213, which is leaktight between the cartridge53and the body21(seals and anti-extrusion rings531and532), successively passes through the cartridge53via first lateral orifices533and then passes through the seat holder54via the second bores543. The fluid then follows the central duct542of the seat holder54which emerges at the level of the valve element56.

The valve element56opens under the force of a defined pressure of the filling fluid (above a defined threshold pressure to prevent contamination of the contents of the tank1). The opening of the valve element56allows the fluid to pass into an intermediate chamber534.

Countersinks581of a spacer58then drain the fluid into a downstream chamber214. A bore215communicating on the one hand with the downstream chamber214and on the other hand with the inside of the tank1allows the fluid to be conveyed inside the tank.FIG. 9schematically illustrates the bore215which emerges at the level of a shoulder delimiting the end of the threaded mounting portion24of the body21(the bore215emerges at the level of a portion situated in the tank1when the control member2is in the mounted position).

When the filling operation is completed and the filling circuit has optionally been purged, the valve element56automatically returns to its leaktight closure position on its seat55under the action of its spring and isolates the inside of the tank1. The filling adapter can be withdrawn, the movable shutter33of the connection interface3then automatically returning to its rest position under the action of the spring34.

InFIG. 6, the gas filling and/or drawing control member2is connected to an output coupling900composed of a body901having a connection interface comprising imprints903cooperating with the protruding studs32of the connection interface3.

When the connection interface of the outlet coupling900is engaged and cooperates with the connection interface3of the control member2, the pin904of the outlet coupling900is housed coaxially in the well357of the cannula35. The end905of the pin904of the outlet coupling900comes into contact with the surface331of the shutter33. The pin904pushes away the shutter33while combating the force of the spring34until it opens the isolating valve9as a result of the contact of the stem332of the shutter33against the pin of the valve9.

When the connection interface of the outlet coupling900is in the final position on the connection interface3of the member2, the rear outer peripheral surface of the pin904is in contact with the downstream sealing assembly353comprising a seal and an anti-extrusion ring. In this way, the pin904is housed in a leaktight manner in the cannula35with respect to the outside.

The fluid drawn from the tank1, once it has passed into the filtering member6, then into the residual pressure valve7and into the pre-expansion member8, passes through the isolating valve9. The fluid then arrives in the chamber358containing the shutter33and then follows the milled-out aperture908to arrive in the central duct902of the outlet coupling900(through the pin904to be outwardly distributed into a network toward a user).

As represented inFIG. 7, an overheating (due for example to a fire) activates the safety member5by causing the fuse52to melt, this fuse being evacuated for example through an orifice511of the plug51. The force of the high pressure of the fluid contained in the tank1that is applied to the cross section of the cartridge53then makes it possible for the cartridge53to be moved until it butts against the surface512of the plug51.

The cartridge becomes positioned in a portion of the well of the body21in which the sealing elements no longer cooperate against the body21. In other words, the combination532of a seal and anti-extrusion rings then loses its leaktightness function and brings the chamber214into communication with the annular chamber213. In this way, the escape channel is open for the high-pressure fluid coming from the inside of the tank via the orifice215. From the annular chamber213, the fluid is evacuated toward the outside through the bore212.

The gas can be evacuated differently depending on whether the tank1is or is not connected to a user circuit.

If the tank1is connected to its outlet coupling900by its control member2(cf.FIG. 6), the fluid passing through the bore212arrives in the annular chamber211of the body and then passes through the bores356of the cannula35so as to be situated in the annular chamber359formed between the pin904and the cannula35. This chamber359formed between the pin904and the cannula35communicates with the upstream chamber358containing the shutter33. This communication is made possible by the geometry of the end of the pin904(diameter in particular), providing a clearance between the pin904and the sealing system352(seal and anti-extrusion ring).

From the chamber358, the fluid is evacuated toward the central duct902of the outlet coupling900via the milled-out aperture908machined into the pin904. The duct902emerges into a network of the application comprising, for example, a main line100and an auxiliary safety line101connected to the main line100. The auxiliary line101comprises a mechanism950forming a high-pressure safety valve designed to evacuate the pressurized gas toward the atmosphere in a defined region when the pressure of the gas exceeds a limit value.

Thus, the high-pressure fluid which escapes from the tank in the event of overheating is evacuated by the safety valve950which, by virtue of an evacuation conduit or the like, leads the fluid to the atmosphere in a known and controlled region of, for example, a vehicle.

If, on the other hand, the full tank1is not connected, for example if it is at rest in a storage phase (cf.FIG. 3), the fluid coming from the tank and passing through the bore212arrives in the annular chamber211and then passes through the bores356of the cannula35so as to be situated in the annular chamber339.

The clearance provided between the shutter33and the cannula35then allows evacuation of the high-pressure fluid drained toward the atmosphere via the orifice31.

The gas filling and/or drawing control system according to the invention thus allows:the fluid to be admitted, via the filling circuit, to the inside of a tank during container filling phases, this taking place when the filling pressure is above a threshold pressure defined to prevent contamination of the container and the contents,the fluid contained under high pressure in the container to be isolated from the ambient air (nonreturn function of the valve element56in particular),in the event of a rise in temperature due, for example, to a fire, the fluid contained under high pressure in the container to be evacuated out of the container.

The safety evacuation or escape can take place:via the orifice31of the connection interface when the container is not connected (for example transported or stored during logistics phases),via the safety circuit of a supply network when the container is connected (for example a network of a fuel cell or of a vehicle).

The outflow of the escape gas (in the event of overpressure) occurs via the orifice (preferably a single orifice) which serves equally for filling and drawing. Thus, the gas uses one and the same orifice for filling/drawing/escaping in the event of overpressure. This allows a single connection to the tank and hence simplifies the operations for a user. The gas evacuated in the event of overpressure in the tank can thus be collected through this orifice toward a user circuit, toward a safeguarded region. This characteristic is particularly advantageous when the gas is at risk, such as hydrogen.

Of course, the invention is not limited to the exemplary embodiment described above. Thus, for example, the safety device could comprise a high-pressure discharge valve designed to evacuate the fluid toward the outside when the pressure inside the container1exceeds a defined value above a threshold, the threshold being greater than the storage pressure.

Advantageously, the high-pressure discharge valve function can be performed by the fusible spacer52of the safety member5. For example, the fusible spacer52could consist of a spring which is able to convert the safety device into a high-pressure discharge valve by allowing the plug53(or cartridge) to move under certain pressure conditions. In that case, the force provided by the spring on the cartridge53must be greater than the force produced by the pressure of the filling fluid.

In a variant, it would likewise be possible for a spring to be inserted between the fusible spacer52and the cartridge53of the safety device5such that said safety device5evacuates the fluid contained in the tank in the event of a rise in the ambient temperature and/or in the event of an overpressure of the fluid contained in the tank.

In a variant, the shutter33may be produced from a fusible material (eutectic alloy with a low melting point, for example a bismuth-indium alloy) so as to melt at the same time in the event of overheating and thus allow a greater gas flow at the level of the central orifice31.

Furthermore, the thermal fuse may be replaced by any other safety element, for example: a rupture disk, a discharge valve, or a valve controlled as a function of a measured temperature and/or pressure.

The invention can thus be used in all applications requiring a high ease of use and a good compromise between lightness of weight, size and capacity (autonomy). By way of non-limiting example, the invention is applicable to gaseous hydrogen for a portable or mobile fuel cell, to medical gases and to gases for analysis purposes and laboratories.