System for hydrogen leak detection in a hydrogen compression machine and associated method
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- HIPERBARIC
- Filing Date
- 2025-11-21
- Publication Date
- 2026-08-06
Smart Images
Figure ES2025070720_06082026_PF_FP_ABST
Abstract
Description
[0001] HYDROGEN LEAK DETECTION SYSTEM IN A HYDROGEN COMPRESSION MACHINE AND ASSOCIATED PROCEDURE DESCRIPTION OBJECT OF THE INVENTION
[0002] The present invention relates to a hydrogen leak detection system in a hydrogen compression machine and the associated procedure.
[0003] The hydrogen leak detection system in a hydrogen compression machine of the present invention allows the detection of possible leaks through the piston seals and coming from the hydrogen chamber side within the atmospheric chamber in each of the pressure multiplier stages, at the same time, efficiently directing the hydrogen to the outside as quickly as possible, thus minimizing the risk of an increase in hydrogen concentration inside the compressor container, thereby increasing its safety.
[0004] BACKGROUND OF THE INVENTION
[0005] Hydrogen compression technology is a technique that allows compression up to 1,000 bar to compress gas for storage, or for use in hydrogen refueling stations, where it allows filling 50-1001 tanks of vehicles with several kg of H2 at pressures of 350 bar (trucks, buses, ...) and 700 bar (new vehicles with latest generation fuel cell).
[0006] One of the major challenges in compressing hydrogen (H2) is that, due to the small size of its molecules, it is very difficult to contain and, in contact with oxygen in a confined space, can result in a highly explosive mixture. Therefore, it is vitally important to keep leakage rates under strict control and ensure the rapid evacuation of the gas from such confined spaces.
[0007] One of these critical areas is the atmospheric chamber, located within the pressure multiplier. There are two chambers per pressure multiplier, one for each compressor stage. This chamber is enclosed between the rear face of the piston and the inner walls of the cylinder liner and spacer vessel. The hydrogen leak detection system in a hydrogen compression machine of the present invention overcomes all the aforementioned drawbacks.
[0008] DESCRIPTION OF THE INVENTION
[0009] The present invention relates to a hydrogen leak detection system in a hydrogen compression machine that effectively detects leaks from the sealed hydrogen chamber into the atmospheric chamber separating the hydrogen chamber from the hydraulic chamber. This system aims to prevent a dangerous increase in hydrogen concentration, reaching a lower explosive limit (%LI E) considered unacceptable, and also prevents this concentration increase from occurring inside the compressor container itself by directing it through vent pipes to an extraction chimney.
[0010] The hydrogen leak detection system in a hydrogen compression machine, where the hydrogen compression machine comprises:
[0011] - at least one pressure multiplier, which in turn comprises:
[0012] - at least one rod connectable at a first end to a first piston displaceable inside a first sleeve arranged adjacent to a first spacer vessel and connectable at a second end to a second piston displaceable inside a second sleeve arranged adjacent to a second spacer vessel, wherein the volume arranged between a rear face of the first piston, and the first sleeve and the first spacer vessel defines a first atmospheric chamber, and wherein the volume arranged between a rear face of the second piston, and the second sleeve and the second spacer vessel defines a second atmospheric chamber, and
[0013] - at least a first sealing system arranged on the first piston, and - at least a second sealing system arranged on the second piston; wherein the hydrogen leak detection system comprises:
[0014] - a first vent duct connecting the first atmospheric chamber with at least one hydrogen sensor configured to detect the concentration of hydrogen in air, inert gas, or a mixture of both, in the first atmospheric chamber;
[0015] - a second vent pipe connecting the second atmospheric chamber to at least one hydrogen sensor configured to detect the concentration of hydrogen in air, inert gas or a mixture of both, in the second atmospheric chamber; - a control unit configured to determine whether the concentration of hydrogen in air, inert gas or a mixture of both, coming from the first atmospheric chamber and / or the second atmospheric chamber is above a first threshold value, and consequently, determine whether the at least one first sealing system arranged on the first piston and / or the at least one second sealing system arranged on the second piston must be replaced.
[0016] Thus configured, the hydrogen leak detection system of the present invention allows the detection of possible leaks through the first sealing system or the second sealing system and which come from the side of the hydrogen chamber within the atmospheric chamber in each of the stages of the multipliers, and at the same time, efficiently directs this gas to the outside as quickly as possible, thus minimizing the risk of an increase in the concentration of H2 inside the hydrogen compression machine, increasing its safety, since a value of the H2 concentration above the threshold value indicates that the level of explosiveness is outside the safety limits.
[0017] Optionally, at least one rod attachable at the first end to the first piston displaced inside the first sleeve arranged adjacent to the first spacer cup and attachable at a second end to a second piston displaced inside a second sleeve arranged adjacent to a second spacer cup, is fixed to the first piston displaced and the second piston displaced.
[0018] Optionally, the at least one stem, attachable at the first end to the first piston displaced inside the first sleeve arranged adjacent to the first spacer cup and attachable at a second end to a second piston displaced inside a second sleeve arranged adjacent to a second spacer cup, is, in use, in contact with the first and second pistons.
[0019] Optionally, the hydrogen leak detection system comprises a first hydrogen sensor communicated with the first atmospheric chamber via the first vent duct and configured to detect the hydrogen concentration in air, inert gas, or a mixture of both, in said first atmospheric chamber, and a second hydrogen sensor communicated with the second atmospheric chamber via the second vent duct and configured to detect the hydrogen concentration in air, inert gas, or a mixture of both, in said second atmospheric chamber.
[0020] In this way, and given that the density of hydrogen is less than that of air, inert gas or a mixture of both, hydrogen will always flow upwards, hence the at least one hydrogen sensor is located upstream of the first vent pipe and the second vent pipe.
[0021] Optionally, the distance between at least one hydrogen sensor and the first vent pipe and / or the second vent pipe is in the range between 0 and 500mm, in order to ensure the homogenization of the air, inert gas or mixture of both-hydrogen.
[0022] Optionally, the first vent duct and / or the second vent duct have a smaller cross-section than the first atmospheric chamber and / or the second atmospheric chamber respectively, preventing residual air, inert gas, or a mixture of both from remaining inside, even at atmospheric pressure. This is because the cross-section of the first vent duct and / or the second vent duct, along with their length, results in a higher pressure drop for the air, inert gas, or mixture of both circulating through them.
[0023] Optionally, the internal volume of the first vent duct and / or the second vent duct is at least 50% less than the internal volume of the first atmospheric chamber and / or the second atmospheric chamber, respectively, preferably 75% less, more preferably 85% less, ensuring the renewal of air, inert gas or mixture of both in each stroke and that therefore there is residual air, inert gas or mixture of both, housed inside even at atmospheric pressure.
[0024] Optionally, the hydrogen leak detection system comprises a set of baffles arranged between the first and / or second vent ducts and the at least one hydrogen sensor. These baffles are configured to guide the air, inert gas, or a mixture of both with the hydrogen and to protect the vent duct outlet from the entry of dirt and / or particles, as well as to protect the at least one hydrogen sensor from the direct impact of the air, inert gas, or mixture of both with hydrogen, which could generate erroneous readings. Preferably, the baffle assembly is labyrinth-shaped. Also preferably, the baffle assembly is grid-shaped.Optionally, at least one hydrogen sensor is positioned above at least one pressure multiplier, since the density of hydrogen is less than that of air, inert gas, or a mixture of both, and hydrogen will always flow upwards.
[0025] Optionally, the pressure multiplier comprises at least one air, inert gas, or mixture of both inlet disposed in the first atmospheric chamber and at least one air, inert gas, or mixture of both outlet disposed in the second atmospheric chamber, or vice versa, wherein the air, inert gas, or mixture of both entering through the at least one air inlet is ambient air or inert gas or mixture of both, which is mixed in the first atmospheric chamber or in the second atmospheric chamber with the hydrogen escaping through the at least one first sealing system or the at least one second sealing system, respectively, and wherein the air, inert gas, or mixture of both exiting through the at least one air, inert gas, or mixture outlet has a hydrogen concentration that is evaluated in the at least one hydrogen sensor.
[0026] The invention also relates to a hydrogen compression machine comprising: - at least one pressure multiplier, which in turn comprises:
[0027] - at least one rod connectable at a first end to a first piston movable inside a first sleeve arranged adjacent to a first spacer vessel, wherein the at least one rod is connectable at a second end to a second piston movable inside a second sleeve arranged adjacent to a second spacer vessel, wherein the volume arranged between a rear face of the first piston, and the first sleeve and the first spacer vessel defines a first atmospheric chamber, and wherein the volume arranged between a rear face of the second piston, and the second sleeve and the second spacer vessel defines a second atmospheric chamber,
[0028] - at least a first sealing system arranged on the first piston,
[0029] - at least a second sealing system arranged on the second piston, and - a hydrogen leak detection system as described above.
[0030] The invention also relates to a method for detecting hydrogen leaks in a hydrogen compression machine, where the hydrogen compression machine comprises:
[0031] - at least one pressure multiplier, which in turn comprises: - at least one stem connectable at a first end to a first piston movable inside a first sleeve arranged adjacent to a first spacer vessel and connectable at a second end to a second piston movable inside a second sleeve arranged adjacent to a second spacer vessel, wherein the volume arranged between a rear face of the first piston, and the first sleeve and the first spacer vessel defines a first atmospheric chamber, and wherein the volume arranged between a rear face of the second piston, and the second sleeve and the second spacer vessel defines a second atmospheric chamber, and
[0032] - at least a first sealing system arranged on the first piston; and - at least a second sealing system arranged on the second piston; wherein the hydrogen leak detection method comprises:
[0033] - a stage for detecting the concentration of hydrogen in air, inert gas or a mixture of both coming from the first atmospheric chamber;
[0034] - a stage for detecting the concentration of hydrogen in air, inert gas or a mixture of both coming from the second atmospheric chamber;
[0035] - a stage where it is determined whether the concentration of hydrogen in air, inert gas or mixture of both from the first atmospheric chamber detected in the corresponding detection stage and / or whether the concentration of hydrogen in air, inert gas or mixture of both from the second atmospheric chamber detected in the corresponding detection stage is above a first threshold value, and consequently, it is determined whether the at least one first sealing system arranged in the first piston and / or the at least one second sealing system arranged in the second piston must be replaced.
[0036] Optionally, the method comprises an air, inert gas, or mixture of both inlet stage to the first atmospheric chamber and an air, inert gas, or mixture of both outlet stage from the second atmospheric chamber, or vice versa, wherein the air, inert gas, or mixture of both entering through the at least one air, inert gas, or mixture of both inlet is ambient air, inert gas, or mixture of both which mixes in the first atmospheric chamber or the second atmospheric chamber with hydrogen escaping through the at least one first sealing system or the at least one second sealing system, respectively, and wherein the air, inert gas, or mixture of both exiting through the at least one air, inert gas, or mixture outlet has a hydrogen concentration that is evaluated by the at least one hydrogen sensor. DESCRIPTION OF THE DRAWINGS
[0037] To complement the description being made and in order to help a better understanding of the characteristics of the invention, according to a preferred embodiment thereof, a set of drawings is included as an integral part of said description, in which, for illustrative and non-limiting purposes, the following has been represented:
[0038] Figure 1 shows a cross-sectional view of the hydrogen leak detection system in a hydrogen compression machine of the present invention. A pressure multiplier with a stem attached to a piston movable from left to right is depicted. On the left is the point of expulsion of air, inert gas, or a mixture of both, through which the detection system can determine whether or not there is a leak in the hydrogen chamber, represented during the filling phase of the hydrogen chamber in the first stage of the pressure multiplier. On the right is the point of injection of air, inert gas, or a mixture of both, carried out through the detection system to determine whether or not there is a leak in the atmospheric chamber, represented during the hydrogen compression phase of the second stage of the pressure multiplier.
[0039] Figure 2 shows a cross-sectional view of the hydrogen leak detection system in a hydrogen compression machine of the present invention, where the same pressure multiplier as in Figure 1 is shown, but where the rod attached to the piston is now displaced from right to left. The point of expulsion of air, inert gas, or a mixture of both in Figure 1 becomes the point of injection of air, inert gas, or a mixture of both, and vice versa.
[0040] Figure 3.- Shows a detailed view of the hydrogen leak detection system of the present invention comprising four hydrogen sensors.
[0041] PREFERRED EMBODIMENT OF THE INVENTION
[0042] The following describes, with the aid of figures, a preferred embodiment of the hydrogen leak detection system in a hydrogen compression machine according to the present invention, wherein the hydrogen compression machine comprises:
[0043] - at least one pressure multiplier, which in turn comprises:
[0044] - at least one rod (1) connectable at a first end (2) to a first piston (3) displaceable inside a first sleeve (4) arranged adjacent to a first spacer vessel (5), wherein the at least one rod (1) is connectable at a second end (6) to a second piston (7) displaceable inside a second sleeve (8) arranged adjacent to a second spacer vessel (9), wherein the volume disposed between a rear face (10) of the first piston (3), and the first sleeve (4) and the first spacer vessel (5) defines a first atmospheric chamber (11), and wherein the volume disposed between a rear face (12) of the second piston (7), and the second sleeve (8) and the second spacer vessel (9) defines a second atmospheric chamber (13), and
[0045] - at least one first sealing gasket (14) arranged on the first piston (3); and - at least one second sealing gasket (15) arranged on the second piston (7);
[0046] where the hydrogen leak detection system comprises:
[0047] - a first vent duct (16) connecting the first atmospheric chamber (11) with at least one hydrogen sensor (17, 18) configured to detect the concentration of hydrogen in the air in the first atmospheric chamber (11);
[0048] - a second vent duct (19) connecting the second atmospheric chamber (13) with at least one hydrogen sensor (17, 18) configured to detect the concentration of hydrogen in the air in the second atmospheric chamber (13);
[0049] - a control unit (20) configured to determine if the hydrogen concentration in air from the first atmospheric chamber (11) and / or the second atmospheric chamber (13) is above a first threshold value (U1), and consequently, to determine if at least one first sealing gasket (14) disposed on the first piston (3) and / or at least one second sealing gasket (15) disposed on the second piston (7) should be replaced.
[0050] In the embodiment shown in Figures 1 and 2, the at least one stem (1) attachable at a first end (2) to a first piston (3) movable inside a first sleeve (4) arranged adjacent to a first spacer cup (5) and attachable at a second end (6) to a second piston (7) movable inside a second sleeve (8) arranged adjacent to a second spacer cup (9), is, in use, in contact with the first movable piston (3).
[0051] In the embodiment shown in Figures 1 and 2, the at least one stem (1) comprises a first section (31) connectable at the first end (2) to the first piston (3) displaced inside the first sleeve (4) arranged adjacent to the first spacer cup (5), wherein the first section (31) is connectable at a third end (32) to a third piston (33) displaced inside a chamber (34) of a drive system, wherein the at least one stem (1) comprises a second section (35) connectable at the second end (6) to the second piston (7) displaced inside the second sleeve (8) arranged adjacent to the second spacer cup (9), wherein the second section (35) is connectable at a fourth end (36) to the third piston (33) displaced inside the chamber (34) of the drive system.
[0052] As can be seen in Figures 1 and 2, the hydrogen leak detection system comprises a first hydrogen sensor (17) communicated with the first atmospheric chamber (11) through the first vent duct (16) and configured to detect the concentration of hydrogen in the air in said first atmospheric chamber (11) and a second hydrogen sensor (18) communicated with the second atmospheric chamber (13) through the second vent duct (19) and configured to detect the concentration of hydrogen in the air in said second atmospheric chamber (13).
[0053] The distance between at least one hydrogen sensor (17, 18) and the first vent duct (16) and / or the second vent duct (19) is in the range between 0 and 500mm, preferably between 0 and 300mm, more preferably between 0 and 150mm
[0054] For this embodiment example, the diameter of the first vent pipe (16) and / or the second vent pipe (19) is between 3mm and 80mm, preferably being 10mm.
[0055] In this embodiment, the first vent pipe (16) and / or the second vent pipe (19) comprise at least a first vertical section and at least one horizontal section.
[0056] As shown in Figure 3, the hydrogen leak detection system comprises a labyrinth-shaped set of baffles (21) arranged between the first vent duct (16) and / or the second vent duct (19) and the hydrogen sensor (17, 18). This set of baffles (21) is configured to guide the hydrogen-laden air and protect the sensor (17, 18) from the ingress of dirt and / or particles. Preferably, the set of baffles (21) is mounted on a tube-shaped support (22), preferably with a square cross-section.
[0057] Optionally, at least one hydrogen sensor (17, 18) is arranged above at least one pressure multiplier (100), since the density of hydrogen is less than that of air, and hydrogen will always flow upwards.
Claims
CLAIMS 1. Hydrogen leak detection system in a hydrogen compression machine, where the hydrogen compression machine comprises: - at least one pressure multiplier, which in turn comprises: - at least one rod (1) coupled at a first end (2) to a first piston (3) displaced inside a first sleeve (4) arranged adjacent to a first spacer vessel (5), wherein the at least one rod (1) is coupled at a second end (6) to a second piston (7) displaced inside a second sleeve (8) arranged adjacent to a second spacer vessel (9), wherein the volume disposed between a rear face (10) of the first piston (3), and the first sleeve (4) and the first spacer vessel (5) defines a first atmospheric chamber (11), and wherein the volume disposed between a rear face (12) of the second piston (7), and the second sleeve (8) and the second spacer vessel (9) defines a second atmospheric chamber (13), and - at least a first sealing system (14) arranged on the first piston (3); and - at least a second sealing system (15) arranged on the second piston (7); characterized in that the hydrogen leak detection system comprises: - a first vent duct (16) connecting the first atmospheric chamber (11) with at least one hydrogen sensor (17, 18) configured to detect the concentration of hydrogen in air, inert gas or a mixture of both in the first atmospheric chamber (11); - a second vent duct (19) connecting the second atmospheric chamber (13) with at least one hydrogen sensor (17, 18) configured to detect the concentration of hydrogen in air, inert gas or a mixture of both in the second atmospheric chamber (13); - a control unit (20) configured to determine if the concentration of hydrogen in air, inert gas or mixture of both coming from the first atmospheric chamber (11) and / or the second atmospheric chamber (13) is above a first threshold value (U1), and consequently, to determine if the at least one first sealing system (14) disposed in the first piston (3) and / or the at least one second sealing system (15) disposed in the second piston (7) must be replaced.2.Hydrogen leak detection system in a hydrogen compression machine according to claim 1 characterized in that at least one rod (1) coupled at a first end (2) to a first piston (3) displaced inside a first sleeve (4) arranged adjacent to a first spacer cup (5) and coupled at a second end (6) to a second piston (7) displaced inside a second sleeve (8) arranged adjacent to a second spacer cup (9), is fixed to the first movable piston (3) and to the second movable piston (7).
3. Hydrogen leak detection system in a hydrogen compression machine according to claim 1 characterized in that the at least one rod (1) coupled at a first end (2) to a first piston (3) displaced inside a first sleeve (4) arranged adjacent to a first spacer cup (5) and coupled at a second end (6) to a second piston (7) displaced inside a second sleeve (8) arranged adjacent to a second spacer cup (9), is, in use, in contact with the first movable piston and the second movable piston.
4. Hydrogen leak detection system in a hydrogen compression machine according to any of the preceding claims, characterized in that it comprises a first hydrogen sensor (17) communicated with the first atmospheric chamber (11) through the first vent duct (16) and configured to detect the hydrogen concentration in air, inert gas or mixture of both in said first atmospheric chamber (11) and a second hydrogen sensor (18) communicated with the second atmospheric chamber (13) through the second vent duct (19) and configured to detect the hydrogen concentration in air, inert gas or mixture of both in said second atmospheric chamber (13).
5. Hydrogen leak detection system in a hydrogen compression machine according to any of the preceding claims, characterized in that the distance between the at least one hydrogen sensor (17, 18) and the first vent duct (16) and / or the second vent duct (19) is in the range between 0 and 500mm.
6. Hydrogen leak detection system in a hydrogen compression machine according to any of the preceding claims, characterized in that the diameter of the first vent pipe (16) and / or the second vent pipe (19) is between 3 mm and 80 mm.
7. Hydrogen leak detection system in a hydrogen compression machine according to any of the preceding claims, characterized in that the first vent pipe (16) and / or the second vent pipe (19) comprise at least a first vertical section and at least one horizontal section.
8. Hydrogen leak detection system in a hydrogen compression machine according to any of the preceding claims, characterized in that the internal volume of the first vent duct (16) and / or the second vent duct (19) is at least 50% less than the internal volume of the first atmospheric chamber (11) and / or the second atmospheric chamber (13), respectively.
9. Hydrogen leak detection system in a hydrogen compression machine according to any of the preceding claims, characterized in that it comprises a set of deflectors (21) arranged between the first vent duct (16) and / or the second vent duct (19), and the at least one hydrogen sensor (17, 18), the set of deflectors (21) being configured to guide air, inert gas or a mixture of both with hydrogen and to protect the sensor (17, 18) from the entry of dirt and / or particles.
10. Hydrogen leak detection system in a hydrogen compression machine according to claim 9 characterized in that the deflector assembly (21) is arranged in a tube-shaped support (22).
11. Hydrogen leak detection system in a hydrogen compression machine according to claim 10 characterized in that the tube-shaped support (22) has a square cross-section.
12. Hydrogen leak detection system in a hydrogen compression machine according to any of claims 9 to 11, characterized in that the deflector assembly (21) has a labyrinth shape.
13. Hydrogen leak detection system in a hydrogen compression machine according to any of claims 9 to 11, characterized in that the deflector assembly (21) has a grid shape.
14. Hydrogen leak detection system in a hydrogen compression machine according to any of the preceding claims, characterized in that the at least one hydrogen sensor (17, 18) is arranged above the at least one pressure multiplier (100).
15. A hydrogen leak detection system in a hydrogen compression machine according to any of the preceding claims, characterized in that the pressure multiplier (100) comprises at least one air, inert gas, or mixture inlet disposed in the first atmospheric chamber (11) and at least one air, inert gas, or mixture outlet disposed in the second atmospheric chamber (13), or vice versa, wherein the air, inert gas, or mixture entering through the at least one air, inert gas, or mixture inlet is ambient air, inert gas, or mixture which mixes in the first atmospheric chamber (11) or in the second atmospheric chamber (13) with the hydrogen escaping through the at least one first sealing system (14) or the at least one second sealing system (15), respectively, and wherein the air, inert gas, or mixture exiting through the at least one air outlet,inert gas or mixture of both presents a hydrogen concentration that is evaluated in at least one hydrogen sensor (17, 18).
16. Hydrogen compression machine comprising: - at least one pressure multiplier, which in turn comprises: - at least one rod connectable at a first end to a first piston movable inside a first sleeve arranged adjacent to a first spacer vessel, wherein the at least one rod is connectable at a second end to a second piston movable inside a second sleeve arranged adjacent to a second spacer vessel, wherein the volume arranged between a rear face of the first piston, and the first sleeve and the first spacer vessel defines a first atmospheric chamber, and wherein the volume arranged between a rear face of the second piston, and the second sleeve and the second spacer vessel defines a second atmospheric chamber, - at least a first sealing system arranged on the first piston; - at least a second sealing system arranged on the second piston; and - a hydrogen leak detection system according to any of the preceding claims.
17. Method for detecting hydrogen leaks in a hydrogen compression machine, where the hydrogen compression machine comprises: - at least one pressure multiplier, which in turn comprises: - at least one rod connectable at a first end to a first piston movable inside a first sleeve arranged adjacent to a first spacer vessel, wherein the at least one rod is connectable at a second end to a second piston movable inside a second sleeve arranged adjacent to a second spacer vessel, wherein the volume disposed between a rear face of the first piston, and the first sleeve and the first spacer vessel defines a first atmospheric chamber, and wherein the volume disposed between a rear face of the second piston, and the second sleeve and the second spacer vessel defines a second atmospheric chamber, and - at least a first sealing system arranged on the first piston; and - at least a second sealing system arranged on the second piston; wherein the hydrogen leak detection method comprises: - a stage for detecting the concentration of hydrogen in air, inert gas or a mixture of both coming from the first atmospheric chamber; - a stage for detecting the concentration of hydrogen in air, inert gas or a mixture of both coming from the second atmospheric chamber; - a stage where it is determined whether the concentration of hydrogen in air, inert gas or mixture of both from the first atmospheric chamber detected in the corresponding detection stage and / or whether the concentration of hydrogen in air, inert gas or mixture of both from the second atmospheric chamber detected in the corresponding detection stage is above a first threshold value, and consequently, it is determined whether the at least one first sealing system arranged in the first piston and / or the at least one second sealing system arranged in the second piston must be replaced.
18. Method for detecting hydrogen leaks in a hydrogen compression machine according to claim 17, characterized in that it comprises an air, inert gas or mixture of both inlet stage to the first atmospheric chamber (11) and an air, inert gas or mixture of both outlet stage from the second atmospheric chamber (13), or vice versa, wherein the inlet air, inert gas or mixture of both is ambient air, inert gas or mixture of both which is mixed in the first atmospheric chamber (11) or in the second atmospheric chamber (13) with the hydrogen escaping through at least one first sealing system (14) or at least one second sealing system (15), respectively, and wherein the outlet air, inert gas or mixture of both has a hydrogen concentration which is evaluated in at least one hydrogen sensor (17, 18).