EP2173440B1 - Device and method for fire-prevention and for extinguishing a fire that has broken out in an enclosed area - Google Patents

Description

The present invention relates to an inerting process for fire prevention and fire extinguishing in an enclosed space, in particular laboratory space, the room atmosphere supplied in a regulated manner fresh air as supply air and discharged from the room atmosphere in a controlled manner exhaust air, and wherein in case of fire or to avoid fire the room atmosphere under normal conditions gaseous extinguishing agent is supplied as supply air. The invention further relates to a device for extinguishing a fire that has broken out in an enclosed space, the device having at least one device for providing a gaseous extinguishing agent under normal conditions and for suddenly introducing the gaseous extinguishing agent into the room atmosphere of the enclosed space when in the enclosed space Fire broke out.

The publication DE 10 2005 023 101 A1 relates to a method for introducing an inert gas into an enclosed space, wherein the compressed inert gas is passed into the extinguishing or protective area at approximately constant throughput.

The publication DE 102 49 126 A1 relates to a method for generating an oxygen-free atmosphere in a room from which the oxygen-containing air is pumped out and replaced by an oxygen-poor gas, wherein in the evacuated from the room or the ambient air, the oxygen content is filtered out and released into the atmosphere and the filtered, largely oxygen-free air is pumped into the room to be intertisierten.

The publication DE 44 13 074 A1 relates to a method for inerting reactors.

The publication US 2001/0029750 A1 relates to a particular breathable inert gas composition as well as a system for fire prevention and fire extinguishment with such an extinguishing composition.

The publication EP 1 683 548 A1 relates to an inerting method for preventing a fire or an explosion in a first enclosed protection area, in which the oxygen content in the protected area is lowered relative to the ambient air to a basic inerting level.

The publication US 2003/0226669 A1 relates to a similar inertization process.

From the fire-extinguishing technique, it is known to supply in the event of a fire or to avoid a fire in an enclosed space of the room atmosphere under normal conditions gaseous extinguishing agent. For example, in the document DE 198 11 851 A1 a system (method and apparatus) for fire extinguishing in confined spaces described. In this conventional system, depending on a fire detection signal in the room atmosphere of the enclosed space under normal condition gaseous, oxygen-displacing extinguishing agent (hereinafter also simply called "inert gas") suddenly, ie within the shortest possible time initiated. By introducing the inert gas, the oxygen content in the indoor air atmosphere lowered to a certain pre-definable "inerting level". This level of inertization corresponds to a reduced oxygen content at which the flammability of the goods or materials stored in the room has already been reduced to such an extent that they can no longer ignite or an already broken-out fire is stifled.

The extinguishing effect resulting from the flooding of an enclosed space with inert gas is based on the principle of oxygen displacement. "Normal" ambient air is known to be 21% by volume of oxygen, 78% by volume of nitrogen and 1% by volume of other gases. To extinguish or as a preventive fire protection measure by introducing inert gas, the oxygen content in the room atmosphere of the room in question is reduced. It is known that a extinguishing effect or a preventive fire protection begins when the oxygen content of the room atmosphere drops below a so-called "re-ignition prevention level". The re-ignition prevention level is an inerting level which corresponds to a reduced oxygen concentration at which the goods or materials stored in the respective room can no longer ignite or burn. Thus, the level of backfire prevention, which is usually determined by experiment, depends on the fire load of the protected area. In general, the oxygen content corresponding to the backfire prevention level is in a range between 12% by volume to 15% by volume. However, for highly flammable substances, such as volatile solvents, the oxygen content corresponding to the rate of re-ignition prevention may be less than 12% by volume.

According to a recent guideline issued by the Association of Property Insurers (VdS), when flooding an enclosed space ("protection area"), the oxygen concentration in the protection area should reach the reburn prevention level within the first 60 seconds from the start of flooding. In this way, an effective fire fighting is possible with the inert gas extinguishing, so that within the fire-fighting phase, a fire in the protection area can be completely extinguished.

In order to meet these requirements, it is necessary, especially in large-volume rooms, such as laboratories, production rooms or warehouses, that if necessary as quickly as possible, ie within the required 60 seconds in the VdS directive, a sufficient amount of inert gas in the room atmosphere the enclosed space can be introduced.

For this purpose, it is advisable that the oxygen-displacing gases used in the inert gas extinguishing technology are stored compressed, for example in steel cylinders. Alternatively or additionally, it is conceivable to provide a device for generating an oxygen-displacing gas, such as a so-called "nitrogen generator", although the amount of inert gas which can be supplied by the device per unit of time must be adapted correspondingly to the volume of the protected area. This is especially true if in addition to the nitrogen generator no further inert gas source is provided. If necessary, then the provided amount of inert gas, for example via piping systems and corresponding outlet nozzles, as quickly as possible in the room in question.

Due to the requirement that in the inert gas extinguishing at least at the beginning of flooding an oxygen displacing gas must be introduced as quickly as possible in the enclosed space to allow safe and effective fire fighting, a structural pressure relief is inevitable for the enclosed space to damage at least parts to prevent the envelope surrounding the room. Such pressure relief is usually realized by installing pressure relief valves. The task of pressure relief valves is to protect the shell of the enclosed space from damage, even if in the interior of the room, for example, by the sudden introduction of a gaseous extinguishing agent, a relatively high internal pressure is built up. Often it is intended that the pressure relief valves are designed so that they open independently at a pre-empirically determined pressure. By opening the pressure relief flaps, an opening is provided in the shell of the enclosed space through which the overpressure built up in the interior of the room can escape. It is known that the pressure relief valves close again after the escape of the overpressure, so when a pressure relief has taken place. For the technical realization of the independent opening and closing of the pressure relief flap, it is known to use a mechanism with a spring-loaded bolt.

The disadvantage of such a mechanical pressure relief is the fact that the pressure relief surface to be considered must already be estimated in the planning phase before the structural completion of the enclosed space. Furthermore, the dimensioning of the pressure relief flaps to be installed is also to be defined in the planning phase. In particular, it is to be estimated in advance which effective air or gas passage area to be provided with the pressure relief flap.

In the design and dimensioning of the pressure relief flaps used in the conventional manner often assumed in the enclosed space theoretically occurring overpressure. For reasons of planning security, this theoretical value often has to be provided with a more or less generous safety surcharge in order to allow for even unscheduled pressure loads. However, the installation of oversized pressure relief flaps is disadvantageous in terms of cost.

Furthermore, an enclosed space, which is already equipped with a conventional inert gas fire extinguishing system, is often only conditionally convertible or expandable. For example, if restructuring is required to increase the volume of space by means of structural measures, additional pressure relief dampers may be required to meet the required safety requirements.

Also allows the previously known approach to provide a pressure relief or only with greater structural complexity that in a room that is already equipped with a conventional inert gas fire extinguisher and a conventional pressure relief, in the room atmosphere deliberately set before flooding with inert gas, artificial Maintain pressure ratio during flooding. This requirement must be taken into account, for example, in laboratories whose room pressure is permanently reduced in comparison with the ambient pressure in order to prevent, for example, the escape of harmful particles, substances, viruses, etc., with the aid of the negative pressure set inside the room. This protective mechanism provided by the permanently set negative pressure would fail if conventional mechanical pressure relief valves are used to relieve pressure, providing a pressure relief port to the outside when needed.

Based on this problem, the invention has the object, further develop a based on the principle of inerting fire extinguishing system and a fire extinguishing method of the type mentioned that for an enclosed space, especially laboratory space in which a permanent negative pressure is set, one at a flooding be provided with inert gas to be provided pressure relief over the largest possible range of the size of the room and the volume, it allows the pressure relief at the same time that even with a rapid introduction of inert gas of the set in the room vacuum is maintained, thus effectively during the Flooding of the room with inert gas an escape of possibly in the space atmosphere existing harmful particles, substances, viruses, etc. to prevent. In particular, the problem to be solved by the present invention is to provide a way in which the air can be removed from the enclosed space in order to maintain a negative pressure.

This object is achieved with regard to the method by the subject-matter of the independent claim 1 and with regard to the device by the subject-matter of the independent claim 11, wherein advantageous developments of the method and the device according to the invention are specified in the respective subclaims.

Accordingly, the device according to the invention in particular a pressure relief device with a vacuum generating means and a controller, wherein the controller is designed to control the negative pressure generating device in response to the prevailing in the room atmosphere of the enclosed space pressure (also called "room pressure") such that the in the room atmosphere prevailing pressure does not exceed a predetermined maximum pressure value.

The term "negative pressure generating device" as used herein basically means any device or device which is designed, for example, to be able to lower the pressure prevailing in the interior of the space by active removal of air or gas from the room atmosphere of the enclosed space. It is essential that the solution proposed herein merely requires that air or gas is removed from the (gaseous) room atmosphere. This can be done, for example, by removing or removing the air or the gas from the volume of the enclosed space via an exhaust air line. However, it is also conceivable that the air or gas quantity to be removed from the room atmosphere for the purpose of pressure relief is not removed from the volume of space, but compressed, for example with the aid of a compressor, and remains in compressed form in the interior of the room, for example by the compressed air - or gas is cached in an accumulator tank. The accumulator tank can be located inside the room or outside the room.

In the method according to the invention, it is provided in particular that, in the method of the type mentioned at the beginning, the instantaneous pressure prevailing in the room atmosphere is measured at least in the method step of the sudden introduction of the extinguishing agent into the room atmosphere and the pressure measured value is compared with a predetermined maximum pressure value. Subsequently, depending on the result of the comparison in the enclosed space, a negative pressure is generated such that the instantaneous pressure measured value does not exceed the predetermined maximum pressure value.

The achievable with the inventive solution advantages are obvious. Accordingly, in the actual sense no "pressure relief", but rather an intelligent pressure compensation is proposed, in which the introduction of extinguishing gas in the

Room interior rising pressure is compensated. In particular, the room pressure set before the flooding in the room atmosphere of the enclosed space is maintained. This applies even if, within a very short time and in particular within the first 60 seconds after the start of the flooding in the room atmosphere, the level of backfire prevention must be set.

In particular, the fact that in the device according to the invention a pressure relief device with a controllable via a control negative pressure generating device is used, it is possible in an advantageous manner to continuously compensate in the room atmosphere of the enclosed space at the time of extinguishing agent introduction building up pressure. By providing the vacuum generating device can be achieved in particular that in the enclosed space basically a negative pressure is generated, the size of which is adapted to the momentary overpressure generated by the introduction of the extinguishing agent. Thus, the overpressure generated by the introduction of the extinguishing agent into the enclosed space can be sufficiently compensated at any time.

The negative pressure that can be provided by the negative pressure generating device is preferably selected such that at least partial compensation of the overpressure is possible, which builds up in the protected area as a result of the sudden introduction of the gaseous extinguishing agent.

mit K = Kompressionsmodul der RaumluftFormulation used under the herein "generating a vacuum" or "providing a negative pressure" is basically an active discharging an air or gas volume Δ V of the spatial atmosphere of the enclosed space to be understood, as a result, the air or gas pressure p in the interior of the space according to the equation given below for the description of the isothermal pressure change by the amount Δ p : $$\mathrm{\Delta }p=-K\frac{\mathrm{\Delta }V}{V}.$$

with K = compression modulus of the room air

According to the invention, it is provided that the vacuum generating device can be controlled via the controller. The activation of the vacuum generating device is preferably carried out such that the pressure prevailing in the room atmosphere pressure does not exceed a predetermined maximum pressure value.

Accordingly, it is possible with the solution according to the invention to use a based on the principle of inerting fire extinguishing system in an enclosed space having an atmosphere which compared to the air pressure of the normal outside atmosphere has a reduced pressure (negative pressure), as for example in laboratories the case may be. With the solution according to the invention, this negative pressure, which is deliberately set in the protected area, is maintained even if, for example, a gaseous extinguishing agent is introduced into the room atmosphere for the purpose of extinguishing a fire. Particularly preferably, it is provided that the maximum pressure value, which is used as a threshold value for the pressure to be maintained in the room atmosphere, is freely definable.

It is essential that the achievable with the solution according to the invention pressure compensation or pressure relief is decoupled from the spatial design of the enclosed space, and in particular the size or the volume of the room, as independent of the volume of space with the pressure relief device itself at the initiation of a gaseous Extinguishing adjusting pressure change in the room can be compensated accordingly. In the solution according to the invention is not the normal atmospheric pressure, but set before the flooding with inert gas in the interior of the room (lower) pressure as a reference for the pressure relief to be provided.

In the method according to the invention is a procedural implementation of the achievable with the device described above fire prevention or fire extinguishing. The advantages described in connection with the device according to the invention can be achieved in the same way also in the inventive method.

In particular, the method according to the invention is a particularly easy-to-implement yet effective method for preventive fire protection and / or for the effective and, in particular, reliable extinguishing of a fire which has broken out in an enclosed space, pressure relief being provided in the form of pressure compensation. With the help of this pressure compensation, it is possible to sufficiently compensate for a change in pressure entering the space atmosphere during the discharge of extinguishing agent, so that in this way damage to the space envelope can be effectively prevented.

This is achieved, in particular, by activating the (gaseous) room atmosphere in the protected area at all times, ie even during introduction of the extinguishing agent Exhaust air is discharged. A reduced in the space compared to the normal air pressure of the outside atmosphere space pressure can be maintained in this way at any time, ie also during the extinguishing agent supply, namely by ensuring that in principle the per unit time of the room atmosphere as a total of fresh air and / or Extinguishing agent supplied gas volume less than or equal to the time per unit as exhaust air from the (gaseous) room atmosphere discharged or removed volume.

Advantageous further developments of the method according to the invention are given in claims 2 to 10 and the device according to the invention in claims 11 to 13.

In principle, in the inerting process according to the invention, the exhaust air can be removed or removed in a regulated manner from the room atmosphere. The term "room atmosphere" as used herein means the gaseous volume of the enclosed space. Accordingly, the term "removal of exhaust air from the room atmosphere" to understand the removal of at least a portion of the exhaust air from the gaseous volume of space.

As already indicated, the removal, i. Removing the exhaust air from the gaseous room atmosphere can be realized in different ways. On the one hand, it makes sense that at least part of the exhaust air is actively sucked out of the room volume via an exhaust air system. Here, the exhaust air is discharged not only from the room atmosphere, but also from the volume of space, i. away. If the exhaust air system is used to remove the exhaust air in a controlled manner, in order to compensate in this way, a rise in the room pressure occurring during the supply of inert gas must - as in the case of fire extinguishing within a very short time a relatively large amount of inert gas is supplied to the room volume - The exhaust system be designed according to that they can suck off or dissipate a corresponding amount of exhaust air within a very short time. However, an exhaust air system with such a large intake volume can often not be realized or only with greater financial expense.

For this reason, a vacuum generating device is provided in the solution according to the invention, which may be carried out separately from the exhaust air system and serves to provide the pressure required for the supply of inert gas pressure compensation.

In this realization, there is a deliberate separation of functions: the negative pressure generating device is designed separately from the exhaust air system and serves to ensure that the pressure prevailing in the room atmosphere (also simply called "room pressure") does not exceed a predefinable maximum pressure value, so that in this way an in the reduced pressure set to the enclosed space is effectively maintained even if a relatively large amount of oxygen-displacing gas is supplied to the room atmosphere in a short time at the beginning of inert gas flooding.

In the solution according to the invention, a compressor is used as the vacuum generating device, which is designed to compress the volume of at least part of the exhaust air to be removed from the gaseous room atmosphere, i. to condense. The compressor is disposed inside the room so that the exhaust air, which is compressed by the compressor, can be stored in a high pressure storage tank in the room.

On the contrary, the compressor serves to reduce the volume of the exhaust air to be removed from the gaseous room atmosphere and in this way to compensate for an overpressure which builds up when inert gas is being flooded.

As already indicated, the compressor and the high-pressure storage container are arranged in the interior of the enclosed space. This embodiment has the advantage that a pressure compensation can be provided without the need for major structural measures. An installation of the compressor inside the room is particularly suitable for rooms that can not or only with great effort with an additional Abluftrohrleitungssystem or can be retrofitted.

In principle, the compressor should have a sufficiently high volume flow rate, so that it can be ensured that the intake volume of the compressor is greater than or equal to the volume flow of the room atmosphere as a whole supplied fresh air and / or as extinguishing supply air. It would therefore be conceivable, for example, to use a turbo-compressor as a compressor, the design of which guarantees a continuous mode of operation and which is distinguished by a high volume pressure set.

As an alternative or in addition to a negative-pressure generating device designed as a compressor, it is of course also conceivable that the exhaust air to be discharged from the room atmosphere is removed from the interior of the room via an exhaust-air piping system.

Particularly in the case of a laboratory room whose room atmosphere may contain hazardous substances, particles or substances (such as viruses), it is preferred that the exhaust air compressed with the aid of the compressor and possibly stored in the high-pressure storage tank only after a suitable treatment, especially filtering and / or or sterilization, is discharged to the outside atmosphere, so as to prevent harmful substances, particles, substances, etc. can be released.

Basically, however, that other solutions are conceivable as a vacuum generating device. For example, it would be conceivable to use devices for reducing the amount of gas in the enclosed space, which are operated with a fan. In one possible realization of the vacuum generating device, it can be provided, for example, that it has a suction device and an intake pipe system connected to the suction device. In this case, it is preferred that with the aid of a controller, the amount of gas or air extracted by means of the suction device via the intake pipe system from the enclosed space per unit time is adjustable. Thus, it is particularly conceivable in this context that the suction device is realized as a fan or identifies a fan whose speed and / or the direction of rotation by means of the control of the pressure relief device is adjustable / is. This is an easy-to-implement but nevertheless effective embodiment of the vacuum generating device, in which with the aid of the control, the pressure compensation which can be effected with the vacuum generating device in the protected area can be carried out particularly accurately. However, as already mentioned above, it must be taken into consideration here that the suction device is designed accordingly in order to discharge a sufficient volume of discharge from the room atmosphere per unit of time to be able to compensate as quickly as possible at the start of flooding pressure increase as possible at the same time.

In the latter embodiment, when a fan is provided as the suction means in which not only the rotation speed but also the rotation means can be adjusted by the control, it is possible to use the suction means as the blow-out means. A blow-out device is a device that is designed, for example, to allow active ventilation of the enclosed space. The provision of such a blow-out device can be particularly advantageous if, for example, after a fire extinguishment of the existing smoke in the room must be removed, or if (for whatever reason) fresh air must be introduced into the room.

With regard to the pressure relief or pressure compensation that can be realized with the solution according to the invention, it is preferred if the respective volume flows of the fresh air supplied as supply air, the discharged exhaust air and the extinguishing agent supplied as supply air in case of fire or fire prevention are measured, and then the respective ones Volumetric flows are controlled so that at any time, the difference between the volume flow of the room atmosphere as fresh air and / or as extinguishing agent supplied supply air and the volume flow of exhaust air discharged from the room atmosphere assumes a constant pre-definable value. If the enclosed space has a gas- and aerosol-tight space envelope, this pre-settable value should be zero to ensure that a room pressure set in the enclosed space, in spite of the supply of fresh air and / or inert gas (possibly with a certain amount of air) Control range) is maintained. By being able to set the difference between the volume flow of the supply air and the volume flow of the exhaust air to a pre-definable value, it is also possible to deliberately change (increase or decrease) the room pressure in a controlled manner.

Alternatively or in addition to the aforementioned regulation, it is advantageous if the difference between the pressure prevailing in the room (room pressure) and the air pressure of the outside atmosphere is determined continuously and at predeterminable times and / or events and compared with a predeterminable value, and if the volume flow of the supply air supplied to the room atmosphere as fresh air and / or as extinguishing agent and the volume flow of the exhaust air discharged from the room atmosphere are regulated as a function of the comparison. This is a particularly easy-to-implement, yet effective way to perform effective pressure compensation in the enclosed space, even if within the shortest possible time Time is supplied in particular at the beginning of a fire-fighting phase per unit time a large amount of inert gas of the room atmosphere as supply air.

• dass der Volumenstrom der der Raumatmosphäre insgesamt als Frischluft und/oder als Löschmittel zugeführten Zuluft gleich groß wie der Volumenstrom der aus der Raumatmosphäre abgeführten Abluft ist, wenn die ermittelte Differenz zwischen dem Raumdruck und dem Luftdruck der Umgebungsluft vom vorgegebenen Wert entspricht; und/oder
• dass der Volumenstrom der der Raumatmosphäre insgesamt als Frischluft und/oder als Löschmittel zugeführten Zuluft kleiner als der Volumenstrom der aus dem Raumatmosphäre abgeführten Abluft ist, wenn die ermittelte Differenz zwischen dem Raumdruck und dem Luftdruck der Umgebungsluft kleiner als der vorgegebenen Wert ist.

In the case of the last-mentioned development, the comparison and the control carried out subsequently are preferably carried out with the aid of a controller. In this case, the controller should be designed to control an air supply system associated with the room, an inert gas source connected to the room, and an exhaust air system associated with the room, and optionally a vacuum generating device,

• the volume flow of the supply air supplied to the room atmosphere as fresh air and / or as extinguishing agent is equal to the volume flow of the exhaust air discharged from the room atmosphere, if the determined difference between the room pressure and the air pressure corresponds to the ambient air from the predetermined value; and or
• in that the volume flow of the supply air supplied to the room atmosphere as fresh air and / or as extinguishing agent is smaller than the volume flow of the exhaust air discharged from the room atmosphere, if the determined difference between the room pressure and the air pressure of the ambient air is smaller than the predetermined value.

It should be noted that the difference between the air pressure in the room and the air pressure of the outside atmosphere can be detected by measuring the pressure (room pressure) prevailing in the room and the air pressure of the outside atmosphere.

As a pressure measuring device, for example, manometers come into question, in which the outside air pressure, ie, the air pressure of the outside atmosphere is used as a reference pressure. Of course, it is also conceivable the use of barometers, so pressure measuring devices in which a vacuum is used as a reference. For the realization of the pressure measuring device are basically so-called "direct pressure gauges" conceivable, which use the force of the pressure to be detected, for example by mechanical, capacitive, inductive, piezorezessiv or strain gauges, the force of the pressure passed and converted into corresponding signals. On the other hand, of course, so-called "indirect pressure measuring devices" are conceivable in which on the measurement of particle number density, heat conduction, etc., a conclusion on the pressure prevailing in the room atmosphere of the enclosed space a statement is made.

In addition or as an alternative to a pressure measuring device, it is, of course, also conceivable to calculate the pressure in the atmosphere of the room by calculation. In such a pressure calculation, the volume of the enclosed space on the one hand and the amount of extinguishing agent introduced into the enclosed space on the other hand should preferably be taken into account. Of course, other embodiments are also conceivable here.

As already indicated, the method according to the invention serves to set an inerting level in the room in the event of a fire by supplying an oxygen-displacing gas (inert gas) within the shortest possible time after a fire detection of the room atmosphere. In order to detect a fire as early as possible and initiate the fire-fighting phase, it is advantageous if it is measured continuously or at predeterminable times and / or events in the room atmosphere, if at least one fire characteristic is present, wherein in the case of detection a fire characteristic of the room atmosphere, the extinguishing agent is supplied as supply air. At the same time, the supply of fresh air should be stopped. In this way, it is possible to relatively quickly set the recirculation-preventing level characteristic of the enclosed space. Of course, it is also conceivable that in the case of a fire, the fresh air supply is not completely adjusted but only throttled. Under certain circumstances, this can be useful if, for example, a swelling fire with heavy smoke has broken out and has to be combated.

Accordingly, it is provided in a preferred development of the device according to the invention that it has a device for detecting at least one fire characteristic in the room atmosphere of the enclosed space. In addition, the system according to the invention should have an extinguishant supply device that can be controlled by a controller. This control is preferably designed to control the extinguishing agent supply device in a fire such that the provided extinguishing agent is supplied directly, and thus in the shortest possible time, the room atmosphere of the enclosed space.

The term "fire characteristic" is understood to mean physical quantities which undergo measurable changes in the environment of a fire of origin, for example the ambient temperature, the solid or liquid or gas component in the room atmosphere (formation of smoke in the form of particles or aerosols or steam) or the ambient radiation.

The device for detecting at least one fire parameter can be designed, for example, as an aspiratively operating system in which a representative subset of the room atmosphere is actively taken in via a pipeline or channel system, preferably at a plurality of locations. This subset can then be forwarded to a measuring chamber with the detector for detecting a fire parameter. Of course, however, fire characteristic sensors are conceivable, which are installed, for example, inside the enclosed space.

In a preferred embodiment, the extinguishant supply device that can be controlled by the controller has a supply line system that is connected on the one hand to an inert gas source, i. a device which provides the gaseous extinguishing agent. On the other hand, the supply line system should be connected to the interior of the enclosed space via gas outlet nozzles. The gas outlet nozzles are preferably distributed inside the enclosed space. The control of the extinguishing agent supply device can be done by a suitable control of control valves or the like devices.

Of course, it is not absolutely necessary in this case for the extinguishing agent supply device to have a supply piping system which connects the inner region of the enclosed space to an inert gas source arranged outside the enclosed space. Rather, it is also conceivable that the inert gas source, for example, has at least one arranged within the enclosed space high-pressure tube. In this at least one arranged within the enclosed space high-pressure tube, at least a portion of the provided extinguishing agent can be stored under high pressure. In this case, it is preferred that the at least one high-pressure pipe has an outlet valve that can be controlled by the control and that is assigned to the extinguishing-agent supply device.

Such a high-pressure pipe may for example also be arranged in a false ceiling of the enclosed space or under the ceiling of the room in order to store the extinguishing agent therein. In a preferred manner, the high-pressure tube should be designed for a pressure range between 20 and 30 bar. Of course, other pressures are conceivable here as well.

In particular, it is advantageous for a plurality of controllable outlet valves to be arranged on the at least one high-pressure pipe, in order, if necessary, to allow the gaseous extinguishing agent to flood as rapidly as possible in the enclosed space.

Alternatively or in addition to the last-mentioned embodiment, in which at least part of the extinguishing agent provided is stored under high pressure in at least one high-pressure pipe, it is also conceivable that the inert gas source has at least one high-pressure bottle, and preferably a battery of high-pressure bottles. These high-pressure bottles can be arranged outside the enclosed space. In this case, a feed pipe system belonging to the extinguishing agent supply device is to be provided, which connects the at least one high-pressure bottle or the battery of high-pressure bottles to the interior of the enclosed space.

Such high-pressure bottles can be, for example, commercial high-pressure bottles, which are designed for a pressure range between 200 to 300 bar. Of course, other means for providing the extinguishing agent or for storage of the extinguishing agent come into question. It is essential that the extinguishing agent provided in the event of a fire quickly, so in the shortest possible time, can be introduced into the enclosed space to effectively prevent a fire or fire in the room can spread. In particular, the fastest possible fire extinguishing is thus effected.

Suitable gaseous extinguishing agents are on the one hand inert gases, such as argon, nitrogen, carbon dioxide or mixtures thereof, i. so-called inerge or argonite. On the other hand, the solution according to the invention can also be carried out with chemical extinguishing agents.

The extinguishing effect of inert gases is achieved by a displacement of atmospheric oxygen. One speaks here of a so-called "Stickeffekt", which occurs when falling below a required for combustion specific limit value. In most cases, the fire is extinguished even at a re-ignition prevention level, which corresponds to a reduction of the oxygen content to 13.8 vol .-%. For this purpose, the existing air volume must only be displaced by about one third, which corresponds to a quenching gas concentration of 34 vol .-%. For fires that require considerably less oxygen for combustion, a correspondingly higher extinguishing gas concentration is required. This would be the case for example with acetylene, carbon monoxide and hydrogen.

As already indicated, and chemical extinguishing agents can be used, however, as a gaseous extinguishing agents, such as HFC-227ea or PRINOVEC ^® 1230. In the known under the ISO designation HFC-227ea extinguishing agent is (the fire or fire by physically for the most part the action Cooling) and a low chemisehen Intervention in the combustion process, the heat extracted, whereby a fire extinction is achieved. With this extinguishing agent a fast extinguishing effect is achieved. Also, there are few restrictions of use as long as the extinguishing area is relatively dense to achieve and maintain the necessary extinguishing agent concentration. At high temperatures, however, unwanted decomposition products can arise during the extinguishing process, which are critical to health.

The chemical extinguishing agent NOVEC ^® 1230 is a particularly environmentally friendly chemical extinguishing agent and is degraded in the atmosphere within approx. 5 days. Furthermore, this chemical extinguishing agent has no negative impact on the ozone layer and on the greenhouse effect.

However, the solution according to the invention is not only suitable for cases in which a fire has already broken out in the enclosed space, whereby firefighting takes place by sudden introduction of the gaseous extinguishing agent. On the contrary, the solution according to the invention is also suitable for effective pressure relief or pressure compensation if no fire has broken out in the enclosed space, whereby only the risk of the occurrence of a fire in the enclosed space should be effectively prevented. For such an inertization-based preventive measure, it is necessary to provide an inert gas or an inert gas mixture as the gaseous "extinguishing agent". In this case, this inert gas or inert gas mixture is supplied in such an amount to the room atmosphere of the enclosed space that the oxygen content in the room atmosphere is lowered to a value at which the flammability of the goods stored in the enclosed space is already reduced to such an extent that they cease to exist can ignite. For materials that show a normal fire behavior, this is the case at about 12 vol.% Oxygen concentration. The supply of the inert gas or inert gas mixture via the already mentioned with the control controllable extinguishing agent supply means.

In order that the solution according to the invention can be used particularly effectively for such a preventive measure, it is preferred that the device further comprises an oxygen measuring device for detecting the oxygen content in the room atmosphere of the enclosed space. Depending on the oxygen content of the room air of the enclosed space, the controller outputs a corresponding control signal to the extinguishing agent supply device. The control signal indicates whether inert gas has to be supplied to the room atmosphere of the enclosed space or whether the supply of the inert gas can be stopped because the critical value of the oxygen content in the room atmosphere has already been reached.

The term "critical value of the oxygen content" is understood here to be the value of the oxygen content at which the flammability of the goods stored in the enclosed space is reduced to such an extent that they can no longer or only with difficulty ignite.

If the solution according to the invention is used as a preventive fire protection measure, it is preferred if the volume flow of inert gas or inert gas mixture supplied to the room atmosphere for preventive fire protection is regulated such that a basic inerting level is initially set and maintained in the room atmosphere, wherein in the event of a fire the volume flow the inert gas or inert gas mixture supplied to the room air atmosphere is controlled such that a Vollinertisierungsniveau is set and maintained.

The term "base inertization level" as used herein means a reduced level of oxygen compared to the oxygen level of normal ambient air, although this reduced level of oxygen does not present any danger to persons or animals, so that they can easily enter the shelter. The basic inerting level corresponds, for example, to an oxygen content in the shelter of 15 vol.%, 16 vol.% Or 17 vol.%.

By contrast, the term "full inertization level" is to be understood as meaning a further reduced oxygen content in comparison to the oxygen content of the basic inertization level at which the flammability of most materials has already been reduced to such an extent that they can no longer be ignited. Depending on the fire load present in the affected shelter, the full inertization level is typically 11% vol or 12% vol oxygen concentration. The Vollinertisierungsniveau should thereby correspond to the re-ignition prevention level. Of course, however, the full inertization level may also correspond to an oxygen concentration which is lower than the oxygen concentration characteristic of the re-ignition prevention level.

Finally, it is still preferred if the quality of the room air is determined continuously or at predeterminable times and / or events in the method according to the invention, wherein the volume flow of the fresh air supplied to the room atmosphere as supply air is regulated as a function of the determined quality of the room air. It is conceivable, for example, to determine the quality of the room air indirectly by measuring the CO ₂ content in the ambient air atmosphere.

In particular, when the solution according to the invention is used in a room, for example a laboratory room whose room atmosphere may contain harmful substances, particles, etc., the exhaust air discharged from the room atmosphere should first be treated, in particular filtered or, if necessary, sterilized before it starts the outside atmosphere is released. Preferably, however, at least some of the exhaust air discharged from the room atmosphere can also be returned to the room atmosphere as fresh air after air treatment.

Fig. 1

eine erste Ausführungsform der erfindungsgemäßen Vorrichtung in einer schematischen Darstellung;

Fig. 2

eine zweite Ausführungsform der erfindungsgemäßen Vorrichtung in einer schematischen Darstellung;

Fig. 3

ein Flussdiagramm zum Erläutern der mit der erfindungsgemäßen Lösung realisierbaren Druckkompensation bzw. Druckentlastung in einem umschlossenen Raum.

Hereinafter, preferred embodiments of the device according to the invention will be described in detail with reference to the accompanying figures. Show it:

Fig. 1

a first embodiment of the device according to the invention in a schematic representation;

Fig. 2

a second embodiment of the device according to the invention in a schematic representation;

Fig. 3

a flowchart for explaining the feasible with the inventive solution pressure compensation or pressure relief in an enclosed space.

Fig. 1 shows a first embodiment of the device according to the invention for extinguishing a fire in an enclosed space 10 broken fire. The device has an inert gas source 11 for providing a gaseous extinguishing agent under normal conditions. In the illustrated embodiment, the inert gas source 11 comprises a gas cylinder battery 11a disposed outside the space 10, in which the extinguishing agent to be provided, such as nitrogen, is stored under high pressure.

The high-pressure bottles 11a are connected to the space 10 via an extinguishing agent supply device 17. In detail, the extinguishing agent supply device 17 comprises on the one hand a supply pipe system 17a and on the other hand a gas outlet nozzle system 17b arranged in the interior of the space 10. The extinguishing agent supply device 17 is designed such that in case of fire (or if necessary) the extinguishing agent stored in the high-pressure bottles 11a can be supplied to the enclosed space 10 as quickly as possible. In particular, the extinguishing gas can thus escape into the room atmosphere of the room 10 via the extinguishing nozzles 17b in a very short time, so that, for example, a full inertisation required for extinguishing the fire can be achieved in the room 10.

In order to ensure that the extinguishing agent stored in the high-pressure bottles 11a can be supplied to the room atmosphere in a controlled manner, the extinguishing agent supply device 17 is further assigned a controllable valve V1, which is completely or only partially opened in case of fire (or if necessary) to connect the high-pressure bottles 11a with the space 10 and to allow the flooding of the space 10 with the gaseous extinguishing agent.

In the Fig. 1 illustrated embodiment of the device according to the invention further comprises a pressure relief device 12. The pressure relief device 12 consists of a vacuum generating device 13 and a controller 14.

The negative pressure generating device 13 is used in the in Fig. 1 schematically illustrated system on the one hand by a suction device 13a and on the other hand by a connected to the suction device 13a intake manifold 13b justified. The intake pipe system 13b is connected to the inside of the enclosed space 10 via intake ports 13c. It can thus be achieved that with the aid of the suction device 13a air or gas can be sucked or removed from the interior of the room and discharged as exhaust air, for example to the outside.

The controller 14 of the vacuum generating device 13 is connected on the one hand to the suction device 13a and on the other hand to a controllable control valve V2 belonging to the vacuum generating device 13. In the illustrated embodiment, the controller 14 accordingly assumes not only the task of controlling the extinguishing agent supply device 17, but also the function of controlling the suction device 13a.

Specifically, the controller 14 is configured to control a function of the pressure prevailing in the spatial atmosphere of enclosed space 10 pressure p _x, the suction means 13a of the vacuum generating means 13 such that the pressure prevailing in the spatial atmosphere of pressure P _x does not exceed a predetermined maximum pressure value p _max. For this purpose, the in Fig. 1 illustrated embodiment, a pressure measuring device 15 for detecting the physical pressure of the present in the room atmosphere of the enclosed space 10 gas. The pressure measuring device 15 is designed to continuously or at predetermined times or events to measure the instantaneous pressure p _x in the room atmosphere and to supply the measured values to the controller 14. The controller 14 controls based on the current pressure value p _x, the negative pressure generating device 13 accordingly, ie at the in Fig. 1 shown Embodiment, the suction device 13a and / or belonging to the vacuum generating device 13 control valve V2. In the controller 14, the pressure p _x currently prevailing in the room atmosphere of the enclosed space 10 is compared with a predefinable maximum pressure value p _max . When the predetermined maximum pressure value p _max is exceeded, the controller 14 outputs a corresponding drive signal, for example, to the suction device 13 a of the vacuum generating device 13.

At the in Fig. 1 illustrated embodiment, the suction device 13a is designed as a fan. With the control signal output when the predetermined maximum pressure value p _max from the controller 14 to the suction device 13a is exceeded, preferably both the rotational speed and the direction of rotation of the fan 13a are set. It can thus be achieved that, in principle, a sufficient amount of gas or air is removed from the atmosphere of the enclosed space 10 per unit time via the intake pipe system 13b connected to the suction device 13a. This ensures that even with a sudden introduction of gaseous extinguishing agent, the instantaneous pressure p _x prevailing in the room atmosphere of the room 10 does not exceed the maximum pressure value p _max .

Of course, it is also conceivable that the instantaneous pressure value p _{x is} not measured, but is calculated or estimated on the basis of the amount of extinguishing agent introduced. In this case, the controller 14 should be designed to control the extinguishing agent supply means 17 accordingly, so that the provided quenching gas is supplied in a regulated manner to the room atmosphere. The regulation of the introduced into the space 10 quenching gas can be done by a corresponding, initiated by the controller control of the already mentioned control valve VI.

In a further development of the solution according to the invention, which also in the in Fig. 1 has received the exemplary embodiment shown, the fire extinguishing system is additionally equipped with a fire detection system 16 for detecting at least one fire characteristic in the room atmosphere of the enclosed space 10. The fire detection system 16 is preferably designed as an aspirative working system, which takes the room atmosphere representative air or gas samples and a (in Fig. 1 not explicitly shown) for at least one fire characteristic feeds.

The signals, preferably continuously or at predetermined times or events, from the fire detection device 16 to the control 14 are transmitted by the controller 14, if appropriate after further processing or evaluation of these signals. used to control the extinguishing agent supply means 17 and / or the control valve V1 accordingly. In detail, it is conceivable that the controller 14 for this purpose emits a corresponding signal to the extinguishing agent supply device 17 when a fire is detected by the fire detection device 16.

As already indicated, is in the in Fig. 1 illustrated embodiment, the controller 14 designed in cooperation with the fan 13 a used as coming to use fan to dissipate in a controlled manner to be discharged from the room atmosphere amount of gas or air through the intake manifold 13 b to the outside. Since with the controller 14 optionally also the direction of rotation of the fan 13a is adjustable, with the vacuum generating means 13, if necessary, a certain amount of air or gas can be introduced into the atmosphere of the enclosed space 10. This can be particularly advantageous if the space 10 is to be moved with respect to the outside atmosphere with a certain overpressure. Accordingly, at the in Fig. 1 In the embodiment shown, the controller 14 is further designed to control the negative pressure generating device 13 as a function of the (instantaneous) pressure p _x prevailing in the room atmosphere of the enclosed space 10 in such a way that the pressure p _x prevailing in the room atmosphere does not fall below a presettable minimum pressure value p _min .

For this purpose, the measured or estimated or calculated, currently present in the enclosed space 10 currently prevailing pressure p _{x should be} compared with the maximum pressure value p _max on the one hand and with the minimum pressure value p _min on the other hand in the controller 14. The negative pressure generating device 13 is to be controlled accordingly if the instantaneous pressure p _{x is} greater than the maximum pressure value p _max or less than the minimum pressure value p _min . The vacuum generating device 13 should be controlled in such a way that the instantaneous pressure p _x prevailing in the room atmosphere of the room 10 does not exceed the maximum pressure value p _max and does not fall below the minimum pressure value p _min .

In principle, in the case of a failure or a malfunction of the vacuum generating device 13, it is generally ensured that the pressure p _x prevailing in the room atmosphere of the enclosed space 10 does not exceed or fall short of the predetermined maximum pressure value p _max and / or the predetermined minimum pressure value p _min , Can be additionally provided as a security measure that the pressure relief device 12 further comprises at least one (mechanical) pressure relief valve 18. The operation of such a pressure relief flap 18 is known in principle from the prior art. The pressure relief flap 18 should be designed that it opens automatically when a predetermined first pressure value p _{1 is} exceeded, to allow a pressure relief in the enclosed space 10.

It is preferred that the optionally provided pressure relief flap 18 is also designed so that it automatically closes again after falling below the predefinable first pressure value p ₁ . The predeterminable first pressure value p ₁ , beyond which the pressure relief flap 18 opens automatically, is preferably greater than or equal to the predefinable maximum pressure value p _max , which is used by the controller 14 as a threshold for controlling the vacuum generating device 13.

In a preferred further development of the last-mentioned embodiment, in which for the purpose of reliability of the pressure relief, the system further comprises at least one preferably mechanically operating pressure relief valve 18, it is provided that the pressure relief valve 18 is further designed so that even when falling below a predetermined second pressure value p ₂ to open automatically and close again after exceeding the predetermined second pressure value p ₂ again. This predefinable second pressure value p ₂ should be less than or equal to the minimum pressure value p _min , which represents the lower threshold value for the activation of the vacuum generating device 13.

In Fig. 2 a further preferred embodiment of the device according to the invention is shown in a schematic representation. In the Fig. 2 illustrated embodiment substantially corresponds to the previously with reference to Fig. 1 described embodiment; However, the system is according to Fig. 2 as negative pressure generating device 13 no suction device is used. Rather, a vacuum 19 provided in the interior of the space 10 is used as negative pressure generating device 13, which serves to compress the volume of at least part of the exhaust air to be discharged from the gaseous room atmosphere, if necessary.

Furthermore, a high-pressure storage tank 20 connected to the compressor 19 is provided, in which the exhaust air compressed by means of the compressor 19 can be temporarily stored. The high-pressure storage tank 20 is connected via a three-way valves V2, V3 with outwardly leading pipe systems 13b, 21, via which, if necessary, compressed with the aid of the compressor 19 exhaust air and / or stored in the high-pressure accumulator tank 20, compressed exhaust air from the interior of the room 10th can be dissipated.

Furthermore, the in Fig. 2 apparatus shown a supply air system consisting of a Zuluftgebläse 22, via which the room atmosphere via the supply pipe system 17a and the outlet nozzle system 17b fresh air can be supplied. In addition, an exhaust air system with an exhaust fan 23 is provided, which is connected via the pipe system 13b and the suction port 13c to the interior of the room 10 and can discharge exhaust air to the outside in a controlled manner. Both the supply air fan 22 and the exhaust fan 23 are controlled accordingly via the controller 14.

In this way, it is possible to provide a deliberate air change in the enclosed space 10 to exchange room air with fresh air or fresh air. For example, in lounges an air exchange is necessary for the supply of oxygen, for the removal of carbon dioxide and for the removal of condensation water. But even in storage rooms that are not or only briefly entered by persons, an air exchange is often essential to remove harmful components that exude, for example, from the housed in the storage room goods. If the building or room envelope is made almost airtight, as it provides the modern design, an unregulated air exchange, which leads to an unwanted and uncontrolled mass transfer between the room atmosphere and the outside atmosphere, no longer take place. In such rooms, the required air exchange can be provided by means of a ventilation system.

A ventilation system is a device which serves to supply fresh air to living or working spaces or to remove "used" or polluted exhaust air. Depending on the application, there are systems with controlled supply air (supply air system), controlled exhaust air (exhaust air system) or combined supply and exhaust air systems.

At the in Fig. 2 In the embodiment shown, a gas cylinder battery 11a, which is connected to the supply pipe system 17a via the three-way valve V1, is used as the inert gas source. Via a branch line 13d and a three-way valve V4, the exhaust pipe system 13b is also connected to the supply pipe system 17a. The valves V2 and V4 can be controlled accordingly by the controller 14, so that the branch line 13d, the valves V2, V4, the exhaust fan 23 and the pipe system 13b establish a recirculation system.

Although in the illustration according to Fig. 2 not explicitly shown, in the supply pipe system 17a, a volumetric flow sensor may be provided to detect the volumetric flow supplied to the room atmosphere in total and the control 14 to detect the detected value to be able to communicate. The total volume flow supplied to the room atmosphere per unit of time is composed of the fresh air volume flow and the inert gas or extinguishing medium volume flow.

Furthermore, although not explicitly stated in Fig. 2 1), a corresponding volume flow sensor may also be provided in the pipe system 13b or 21 in order to detect the exhaust air volume discharged from the interior of the room per unit of time and to communicate the detected value to the control 14. According to the invention, it is provided that the controller 14 compares the detected supply air volume flow with the detected exhaust air volume flow and activates the supply air and / or exhaust air system accordingly so that the supply air volume flow is less than or equal to the exhaust air flow at any time. Volume flow is. In this way, in the space 10 compared to the normal external atmospheric pressure reduced space pressure can be adjusted and / or maintained.

As with the reference to Fig. 1 As described, the controller 14 is designed to control the valve V1 as necessary to form a fluid connection between the inert gas source 11a and the supply pipe system 17a, so that the inert atmosphere (gaseous extinguishing agent) provided by the inert gas source 11a is supplied to the room atmosphere in a controlled manner can. Since it is necessary that in case of fire, the oxygen content in the room atmosphere is lowered to at least the Rückzündungsverhinderungsniveau as soon as possible, in the case of detection of a fire parameter, the supply of fresh air supplied supply air is set, and only extinguishing agent from the inert gas 11a supplied to the room atmosphere. Compared to the normal case, the supply air volume flow increases considerably, which - if no pressure compensation or no pressure compensation would be provided - would lead to an increase in pressure inside the room 10.

To prevent this from happening in the Fig. 2 In the embodiment shown, the negative pressure generating device 13 is used, which compresses the volume of at least part of the exhaust air to be discharged from the room atmosphere and temporarily stores it in the already mentioned high-pressure storage tank 20. The remaining part of the exhaust air to be discharged from the room atmosphere is discharged from the exhaust air system.

By providing the vacuum generating device 13, it is thus possible that the exhaust air volume flow is at least as large as the supply air volume flow even if the space 10 is suddenly supplied inert gas and the exhaust system as such is not designed to dissipate a sufficiently large volume of exhaust air flow from the room atmosphere.

The mode of operation of the pressure relief or pressure compensation realized in the solution according to the invention is described in US Pat Fig. 3 shown flowchart again shown schematically.

The pressure relief or pressure compensation in the interior of the space 10 is initiated as soon as gaseous extinguishing agent is introduced from the inert gas source 11a into the protected area (step S1). Subsequently, with the aid of the pressure measuring device 15, the room pressure p _x in the interior of the room 10 is detected and the detected pressure value is fed to the controller 14 (step S 2). Subsequently, the controller 14 determines whether the detected pressure value p _{x reaches} a maximum limit value p _max , which is freely definable and preferably stored in a memory of the controller (step S3). If this is not the case (NO), the flow chart returns to the second process step (step S2) in which the instantaneous pressure P _x in the interior of the room is detected 10th

If, on the other hand, it is determined in method step S3 that the detected pressure value p _{x reaches} the predefined limit value p _max (YES), a suitable control signal is output by the controller 14 to the negative pressure generator 13 (step S 4). The negative pressure generating device 13 carries as long as exhaust air from the room atmosphere of the enclosed space 10 until the room pressure p _x again assumes a value below the predetermined limit value p _max (steps S5 to S7).

As already described, the negative pressure generating device 13 may be embodied either in the form of an exhaust air system which has a suction device 13a with which exhaust air is discharged in a controlled manner from the (gaseous) room atmosphere and out of the room volume. However, it is also conceivable for the vacuum generating device 13 to have a compressor 19 in order to compress the exhaust air volume to be discharged from the room atmosphere for the pressure compensation and thus to provide a pressure relief.

Although in the Fig. 1 and 2 not shown, it may be necessary that a filter device is provided in the exhaust pipe system 13b to clean or treat the exhaust air discharged from the room atmosphere and from the volume accordingly, before they either fed again as supply air to the room atmosphere or as Exhaust air is discharged from the outside atmosphere.

The solution according to the invention is not limited to fire extinguishing systems which provide a measure for fire suppression only in the case of a fire by sudden introduction of a quenching gas into the enclosed space 10. Rather, it is also conceivable to use the solution according to the invention, for example, in a so-called two-stage inerting system, as described for example in the German patent application DE 198 11 851 A1 is described.

In such a case, it is preferable that the used extinguishing agent is an inert gas or an inert gas mixture whose fire suppression or fire extinction is based on the so-called sting effect.

Moreover, it is advantageous if the device further comprises an oxygen measuring device 19 for detecting the oxygen content in the room atmosphere of the enclosed space 10. This oxygen measuring device 19 is - as well as the device 16 for detecting at least one fire parameter - preferably designed as aspirative operating system. To realize the device 16 for detecting a fire characteristic and for the realization of the oxygen measuring device 19, it would be conceivable to use one and the same aspiratively operating system, in which case in addition to the fire characteristic sensor in the detection chamber of the system, an oxygen sensor or detector for detecting the Oxygen content in the spatial atmosphere of the enclosed space 10 is arranged.

If the solution according to the invention is used in a one-stage or multi-stage inerting system, it is preferred that the inert gas source has an inert gas generation system 11b ', 11b "in addition to the glass bottle battery 11a (cf. Fig. 1 ). The inert gas generation system 11b ', 11b "comprises an ambient air compressor 11b" and an inert gas generator 11b' connected thereto. The controller 14 should be designed to control the air delivery rate of the ambient air compressor 11b "via appropriate control signals., In this way, the amount of inert gas provided by the inert gas system 11b ', 11b" per unit time can be determined by the controller 14.

The inert gas provided by the inert gas system 11b ', 11b "is supplied in a controlled manner via the supply pipe system 17a to the space 10 to be monitored, but it is of course also possible to connect a plurality of protective spaces to the supply pipe system 17a Inertgases via the outlet nozzles 17 b, which are arranged at a suitable location in the interior of the space 10.

In this further development of the solution according to the invention, the inert gas, advantageously nitrogen, is recovered locally from the ambient air. The inert gas generator or nitrogen generator 11b 'functions, for example, according to the known from the prior art membrane or PSA technology to produce a nitrogen-enriched air with, for example, 90 vol .-% to 95 vol .-% nitrogen content. This nitrogen-enriched air serves as an inert gas, which is supplied to the space 10 via the supply pipe system 17a. The enriched in the production of inert gas oxygen-enriched air is discharged via another pipe system to the outside.

Specifically, it would be conceivable that the controller 14 depending on an input into the controller 14 inerting the inert gas 11b ', 11b "controls so that the provided and introduced into the space 10 inert gas assumes a value for setting and / or The desired inertization level on the controller 14 can be selected, for example, by a key switch or password-protected on a control unit (not explicitly shown) according to a predetermined event sequence.

The solution according to the invention is not limited to the embodiments shown by way of example in the figures. Rather, variations of the described features are conceivable, as they are mentioned in the accompanying claims.

In particular, it is conceivable not to use a gas cylinder battery outside the enclosed space 10 as the inert gas source 11, but to provide a high-pressure pipe in the enclosed space 10. In this high pressure tube, at least a portion of the provided extinguishing agent should be stored under high pressure. Furthermore, the high-pressure pipe should have at least one exhaust valve that can be controlled by the controller 14 and belongs to the extinguishing agent supply device 17.

Claims (13)

1. An inerting method for preventing fire and for extinguishing fire in an enclosed room (10), particularly a laboratory, wherein fresh air is fed into the atmosphere of the room in regulated manner as supply air and exhaust air is discharged from the atmosphere of the room in regulated manner, and wherein in the event of a fire or to prevent a fire, an extinguishing agent which is gaseous under normal conditions is fed into the atmosphere of the room as the supply air, wherein a reduced room pressure (p_x) compared to the normal atmospheric pressure is set and/or maintained in the room (10) by the total volumetric flow of the supply air fed to the atmosphere of the room as fresh air and/or as extinguishing agent being at all times less than or equal to the volumetric flow of exhaust air discharged from the room's atmosphere,
   wherein the difference between the pressure prevailing in the room and the air pressure of the ambient air is determined continuously or at predefinable times and/or upon predefinable events and compared to a predefinable value, and wherein the total volumetric flow of supply air fed to the atmosphere of the room as fresh air and/or extinguishing agent as well as the volumetric flow of exhaust air discharged from the room's atmosphere is regulated as a function of said comparison, wherein the total volumetric flow of supply air fed to the atmosphere of the room as fresh air and/or extinguishing agent is equal to the volumetric flow of exhaust air discharged from the room's atmosphere when the difference determined between the room pressure (p_x) and the air pressure of the ambient air corresponds to the predefined value,
   characterized in that
   the respective volumetric flows of the fresh air fed in as supply air, the discharged exhaust air and the extinguishing agent fed in as supply air in the event of a fire or to prevent a fire are measured, and that the respective volumetric flows are regulated such that the difference between the total volumetric flow of the supply air fed into the room's atmosphere as fresh air and/or as extinguishing agent as well as the volumetric flow of the exhaust air discharged from the room's atmosphere assumes a constant predefinable value at all times,
   wherein the room (10) has a gas-tight and aerosol-tight structural shell, and wherein the constant predefinable value is preferably zero; and that in the case of extinguishing agent being supplied as the supply air, at least a portion of the exhaust air to be discharged from the room's atmosphere is compressed by means of a compressor (19) arranged inside the enclosed room (10), wherein the intake volume of the compressor (19) is greater than or equal to the total volumetric flow of the fresh air and/or extinguishing agent fed into the room's atmosphere as supply air, and wherein the exhaust air discharged from the atmosphere of the room and compressed by the compressor (19) is preferably temporarily stored in compressed form in a high-pressure storage tank (2) arranged inside the enclosed room (10).
2. The method according to claim 1, wherein at least a portion of the exhaust air compressed by the compressor (19) is discharged to the outside following treatment, particularly filtering or sterilizing.
3. The method according to one of the preceding claims, wherein the total volumetric flow of the supply air fed to the atmosphere of the room as fresh air and/or extinguishing agent is less than the volumetric flow of exhaust air discharged from the room's atmosphere when the difference determined between the room pressure (p_x) and the air pressure of the ambient air is less than the predefined value.
4. The method according to any one of the preceding claims, wherein the difference between the room pressure (p_x) and the air pressure of the ambient air is determined by measuring the pressure (p_x) in the room and the air pressure of the ambient air.
5. The method according to any one of the preceding claims, wherein at least one fire characteristic is measured in the atmosphere of the room continuously or at predefinable times and/or upon predefinable events, and whereby upon a fire characteristic being detected, the extinguishing agent is fed into the room atmosphere as supply air; and
   whereby upon a fire characteristic being detected, the fresh air normally supplied as the supply air is preferably discontinued or whereby the volumetric flow of the extinguishing agent fed into the room atmosphere in the event of a fire characteristic being detected is greater than the volumetric flow of the fresh air normally supplied to the room atmosphere.
6. The method according to any one of the preceding claims, wherein to prevent fire, both fresh air as well as extinguishing agent is fed into the room's atmosphere as supply air.
7. The method according to claim 6, wherein the concentration of extinguishing agent in the room's atmosphere is determined continuously or at predefinable times and/or upon predefinable events, and whereby the volumetric flow of the extinguishing agent fed into the room's atmosphere for the purpose of preventing fire is regulated as a function of the extinguishing agent concentration as determined such that a predefinable extinguishing agent concentration can be set and/or maintained in the room's atmosphere; and whereby the extinguishing agent is preferably an inert gas or an inert gas mixture, and whereby the extinguishing agent concentration in the room's atmosphere is preferably determined indirectly by measuring the oxygen content.
8. The method according to claim 7, wherein the volumetric flow of an inert gas or inert gas mixture supplied to the room's atmosphere for the purpose of preventing fire is regulated such that a base inertization level, which is higher than the characteristic reignition prevention level for the room (10), is set and maintained in the room's atmosphere, and whereby in the event of a fire, the volumetric flow of the inert gas or Inert gas mixture supplied to the room's atmosphere is regulated such that a full inertization level, which is equal to or lower than the characteristic reignition prevention level for the room (10), is set and maintained.
9. The method according to any one of the preceding claims, wherein the quality of the room's air is determined continuously or at predefinable times and/or upon predefinable events, and whereby the volumetric flow of the fresh air supplied to the room's atmosphere as supply air is regulated as a function of the quality of the air determined in the room; and
   whereby the quality of the room's air is preferably indirectly determined by measuring the CO_Z2content in the room's atmosphere.
10. The method according to any one of the preceding claims, wherein at least a portion of the exhaust air discharged from the room's atmosphere is refed back into the room's atmosphere as fresh air after being treated.
11. A device for realizing the method according to any one of claims 1 to 10,
    wherein the device comprises at least one mechanism (11) for providing an extinguishing agent which is gaseous under normal conditions and for immediately introducing the gaseous extinguishing agent into the room atmosphere of the enclosed room (10) when it has been determined that a fire has broken out in said enclosed room (10),
    wherein the device comprises a pressure relief mechanism (12) having a negative-pressure generating means (13) and a controller (14), wherein the controller (14) is designed to control the negative-pressure generating means (13) as a function of the pressure (p_x) prevailing in the atmosphere of the enclosed room (10) such that the pressure (p_x) prevailing in the room's atmosphere does not exceed a predefinable maximum pressure value (p_max), and
    wherein the device further comprises a pressure measuring mechanism (15) for measuring the physical pressure of the gas within the room's atmosphere, wherein the pressure measuring mechanism (15) is designed to measure the momentarily current room pressure (p_x) continuously or at predefined times and/or upon predefined events and feed said measured values to the controller (14), wherein the controller (14) is designed to accordingly control the negative-pressure generating means (13) based on the current pressure value (p_x), characterized in that
    the negative-pressure generating means (13) comprises a compressor (19) for compressing at least a portion of the exhaust air to be discharged from the room atmosphere and a high-pressure storage tank (20) for temporarily storing the exhaust air compressed by the compressor (19), and that a fire detection mechanism (16) is provided to detect at least one fire characteristic in the room's atmosphere continuously or at predefinable times and/or upon predefinable events and send the corresponding signals to the controller (14), wherein the controller (14) is designed to control an extinguishing agent feeding mechanism (17) such that in the event of a fire characteristic being detected, the extinguishing agent is fed into the room's atmosphere as supply air, wherein the compressor (19) and the high-pressure storage tank (20) are arranged inside the enclosed room (10).
12. The device according to claim 11, wherein the controller (14) is further designed to control the negative-pressure generating means (13) as a function of the pressure (p_x) prevailing in the atmosphere of the enclosed room (10) such that the room pressure (p_x) prevailing in the room's atmosphere does not fall below a predefinable minimum pressure value (p_min).
13. The device according to claim 11 or 12, wherein the controller (14) controls the compressor (19) such that the intake volume of the compressor (19) is greater than or equal to the total volumetric flow of the fresh air and/or extinguishing agent fed into the room's atmosphere as supply air.

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