EP3568215B1

EP3568215B1 - A method for inerting a fire

Info

Publication number: EP3568215B1
Application number: EP18700992.3A
Authority: EP
Inventors: Torbjørn LAURSEN
Original assignee: Fire Eater AS
Current assignee: Fire Eater AS
Priority date: 2017-01-12
Filing date: 2018-01-12
Publication date: 2021-09-01
Anticipated expiration: 2038-01-12
Also published as: EP3568215A1; WO2018130644A1

Description

FIELD OF THE INVENTION

The present invention relates to the field of fire inerting. More particularly, it relates to the field of indoor fire inerting gas systems.

BACKGROUND OF THE INVENTION

In the field of indoor fire inerting gas systems, an inerting system is often installed to inert a fire in a specific room or a plurality of rooms. In the procedure of inerting the fire, an amount of inert gas is discharged into the room to reduce the percentage of oxygen in the air of the room. The reduced level of oxygen serves to inert the fire in the room. Certain types of inerting gasses allow people to breathe and function in the room with an oxygen level low enough to inert the fire. The inerting gasses themselves commonly do not contain oxygen but in conjunction with the remaining atmospheric air in the room, they may allow a person in the room to breathe.
In general, the gas system is provided as a first type or a second type of gas system. The first type is able to deliver inerting gas to a plurality of indoor locations from centrally stored containers whereas the second type is able to deliver inerting gas to a single indoor location from locally stored containers. As such each second type gas system includes at least a gas supply, a gas discharger and a sensor for sensing a fire. A second type gas system is presently advantageously installed if only one or a few rooms of a facility are to have a gas system installed. However, if the local system is later desired to be expanded to cover a plurality of rooms, there is presently no readily available way to expand the second type gas system or convert it into a first type gas system.
Relevant technology may be seen in US2011/253396 , US2008/196907 , EP1312392 , EP2404645 and US2274784 .

SUMMARY OF THE INVENTION

In a first aspect, the invention relates to a method according to claim 1.
In the present context, an indoor location is to be understood as any indoor location such as, e.g., a room of a building, a room or cargo compartment of a ship or plane, a construction or traffic tunnel or a garage.
The term fire inerting gas system should be understood as a system comprising a container or canister comprising a pressurized fire inerting gas and an outlet structure for release of an amount of the fire inerting gas in controlled manner. The outlet structure commonly comprises a conduit connecting the container or canister to an outlet arranged, e.g., within an indoor space. Release of the inerting gas may, e.g., be controlled by a valve which in turn may be controlled by a control system. The inerting gas system typically also comprises one or more detectors for detecting a fire and/or a condition indicative of the presence of a fire, such as increased temperature, or the presence of smoke and/or particles.
Thanks to the first and second communication modules configured for mutual communication, the first and second fire inerting gas systems are able to operate in a cooperative manner, which may improve operation and effectiveness of each of the first and second fire inerting gas systems. More particularly, by allowing the first and second fire inerting gas systems to communicate, they may operate as if they were one system able to deliver inerting gas to a plurality of indoor locations from centrally stored containers.
In embodiments, the first fire inerting gas system comprises at least one first container comprising a fire inerting gas, a first conduit connecting the at least one first container with an outlet at the first indoor location and a first control system, and the second fire inerting gas system comprises at least one second container comprising a fire inerting gas, a second conduit connecting the at least one second container and an outlet at the second indoor location and a second control system.
According to these embodiments, the first and second inerting gas systems are each allowed to be self-contained and be able to operate and be installed independently. Moreover, each of the first and second fire inerting gas systems may be installed independently and still be allowed to communicate and operate interdependently by virtue of the first and second communication modules.
In embodiments, no conduit extends between the first fire inerting gas system and the second indoor location, and wherein no conduit extends between the second fire inerting gas system and the first indoor location.
The first and second fire inerting gas systems do not require the possibly extensive infrastructure of the system with centrally stored containers. More particularly, the system with centrally stored containers commonly requires piping between the containers and each of the indoor locations. Such piping is not necessary in embodiments of present invention as each fire inerting gas are each allowed to comprise their own supply of fire inerting gas. Accordingly, present embodiments may ease instalment of a fire inerting gas system able to inert a fire at a plurality of indoor locations. They further allow an existing fire inerting gas system to be conveniently expanded by configuring the existing and the new system with communication capabilities as above. Further, present embodiments allow for a plurality of individual fire inerting gas systems to operate synergistically.
Generally, each of the first and second inerting gas systems are connected to the first and second communication modules in such a way that information received at the respective communication modules is used for controlling the release of inerting gas into the first and second indoor locations. Thus, release of gas at the first indoor location may be partially controlled on the basis of information received at the first communication module. Thus, information communicated to the first communication module from the second communication module regarding a condition at the second indoor location may be used to partially control the release of gas at the first indoor location. Likewise release of gas at the second indoor location may be partially controlled on the basis of information received at the second communication module, and information communicated to the second communication module from the first communication module regarding a condition at the first indoor location may be used to partially control the release of gas at the second indoor location
In one example, the detection of a fire condition at the first indoor location may be communicated via the first communication module to the second communication module, which in turn may cause the release of inerting gas at the second indoor location, even though a fire has not been detected at the second indoor location. Also, the development of a fire condition at one of the first and second locations, such as increasing or decreasing temperature or smoke intensity over time, may be communicated to the other one of the first and second indoor locations and used in control of the release of inerting gas.
In embodiments, each of the first and second fire inerting gas system comprises a respective first or second container containing a fire inerting gas.
In the present context, a concentration in percent by volume is referred to as a concentration in percent. Moreover, a concentration denoted as 9-13% is to be understood as a concentration being 9-13 percent by volume.
In embodiments, each of the first and second fire inerting gas systems are configured to be initiated by detection of a fire and/or signs of a fire such as, e.g., elevated temperatures, presence of flue gas, or other indicators of fire. When fire is detected, it is desirable to relatively quickly bring down the oxygen content from the common atmospheric concentration of oxygen at around 21% to a target concentration of oxygen at the indoor location in order to inert the fire. The target concentration of oxygen is preferentially around 8-14%, possibly 10-12%, and thereby low enough to inert the fire and still high enough to allow people to breathe in appropriate circumstances. The target concentration of oxygen may be combined with a target concentration of carbon dioxide of 2-5% being higher than the usual concentration of carbon dioxide in atmospheric air of around 0.05%. Also, at initiation of the first period of time, the air expelled by the first inerting gas delivered into the indoor location does likely not contain any inerting gas. However, eventually part of the air expelled from the indoor location by the inerting gas will itself contain inerting gas and accordingly, to reach the target concentration of oxygen, the concentration of oxygen of the inerting gas is preferentially well below the target concentration of oxygen, preferentially the inerting gas is void of oxygen. This allows for bringing down the concentration of oxygen at the indoor location. Similarly, the concentration of carbon dioxide of the inerting gas is preferentially well above the target concentration of carbon dioxide. In embodiments, the concentration of carbon dioxide in the inerting gas is 4-12%. In one embodiment, the concentration of carbon dioxide in the inerting gas is 4-12%
In general, the concentration of oxygen and the concentration of carbon dioxide of the inerting gas may depend on the flooding factor. Moreover, the flooding factor is a factor commonly known in the field and is a measure of the volume of the inerting gas delivered into the indoor location divided by the volume of the open space of the indoor location. As such, the higher the flooding factor, the closer the concentration of oxygen and/or carbon dioxide in the first inerting gas should be to the target concentration(s).
In embodiments, the first fire inerting gas system is configured to deliver a first predetermined amount of inerting gas along the first conduit into the first indoor location, the first predetermined amount of inerting gas being determined based on the size of the first indoor location, and the second fire inerting gas system is configured to deliver a second predetermined amount of inerting gas along the second conduit into the second indoor location, the second predetermined amount of inerting gas being determined based on the size of the second indoor location.
In embodiments, the each of the first and second fire inerting gas systema comprises an interface for receiving input relating to the size of the indoor location and/or the predetermined amount of first inerting gas. This allows each system to be readily configured to deliver the predetermined amount of first inerting gas based on the size of the indoor location.
In present context, the term 'size' may be understood as volume or area.
The predetermined amounts of delivered inerting gas based on the size of the first or second indoor location allows for estimation of the concentrations of, e.g., oxygen obtained after delivery of the inerting gas. Such prediction allows for predetermining the amount of delivered inerting gas to achieve a breathable yet fire inerting concentration of oxygen at the first and second indoor location.
In embodiments, the first fire inerting gas system is configured to communicate with the second fire inerting gas system if the first fire inerting gas system detects a fire and/or signs of fire. Because, the second fire inerting gas system is then allowed to know if the first fire inerting gas system detects a fire and/or signs of fire, the second fire inerting gas system is allowed to react even before detecting a fire and/or signs of a fire. This may reduce the change of a fire spreading from the first indoor location to the second indoor location.
In embodiments, the second fire inerting gas system is configured to deliver gas to the second indoor location if the first inerting gas system detects a fire and/or signs of fire. This may further reduce the change of a fire spreading from the first indoor location to the second indoor location.
In embodiments, the stand alone detector comprises a detector communication module configured to communicate with at least one of the first and second communication modules. In one embodiment, the second fire inerting gas system is configured to deliver gas to the second indoor location based on input from at least one stand alone detector of the system.
According to these embodiments, the first and/or second fire inerting gas system is allowed to operate based on input from the detector. As the detector may detect and transmit real-time conditions, the fire inerting gas system(s) may be able to operate based on these real-time conditions and thus optimize performance.
Further, based on input from the at least one stand alone detector, the first and/or second fire inerting gas system is allowed to refrain from delivering inerting gas to the respective indoor location until the at least one detector detects a predetermined condition. This may enable saving fire inerting gas until a suitable time when there is a risk of the fire spreading between the first and second locations. Accordingly, present embodiments may increase effectiveness of the use of fire inerting gas and thus further reduce the risk of fire spreading.
At least one stand alone detector of the system may be configured to detect flue gas at an indoor location. The presence of flue gas at a given location is a sign of a flow of flue gas from at least one fire to the given location. Accordingly, detection of flue gas by a stand alone detector arranged to detect flue gas a location, e.g., between the first and second indoor locations may be a sign of fire spreading between the first and second indoor locations. The stand alone detector thus may allow the first and/or second fire inerting gas system to take precautious actions and deliver inerting gas to prevent the fire from spreading.
At least one stand alone detector of the system may be configured to detect a temperature and/or temperature change at an indoor location. A relatively high and/or rising temperature may be a sign of fire. Particularly, it may be a sign of a spreading or nearing fire. Accordingly, a stand alone detector configured to detect a temperature and/or temperature change at a location, e.g., between the first and second indoor locations may allow the first and/or second fire inerting gas systems to prevent the fire from spreading.
At least one stand alone detector of the system may be configured to detect a flow of air. The detected flow of air may be an indicator of the likely hood of a fire spreading between the first and second locations. Accordingly, the stand alone detector of the flow of air may prevent a fire from spreading.
At least one stand alone detector of the system may be configured to detect if a closable path leading to the first and/or second indoor location is closed or open. Accordingly, the first and second fire inerting gas systems are allowed to operate on the basis of the closed or open passage.
In embodiments, the second fire inerting gas system is configured to deliver gas to the second indoor location if both the first inerting gas system detects a fire and at least one stand alone detector detects that the closable path leading to the first and second indoor location is open. Accordingly, based on input from the at least one stand alone detector, the first and/or second fire inerting gas system refrains from delivering inerting gas to the respective indoor location until needed. Accordingly, present embodiments may increase effectiveness of the use of fire inerting gas and thus further reduce the risk of fire spreading.
In this case, the first and second fire inerting gas systems are allowed to operate interdependently, while at the same time being self-contained each comprising a container comprising fire inerting gas, a conduit between the container and respective indoor location and an individual control system. By virtue of the second fire inerting gas system delivering fire inerting gas to the second indoor location if the first fire inerting gas system detects a fire and the intermittent pathway is in an open state, a fire may be prevented from spreading from the first indoor location to the second indoor location. Further, this is achievable without the need for any conduit extending between the first container and the second indoor location or vice versa.
The stand alone detector may detect the open state of the intermittent pathway be detecting any of several conditions directly or indirectly indicative of the intermittent pathway being in an open state such as, e.g., flue gas being in or near the intermittent pathway, a flow of air in or near the intermittent pathway, a closable path forming part of the intermittent pathway being in an open or closed state.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described in further described with reference to the accompanying drawings, in which:

Figs. 1 and 3 illustrate first and third embodiments not according to the invention and
Figs. 2 and 4 illustrate respective second and fourth embodiments of a system according to the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

The system 100 shown in Figs. 1-4 is arranged to deliver fire inerting gas at first and second indoor locations, 102 and 202 respectively. The system comprises a first fire inerting gas system 104 at the first indoor location 102, and a second fire inerting gas systems 204 at the second indoor location 204. The first fire inerting gas system 104 comprises a first container 106 containing an amount of pressurized gas, and a first sensor 108 for detecting at least one condition indicative of the presence of a fire at the first indoor location 102. The first sensor 108 is arranged to communicate its output to a first communication module 110 of the first fire inerting gas system 104. The first communication module 110 is arranged to at least partially control the release of inerting gas from the first container 106 via first conduit 112 and first outlet 114 into the first indoor location 102.
As shown in Figs. 1-4, the second fire inerting gas system 204 comprises a second container 206 containing an amount of pressurized gas, and a second sensor 208 for detecting at least one condition indicative of the presence of a fire at the second indoor location 202. The second sensor 208 is arranged to communicate its output to a second communication module 210 of the second fire inerting gas system 204. The second communication module 210 is arranged to at least partially control the release of inerting gas from the second container 206 via second conduit 212 and second outlet 214 into the second indoor location 202.
The first and second communication modules 110, 210 are interconnected via communications link 300 in order to allow each respective one of the first and second fire inerting gas systems 104 and 204 to be controlled on the basis of information received from the communications module of the other one of the first and second fire inerting gas systems. In particular, release of gas from each one of the containers 106 and 206 of the first and second fire inerting gas systems 104 and 204 may thus be partially controlled on the basis of outputs of both of the sensors 108 and 208. Thus, for example the detection, by the second sensor 208, of the condition indicative of a fire at the second indoor location 202, may be communicated via the second communication module 210 to the first communication module 110, so as to allow partial control of the release of gas from the first container 106 on the basis of the condition detected by the second sensor 208.
In the embodiment shown in Figures 1 and 2, the first and second containers 106 and 206, and the first and second communication modules 110 and 210 are arranged externally of the first and second indoor locations 102 and 202. In the embodiments of Figures 3 and 4, the containers 106 and 206 as well as the first and second communication modules are arranged internally within the first and second indoor locations.
The embodiments of Figs. 2 and 4, according to the invention, further comprises a sensor 302 arranged at a door or window 304 interconnecting the first and second indoor locations 102 and 202, the sensor being configured to detect the open or closed status of the door or wind 304. The sensor is arranged to communicate its output signal to the first and second communication modules 110 and 210, whereby the release of fire inerting gas from the containers 106 and 206 may be partially controlled on the basis of the window or door status. For example, in the event of the detection of a condition of a fire at one of the sensors 108 or 208 and simultaneous detection of an open door or window status, the mass flow of fire inerting gas released from each of the containers 106 and 206 may controlled at an increased level, which is higher than the level at which the mass flow would be increased if the sensor 302 would have detected a closed status of the door or window 304.

Claims

A method for inerting a fire at a plurality of indoor locations, the method comprising the steps of:
- providing a first fire inerting gas system (104) configured to detect and inert a fire at a first indoor location (102), the first fire inerting gas system comprising at least one first container (106) comprising a fire inerting gas, a first conduit (112) connecting the at least one first container with an outlet (114) at the first indoor location and a first control system;

- providing a second fire inerting gas system (204) configured to detect and inert a fire at a second indoor location (202), the second fire inerting gas system comprising at least one second container comprising a fire inerting gas, a second conduit (212) connecting the at least one second container (206) and an outlet (214) at the second indoor location and a second control system;

- providing the first fire inerting gas system with a first communication module (110);

- providing the second fire inerting gas system with a second communication module (210),wherein the first and second communication modules are configured for mutual communication and

- providing a stand alone detector (302) for detecting a state of an intermittent pathway between the first indoor location and the second indoor location, the stand alone detector comprising a detector communication module;
characterised in that the second inerting gas system delivering fire inerting gas to the second indoor location if:
∘ the first fire inerting gas system detects a fire at the first indoor location; and

∘ the stand alone detector detects an open state of the intermittent pathway.
A method for inerting a fire according to claim 1, wherein no conduit extends between the first fire inerting gas system (104) and the second indoor location (202), and wherein no conduit extends between the second fire inerting gas system (204) and the first indoor location (102).
A method for inerting a fire according to claim 1 or 2, wherein the stand alone detector (302) detects an open state of the intermittent pathway by detecting flue gas being in or near the intermittent pathway.
A method for inerting a fire according to any of the preceding claims, wherein the stand alone detector (302) detects an open state of the intermittent pathway by detecting a flow of air in or near the intermittent pathway.
A method for inerting a fire according to any of the preceding claims, the stand alone detector (302) detects an open state of the intermittent pathway by detecting on open state of a closable path (304) forming part of the intermittent pathway.
A method for inerting a fire according to any of the preceding claims, wherein the concentration of carbon dioxide in the inerting gas is 4-12%.
A method according to any of the preceding claims, wherein the concentration of oxygen in the inerting gas is configured to arrive at a target oxygen concentration, in the first and second indoor locations, of 8-14%.
A method according to claim 7, wherein the inerting gas is void of oxygen.
A method according to any of the preceding claims, wherein the first fire inerting gas system (104) is configured to deliver a first predetermined amount of inerting gas along the first conduit (112) into the first indoor location, the first predetermined amount of inerting gas being determined based on the size of the first indoor location (102), and the second fire inerting gas system (204) is configured to deliver a second predetermined amount of inerting gas along the second conduit (212) into the second indoor location (202), the second predetermined amount of inerting gas being determined based on the size of the second indoor location (202).
A method according to any of the preceding claims, wherein the first and second fire inerting gas (104, 204) comprises an interface for receiving input relating to the size of the indoor location (102, 202) and/or the predetermined amount of first inerting gas.