METHOD FOR EXTINGUISHING A FIRE IN AN ENCLOSED SPACE, AND FIRE EXTINGUISHING SYSTEM

• US 20140345885A1
• Filed: 10/16/2012
• Published: 11/27/2014
• Est. Priority Date: 12/05/2011
• Status: Active Grant

• Current Assignee: Amrona AG
• Original Assignee: Amrona AG
• Inventors: Wagner, Ernst-Werner
• Granted Patent: US 9,707,423 B2
• Time in Patent Office: Days
• US Class Current: 169/46
• CPC Class Codes: A62C 3/002 for warehouses, storage areas or other installations for storing goods
• CPC Class Codes: A62C 35/68 Details, e.g. of pipes or valve systems valves in general F16K
• CPC Class Codes: A62C 37/04 with electrically-controlled release
• CPC Class Codes: A62C 99/0018 using gases or vapours that do not support combustion, e.g. steam, carbon dioxide

Abstract

The present invention relates to a system as well as a method for extinguishing fire in an enclosed room (6) in which the enclosed room (6) is flooded with extinguishing gas at least until an extinguishing gas concentration capable of providing an extinguishing effect (a) is set in the flood zone. In order to achieve the realizing of a maximum extinguishing gas concentration (b) as quickly as possible without the flooding of the room (6) thereby posing a danger to people, it is inventively provided for the flooding of the enclosed room (6) to be divided into a pre-flooding phase and a main flooding phase subsequent thereto. The pre-flooding phase corresponds to an interval of time between the time (t₁) the alarming starts to warn people of impending danger and a predefined time (t₂). The main flooding phase corresponds to an interval of time between the predefined time (t₂) and the time (t₄) at which a maximum extinguishing gas concentration (b) is reached. The enclosed room (6) is flooded such that during the entire pre-flooding phase, the concentration of extinguishing gas in the enclosed room (6) does not exceed a predefined or predefinable value for the extinguishing gas employed which is below the critical NOAEL value.

Claims

1-20. -20. (canceled)

21. A method for extinguishing fire in an enclosed room, wherein the method comprises the following procedural steps:

i) triggering a visual and/or acoustic alarm mechanism to warn any persons who might be within the enclosed room;

ii) initiating a release of extinguishing agent such that the enclosed room will be supplied an extinguishing gas until an extinguishing gas concentration capable of providing an extinguishing effect is set,

iii) monitoring the status of the enclosed room,

wherein the flooding of the enclosed room is divided into a pre-flooding phase and a main flooding phase subsequent thereto, wherein the pre-flooding phase corresponds to an interval of time between the time the alarm starts and a predefined time and the main flooding phase corresponds to an interval of time between the predefined time and the time at which a maximum extinguishing gas concentration is reached, and wherein the enclosed room is flooded such that the concentration of extinguishing gas in the enclosed room over the entire pre-flooding phase does not exceed a predefined or predefinable value for the extinguishing gas employed which is below the critical NOAEL value for the extinguishing gas as employed,

wherein the predefined time is selected such that any persons who may be within the enclosed room can exit said enclosed room during the pre-flooding phase,

wherein the extinguishing gas concentration in the enclosed room is maintained at the predefined or definable value after the pre-flooding phase ends during a first sustained flooding phase, wherein the first sustained flooding phase corresponds to an interval of time between the time at which the pre-flooding phase ends and a predefined time or manually definable time, and

wherein the first sustained flooding phase then only ensues when it can be verified automatically, particularly by means of at least one fire detector, and/or manually, particularly by actuation of a corresponding switch, that no fire is present in the enclosed room after the pre-flooding phase ends.

22. The method according to claim 21,

wherein the predefinable value is selected such that the pre-flooding phase is at least 10 seconds

23. The method according to claim 21,

wherein the enclosed room is flooded in procedural step ii) such that, at the latest at time, the extinguishing gas concentration in the enclosed room is at a predefined or definable value which is dependent on the fire load of the enclosed room.

24. The method according to claim 21,

wherein the time at which the extinguishing agent is released in procedural step ii) coincides with the time at which the visual and/or acoustic alarm mechanism is triggered in procedural step i).

25. The method according to claim 21,

wherein the following procedural step is provided after the main flooding phase ends:

maintaining the extinguishing gas concentration in the enclosed room such that during a second sustained flooding phase, the extinguishing gas concentration does not fall below the extinguishing gas concentration capable of providing an extinguishing effect dependent on the fire load of the enclosed room, wherein the second sustained flooding phase corresponds to an interval of time between the time at which the main flooding phase ends and a predefined time or manually definable time.

26. The method according to claim 21,

wherein the predefined or predefinable value for the concentration of extinguishing gas with respect to the extinguishing gas employed corresponds to an oxygen concentration which still allows unrestricted personnel accessibility to enclosed room.

27. The method according to claim 21,

wherein the enclosed room is monitored preferably continuously or at predetermined times or upon predetermined events with respect to the presence of at least one fire characteristic, and wherein procedural steps i) to iii) are preferably automatically initiated as soon as at least one fire characteristic is detected.

28. The method according to claim 21,

wherein the flooding of the enclosed room during the pre-flooding phase can be interrupted for a predefined period or completely stopped by the actuating of a stop or emergency stop button.

35. The method according to claim 22,

wherein the enclosed room is flooded in procedural step ii) such that, at the latest at time, the extinguishing gas concentration in the enclosed room is at a predefined or definable value which is dependent on the fire load of the enclosed room.

36. The method according to claim 23,

wherein the time at which the extinguishing agent is released in procedural step ii) coincides with the time at which the visual and/or acoustic alarm mechanism is triggered in procedural step i).

29. A fire extinguishing system for extinguishing fire in an enclosed room by flooding the enclosed room with an extinguishing gas in regulated manner, wherein the fire extinguishing system comprises the following:

at least one extinguishing gas source for supplying an extinguishing gas;

an extinguishing gas supply pipeline system by means of which the extinguishing gas provided by the at least one extinguishing gas source can be supplied to the enclosed room; and

a control unit for setting the amount of extinguishing gas supplied to the enclosed room per unit of time,

characterized in that

the control unit is designed to adjust the amount of extinguishing gas supplied to the enclosed room per unit of time in the event of fire or upon a manual actuation such that the enclosed room is flooded according to a predefined sequence of events, wherein during a pre-flooding phase lasting from an initial point in time up to a predefined point in time, the enclosed room is flooded such that the concentration of extinguishing gas in the enclosed room does not exceed a predefined or predefinable value for the extinguishing gas employed which is lower than the critical NOAEL value for the extinguishing gas employed, and wherein during a main flooding phase subsequent to the pre-flooding phase, the enclosed room is flooded such that the concentration of extinguishing gas reaches a target concentration which is equal to or greater than an extinguishing gas concentration dependent on the fire load of the enclosed room,

wherein the predefined time is selected such that any persons who may be within the enclosed room can exit said enclosed room during the pre-flooding phase, and preferably selected such that the pre-flooding phase is at least 10 seconds.

wherein a monitoring device is further provided to monitor the status of the enclosed room prior to the start of the main flooding phase, wherein the control unit is designed to only initiate the main flooding phase when the monitoring indicates that a fire in the enclosed room has not yet been extinguished or not completely extinguished, or when same is manually specified.

30. The fire extinguishing system according to claim 29,

wherein a visual and/or acoustic alarm mechanism is further provided to warn any persons who might be within the enclosed room, wherein the control unit is designed to initiate the release of extinguishing gas immediately upon the triggering of the alarm mechanism.

31. The fire extinguishing system according to claim 29,

wherein at least one sensor is further provided to detect at least one fire characteristic in the spatial atmosphere of the enclosed room, wherein the control unit is designed to initiate the flooding of the enclosed room as soon as at least one fire characteristic is detected in the spatial atmosphere of the enclosed room;

and/or

wherein at least one sensor is further provided to detect the oxygen content in the ambient air of the enclosed room, wherein the control unit is designed to set the amount of extinguishing gas supplied to the enclosed room per unit of time at least during the pre-flooding phase as a function of the detected oxygen content.

32. The fire extinguishing system according to claim 29,

wherein a first extinguishing gas source connectable to the enclosed room via a first triggering mechanism and a second extinguishing gas source connectable to the enclosed room via a second triggering mechanism are provided, and wherein the control unit is designed to trigger the first triggering mechanism at the start of the pre-flooding phase and to trigger the second triggering mechanism at the start of the main flooding phase.

33. The fire extinguishing system according to claim 29,

wherein an extinguishing gas source connectable to the enclosed room via a valve mechanism is provided, and wherein the control unit is designed to control the valve mechanism such that it is only partly open during the pre-flooding phase and completely open during the main flooding phase;

or

wherein an extinguishing gas generator connected or connectable to the enclosed room and a further extinguishing gas source connectable to the enclosed room via a valve mechanism are provided, and wherein the control unit is designed to activate the extinguishing gas generator during the pre-flooding phase and actuate the valve mechanism of the further extinguishing gas source during the main flooding phase.

34. The fire extinguishing system according to claim 29,

wherein a stop or an emergency stop button is provide which is connected to the control unit such that the flooding of the enclosed room during the pre-flooding phase will be interrupted for a predefined period of time or completely stopped when said stop or emergency stop button is actuated.