System and an arrangement to determine the level of hazard in a hazardous situation

• US 20030058103A1
• Filed: 10/24/2002
• Published: 03/27/2003
• Est. Priority Date: 03/28/2000
• Status: Active Grant

• Current Assignee: Firefly AB
• Original Assignee: Firefly AB
• Inventors: Jansson, Lennart Karl Erik
• Granted Patent: US 6,867,700 B2
• Time in Patent Office: Days
• US Class Current: 340/540
• CPC Class Codes: G08B 17/00 Fire alarms; Alarms responsive to explosion

Abstract

The present invention relates to a system and to an arrangement for evaluating in a defined space or area a delimited area (7) in which there is a degree of urgency greater than the degree of urgency in respect of the remainder of said space (1), wherein there is disposed within said space or area (1) a plurality of sensors which can evaluate the momentary degree of urgency on the basis of one or more criteria. Selected sensors (2, 3, 4) shall be connected to computer equipment (50) which includes storage elements (52, 53, 54) adapted for storing momentary criteria-related values in a chosen time order, and wherein a calculating circuit (51) included in or connected to said computer equipment (50) is adapted for evaluation of a calculated degree of urgency on the basis of time-dependent changes in the evaluated momentary values.

Claims

1. A system for evaluating the development of a hazard situation within a space or an area with the aid of hazard level concepts and, upon the occurrence of a hazard situation, creating conditions whereby the hazard level of the hazard situation can be obtained on the basis of information relating to the development of said hazard situation deriving from a plurality of sensors that function in respect of mutually the same or mutually different criteria, characterised in that information relating to the time-wise variation of output signals related to the hazard situation and obtained from a first sensor and also relating to the time-wise variation of similar output signals obtained from a second sensor can be stored;

in that a comparison between the momentary values of the output signals and/or measured time-related changes generate a hazard level value for the occurring hazard situation through the medium of a calculating circuit; and

in that solely the hazard level values that exceed a first hazard level of an indicated hazard situation are chosen to follow the development of the hazard situation by means of the output signals from said sensors.

2. A system according to claim 1, characterised in that said calculated hazard level value shall be chosen to exceed a first hazard level and to lie beneath a second hazard level.

3. A system according to claim 1 or 2, characterised in that when said calculated hazard level value exceeds a second hazard level and lies beneath a third hazard level, the development of the hazard and/or the event is further evaluated and one or more measures is/are taken from a plurality of available measures on the basis of this evaluation.

4. A system according to claim 1 or 2, characterised in that when said calculated hazard level value exceeds a highest value of a third hazard level one or more actions is/are taken from a number of available actions.

5. A system according to claims 1 to 4, characterised in that the threshold values of said hazard levels are adapted in respect of chosen criteria and/or a chosen combination of criteria.

6. A system according to claim 1 or 5, characterised in that a calculated hazard level is dependent on a significant change in the variation of the output signal of the first sensor in respect of the hazard situation, a significant change in the variation of the output signal of the second sensor in respect of the same hazard situation, the time duration between said significant changes, and the distance between used sensors.

7. A system according to claim 1, characterised in that the time-wise variation of each output signal in a first hazard level is inhibited, while each time-wise significant change in a second hazard level and above said first hazard level is registered and monitored or supervised to allow the development of the event or the hazard situation to be determined.

8. A system according to claim 1, characterised in that the threshold values of said hazard levels can be adjusted inversely to a value of the first time derivative of the variation.

9. A system according to claim 1 or 8, characterised in that the threshold values of said hazard levels can be adjusted to the choice of sensor-detecting criterion and/or sensor-associated environments.

10. A system according to claim 1, characterised in that one criterion is the value or magnitude of the air flow in a space with respect to the speed and/or direction of said air flow and/or a temperature-detecting sensor.

11. A system according to claim 1, characterised in that said sensors are adapted to evaluate the concentration of airborne gases, such as CO, CO₂ and/or other gases.

12. A system according to any one of the preceding claims, characterised in that selected sensors shall be connected to a control unit, such as computer equipment;

in that said control unit shall include and/or co-act with memory devices adapted for the storage of sensor-associated outputted criteria-related momentary values in a selected time order; and

in that the control unit includes and/or has connected thereto a calculating circuit which functions to allow a calculated hazard level value to be evaluated on the basis of time-dependent changes in the evaluated sensor-associated momentary values.

13. A system according to claim 12, characterised in that there is connected to said control unit at least one sensor which is adapted to evaluate the direction and speed of the air flow in said space.

14. A system according to claim 12 or 13, characterised in that there is connected to said control unit at least one sensor adapted for determining the presence of IR radiation.

15. A system according to claim 12, 13 or 14, characterised in that there is connected to said control unit at least one heat sensor or temperature indicator.

16. A system according to any one of the preceding claims, characterised in that said values are the subject of calculation with the use of priority-dependent and value-weighting means.

17. An arrangement for evaluating the development of a hazard situation within a space or within an area with the aid of hazard level concepts, and for creating in the event of an occurring hazard situation conditions which enable the hazard level of said hazard situation to be determined on the basis of information concerning the development of said hazard situation and obtained from a plurality of sensors in respect of mutually the same or mutually different criteria, characterised in that information obtained concerning the time-wise variation of the output signals related to said hazard situation and delivered from a first sensor and at least the time-wise variation of similar output signals from a second sensor are storable in the memory;

in that a comparison between the momentary values of said output signals and/or measured time-related changes generate through the medium of a calculated circuit a hazard level value for the occurring hazard situation; and

in that solely the values that exceed a first hazard level of an indicated hazard situation are chosen in following the development of the hazard situation with the aid of the sensor output signals.

18. An arrangement according to claim 17, characterised in that said calculated hazard level value can be chosen to exceed a first hazard level and to lie beneath a second hazard level.

19. An arrangement according to claim 17 or 18, characterised in that measures are taken to further evaluate the development of the hazard and/or the event when said calculated hazard level exceeds a second hazard level and lies beneath a third hazard level and one or more measures of a number of available measures is/are taken on the basis of this further evaluation.

20. An arrangement according to claim 17 or 18, characterised in that one or more actions of a number of available actions is/are taken when said hazard level value exceeds a highest value of a third hazard level.

21. An arrangement according to claims 17 to 18, characterised in that the threshold values of the hazard levels are adapted with respect to chosen criteria and/or a chosen combination of criteria.

22. An arrangement according to claim 17 or 18, characterised in that a calculated hazard level value consists in a significant change in the variation of the output signal from the first sensor caused by said hazard situation, and a significant change in the variation of the output signal of the second sensor caused by the same hazard situation, wherein said hazard level value can be evaluated with the aid of means that take into consideration the time duration between said significant changes and the distance between used sensors.

23. An arrangement according to claim 17, characterised in that each time-wise variation of the output signal in a first hazard level can be inhibited via means functioning to this end, while each time-wise significant change in a second hazard level that lies above said first hazard level can be registered and monitored in means functioning to this end, so as to enable the development of the event or hazard situation to be evaluated.

24. An arrangement according to claim 22, characterised by means for inverting the threshold values of said hazard levels to the value of the first time derivative of the variation.

25. An arrangement according to claim 17 or 24, characterised by means for adapting the threshold values of said hazard levels to the choice of sensor-detecting criteria and/or the sensor-associated environment.

26. An arrangement according to claim 17, characterised a further criterion is the momentary value of the speed and/or the direction of the air flow in said space and/or a temperature-detecting sensor.

27. An arrangement according to claim 17, characterised in that said sensors are adapted to evaluate the concentration of gases in the air, such as CO, CO₂ and/or other gases.

28. An arrangement according to any one of claims 17-27 inclusive, characterised in that said means include the connection of selected sensors to a control unit, such as computer equipment;

in that said control unit includes and/or co-acts with memory means adapted for the storage of sensor-associated momentary criteria-related values in a chosen time order; and

in that a calculating unit which is included in or connected to said control unit is adapted for the evaluation of a calculated hazard level value on the basis of time-dependent changes in the evaluated momentary values.

29. An arrangement according to claim 28, characterised in that at least one sensor adapted for determining the direction and speed of the air flow in said space is connected to said control unit.

30. An arrangement according to any one of claims 17-28 inclusive, characterised in that there is connected to said control unit at least one sensor adapted for evaluating IR radiation.

31. An arrangement according to claim 30, characterised in that each heat sensor or temperature indicator is connected to said control unit.

32. An arrangement according to any one of claims 17 to 31 inclusive, characterised, in that the calculating circuit includes priority-dependent and/or value-weighting means.