Method and system for providing emergency call service

• US 5,379,337 A
• Filed: 08/16/1991
• Issued: 01/03/1995
• Est. Priority Date: 08/16/1991
• Status: Expired due to Term

• Current Assignee: Qwest Communications International Incorporated (Lumen Technologies, Inc.)
• Original Assignee: U.S. West Advanced Technologies, Inc.
• Inventors: Rice, John R., Nelson, Michael J., Castillo, Michael J., Neal, Lisa M.
• Primary Examiner(s): Chan, Wing F.
• Application Number:
  US07/747,151
• Time in Patent Office: 1,236 Days
• Field of Search: 379/39, 379/42-45, 379/46, 379/47, 379/49, 379/201, 379/207, 379/210, 379/212, 379/206, 379/219, 379/220, 379/221, 379/266
• US Class Current: 379/45
• CPC Class Codes: H04M 11/04 with alarm systems, e.g. fire, police or burglar alarm systems

Abstract

An emergency call routing system includes a platform having a call router and a processor for identifying destinations to which such router directs emergency calls. The processor receives administration commands from administrators, some of which are at a public safety answering point (PSAP) to which the router directs calls for handling and redirection to emergency service providers (ESPs). Some of such administration commands relate to defining intervals during which a particular PSAP is, according to an administered night service schedule, to be inactive with respect to handling emergency calls. Other of such commands relate to administrative operations to place such PSAPs into such inactive state earlier than the schedule. Others of such commands relate to administrative directions to withdraw such PSAP from such inactive state before the scheduled time. Interfaces between attendants/administrators and workstations used with such processor are provided to facilitate ease of administering such schedule and those overrides.

Claims

1. A system for initializing operation of means for routing emergency calls to a selected means for answering calls, said answering means having an active condition and an inactive condition, said system comprising:

first means for determining whether said answering means should be in said inactive condition upon the initial operation of said routing means;

means effective upon said first determining means determining that said answering means should be in said inactive condition upon said initial operation of said routing means for causing said answering means to be in said inactive condition, said causing means comprising;

means for defining an interval of time during which said answering means is to be in said inactive condition;

second means for determining whether said particular time of initializing said routing means is within said interval of time; and

means effective upon a determination that said time of initializing is not within said interval of time for rendering said causing means effective to maintain said answering means in said inactive condition during said interval of time.

2. A system for initializing said operation according to claim 1, said causing means further compromising:

means for providing a signal to indicate the end of said inactive condition of said answering means.

3. A system according to claim 1, further comprising:

means effective upon said first determining means determining that said answering means should not be in said inactive condition upon said initial operation for causing a signal to occur to indicate the time at which said answering means is to enter said inactive condition.

4. A system according to claim 1, wherein said initializing occurs at a particular time, said causing means further comprising:

means for defining a night service interval of time during which said answering means is in said inactive condition;

means for overriding said causing means, said overriding means having a disabled condition and an override condition, in said override condition said overriding means causing said ansering means to selectively be in said active condition or in said inactive condition;

second means for determining if said particular time of initializing is within said night service interval; and

means effective upon a determination that said time of initializing is within said night service interval for causing said overriding means to be in said disabled condition and for rendering said defining means effective to indicate the end of said night service interval.

5. A system for administering the state of an emergency telephone call answering station adapted to be in an active state or an inactive state according to a plurality of schedules selected for controlling the availability of said station to answer said call, said schedules being administrable to provide a first schedule and a second schedule, a next one of said states temporally following a current one of said states according to one of said schedules, comprising:

means for administering said first schedule to either add to, modify or delete said first schedule to form said second schedule;

means for signalling the start and end of said inactive states, said signalling means being set to signal said inactive states which may be in said first schedule; and

means responsive to the addition to or modification of said first schedule for rendering said signalling means ineffective with respect to the start and end of said inactive states which may be in said first schedule.

6. A method for controlling emergency call routing from an incoming trunk to a selected one of a plurality of call answering stations;

each said station being adapted to be in one of an active state or a night service state;

said night service state being scheduled to occur during a night service interval of time;

said method utilizing a computer having a first table for selectively establishing for each said station an in early condition for overriding said active state, an out early condition for overriding said night service state, and a disabled condition for overriding neither said active nor said night service state;

said computer having a second table for indicating for each said station an active state and said night service state;

said computer being adapted to be initialized at given time;

said method comprising the steps of;

at said given time, checking said first table to see if one of said in early or out early override conditions is established for a selected one of said stations;

neither of said in early nor out early conditions is established at said given time for said selected station, comparing said given time to said night service interval for said selected station; and

if said given time is not within said night service interval causing a signal to occur at the time at which said night service interval is to start for said selected station and setting said second table to indicate that said selected station is in said active state.

7. A method accordint to claim 6, further comprising the steps of

if one of said in early or out early conditions exists at said given time then determining whether said in early condition exists;

and

if said in early condition exists and if none of said night service intervals is scheduled for said selected station then causing said second table to indicate that said station is said night service state.

8. A method according to claim 6, wherein said first table established said out early condition of said selected station at an override time;

said method further comprising the step of;

if one of said in early or out early conditions exists at said given time, then determining that said out early condition exists.

9. A method according to claim 8 further comprising the step of:

if said override time was in one of said night service intervals then determining whether said override time and said given time are within the same night service interval.

10. A method according to claim 9 further comprising the step of

if said override time and said given time are within the same night service interval, causing second table to indicate said active state for said selected station.

11. A method according to claim 8 further comprising the step of:

if said override time was not in one of said night service intervals then causing said first table to establish said disabled condition.

12. A method according to claim 8 further comprising the step of:

if said override time was not in one of said night service intervals then determining if said given time is in one of said night service intervals.

13. A method according to claim 8 further comprising the step of:

if said given time is in said night service interval, then causing said second table to indicate that said station is currently in said inactive state.

14. A method according to claim 13 further comprising the step of:

if said given time is not in said night service interval, then causing said second table to indicate that said station is currently in said active state.

15. A method for controlling the availability of a call answering station to answer an emergency call routed to it from an incoming trunk;

said station being adapted to be in one of an active state or a scheduled unavailable state;

said scheduled unavailable state being scheduled to occur during a scheduled unavailable interval of time, said method utilizing a computer having a first table for selectively establishing for each said station an in early condition for overriding said active state, an out early condition for overriding said scheduled unavailable state; and

a disabled condition for overriding neither said active nor said scheduled unavailable state;

said computer having a second table for selectively indicating for said station said active state and said scheduled unavailable state;

said computer being adapted to be initialized at a given time, said method comprising the steps of;

at said given time, checking said first table to see if one of said in early or out early override conditions is established for said station;

if neither of said in early nor out early conditions is established at said given time for said station, comparing said given time to said scheduled unavailable interval for said station; and

if said given time is not within said scheduled unavailable interval causing a signal to occur at the time at which scheduled unavailable interval is to start for said station and setting said second table to indicate that said station is available to answer said emergency call.

16. A method according to claim 15 further comprising the steps of:

if one of said in early or out early conditions exists at said given time then determining whether said in early condition exists; and

if said in early condition exists and if none of said scheduled unavailable intervals is scheduled for said selected station then causing said second table to indicate that said station is in said scheduled unavailable state.

17. A method according to claim 15, wherein said first table established said out early condition of said station at an override time, said method further comprising the step of:

if one of said in early or out early conditions exists at said given time, then determining that said out early condition exists.

18. A method according to claim 17 further comprising the step of:

if said override time was in one of said scheduled unavailable intervals then determining whether said override time and said given time are within the same scheduled unavailable interval.

19. A method according to claim 18 further comprising the step of:

if said override time and said given time are within the same scheduled unavailable interval, causing said second table to indicate said active state for said selected station.

20. A method according to claim 17 further comprising the step of:

if said override time was not in one of said scheduled unavailable intervals then causing said first table to establish said disabled condition.

21. A method according to claim 17 further comprising the step of:

if said override time was not in one of said scheduled unavailable intervals then determining if said given time is in one of said scheduled unavailable intervals.

22. A method according to claim 17 further comprising the step of:

if said given time is in said scheduled unavailable interval, then causing said second table to indicate that said station is currently in said scheduled unavailable state.

23. A method according to claim 17 further commprising the step of:

if said given time is not in said scheduled unavailable interval, then causing said second table to indicate that said station is currently in said active state.

24. A method according to claims 16 or 21, said station also being adapted to be in an unscheduled unavailable state said second table also selectively indicating said unscheduled unavailable state for said station, said method further comprising the step of:

causing said second table to indicate that said station is in said scheduled unavailable state only if said station is not in said scheduled unavailable state at said given time.

25. A system for administering the state of an emergency telephone call answering station adapted to be in an active state or an inactive state according to a plurality of schedules selected for controlling the availability of said station to answer said call, said schedule being administrable to provide a first schedule and a second schedule, a next one of said states temporally following a current one of said states according to one of said schedules, comprising:

means for administering said first schedule to either add to, modify or delete said first schedule to form said second schedule; and

first means responsive to the adding to or modifying of said first schedule to form said second schedule at a current time for determining whether said current time is within an inactive state of said second schedule.

26. A system according to claim 25, further comprising:

second means for ignoring said determination of said first means that said current time is within said inactive state of said second schedule and setting.

27. A system according to claim 26, further comprising:

means effective if said second means has not ignored said determination for rendering said station unavailable to answer said call.

28. In a system for controlling the availability for operation of a unit for answering an emergency telephone call, said unit being available for operation in an active service interval and not being available for operation in an inactive interval, the improvement comprising:

means for signalling a change in a current one of said intervals;

first means for determining whether the change in said current interval is the end or the start of one of said inactive intervals;

means for setting a record to indicate whether or not a particular unit is currently scheduled for an inactive interval; and

means for overriding said record to indicate a new availability of said unit changing from said inactive interval to said active interval or changing from said active interval to said inactive interval regardless of which of said intervals is currently scheduled as indicated by said record.

29. A system according to claim 28, further comprising:

second means responsive to said first determining means determining that said change in said current interval is the start of said inactive interval for determining that said unit is currently not in said inactive interval and that said overriding means has not overridden said record to change said availability to said inactive interval.

30. A system according to claim 29, further comprising:

means responsive to said second means making both of said determinations for causing said record setting means to set said record to indicate that said unit currently is scheduled for said inactive interval.

31. A system according to claim 28, further comprising:

means having an override record for recording said new availability of said unit;

said overriding means being effective to cause said override record to change from a first setting to a second setting for indicating said change to said active service interval or to said inactive interval; and

second means responsive to said determining means determining that said change is the start of said inactive interval for determining that said unit currently is in said inactive interval and that said override record is in said second setting for causing said signalling means to signal the end of said inactive interval.

32. A system according to claim 28, further comprising:

second means responsive to said first determining means determining that said change is the end of a current one of said inactive intervals for determining whether said overriding means set said record to indicate changing from said inactive interval to said active service interval.

33. A system according to claim 32, further comprising:

means responsive to said second means determining that said record is set to indicate changing to said active service interval for setting said signalling means to signal a change from said active service interval to said inactive interval.

34. A sytem according to claim 32, further comprising:

means responsive to said second means determining that said record is not set to indicate changing to said active service interval for causing said setting means to indicate that said particular unit is not currently scheduled for said inactive interval.

35. A system according to claim 28, further comprising:

means responsive to said first determining means for setting said signalling means to indicate the end or the start of said inactive interval.

36. A system according to claim 28, further comprising:

means having an override record for recording said new availability of said unit;

said overriding means being effective to cause said override record to change from a first settig to a second setting for indicating said change to said active service interval or to said inactive interval; and

second means responsive to said determining means determining that said change is the start of said inactive interval for determining that said unit currently is in said inactive interval and that said override record is in said second setting for changing said override record to said first setting.

37. A system for controlling the operation of a switching device that routes incoming emergency telephone calls to a public safety answering point at a current time, said switching device having router means for sending first messages related to one of said calls received by said switching device, and said router means having means for receiving return messages indicative of a particular PSAP to which said one call is to be routed, said switching device also having computer means for receiving said first messages and generating said return messages, said PSAP being adapted to be in an active service state to answer said calls routed thereto, during a given interval of time said PSAP being adapted to be in a night service state unavailable to answer saic calls, comprising:

first means for causing said computer means to define a schedule including at least one first interval of time corresponding to said active service state, said schedule including at least one night service interval of time corresponding to said night service state;

second means for causing said computer means to record conditions for overriding said scheduled intervals of time, said conditions including an in early condition and an out early condition;

third means for causing said computer means to signal a change in the service state of a given PSAP, said change being based on said schedule; and

fourth means for causing said computer means to determine whether said signal indicates the start or the end of said night service state.

38. A system according to claim 37, further comprising:

fifth means for causing said computer means to determine whether at the current time at which one said call is to be routed said given PSAP is in said night service state and whether one of said in early conditions is recorded by said second means.

39. A system according to claim 38, further comprising:

sixth means effective upon said fifth means determining that said given PSAP is in said night service state and that said in early condition is recorded by said second means for causing said computer means to set said third means to operate at the end of a current one of said night service intervals to signal the end of said current night service control.

40. A system according to claim 38, further comprising:

sixth means effective upon said fifth means determining that either said given PSAP is not in said night service state and/or that said in early condition is not recorded by said second means for causing said computer means to cause said PSAP to be in said night service state.

41. A system for changing the state of an emergency telephone call answering station adapted to be in an active state or an inactive state, a next one of said states temporally following a current one of said states, comprising:

first means for indicating the start of a next one of said inactive states;

second means for determining whether one or more of said emergency calls are enroute to said station when said state is to be changed to said next inactive state;

third means responsive to a determination that at least one of said emergency calls is enroute to said station for delaying said change in said state to said next inactive state for a selected period of time;

fourth means effective at the end of said period of time for rendering said second determining means effective; and

fifth means responsive to a determination by said second means that none of said emergency calls is enroute to said station for indicating that said station is in said next inactive state.

42. A system according to claim 41, further comprising:

means responsive to said first means for causing a record to be made to indicate that said station is in said next inactive state.

43. A system according to claim 41, wherein said station includes at least one workstation, each of said workstations having a display screen, said system further comprising:

means responsive to said operation of said delaying means for causing said display screens to display messages indicating that said station will soon change to said inactive state.

44. A system according to claim 41, wherein said station may additionally be in an abandoned condition, said system further comprising:

second means for determining whether said station is in said abandoned state; and

means effective when said station is in said abandoned state for rendering said first determining means inoperative so that the state of said station is not changed.

45. A system according to claim 41, wherein said station includes at least one workstation, each of said workstations having a display screen, said system further comprising:

means responsive to said determination that no emergency calls are enroute to said workstation for causing said display screens of said workstations to display on said screen a message indicating that said station is in said inactive state.

46. A system according to claim 45, wherein a first line is connected to said station for carrying emergency call notification messages to said station, and wherein a second line is connected to said station for carrying said emergency calls to said station, said system further comprising:

means responsive to said determination that none of said emergency calls is enroute to said station for preventing said emergency calls from being routed to said station.

47. A system for controlling to which of first and second telephone call answering stations a given incoming emergency call is to be routed, wherein said stations serve an emergency call region in which there is historically a relatively low number of emergency calls during a night service interval of time and historically a relatively greater number of emergency calls during an active service interval of time, and wherein a call router receives said incoming calls and directs each such call to a particular one of said stations, said system comprising:

means for establishing a schedule for each of said first and second stations, one of said schedules designating at least one of said active intervals for said first station, another of said schedules designating at least one of said active intervals for said second station, at least one of said schedules for said second of said stations also designating at least one of said night service intervals; and

means responsive to each of said schedules for controlling said router to route all of said incoming calls to said first of said stations during said night service interval designated for said second station.

48. A system according to claim 47, said establishing means further comprising:

a workstation for displaying a period of time having a plurality of increments;

means for selecting for said second station a first interval of time in said period as said night service interval and a second interval of time coincident with said first interval of time as said active service interval of time for said first station;

means for storing a record representing a state of each said first and second stations based on said respective active and night service intervals for said respective first and second stations, a night service state corresponding to said night service interval and an active state corresponding to said active interval; and

said controlling means comprising means responsive to said records for causing said router to route to said first station said emergency calls received during said night service interval.

49. A system according to claim 48, further comprising:

timing means for indicating the end of said interval, and

means responsive to an indication of the end of said first interval for changing said first record to indicate that said second station is available to answer emergency calls.

50. A system according to claim 48, further comprising:

second means for indicating the current time at which said given call is to be routed; and

first means for determining whether said current time is in said first interval.

51. A system according to claim 48, further comprising:

means responsive to the determination that said current time is in one of said night service intervals for updating said record for said second station to represent said night service state.

52. A system according to claim 48, wherein a current time is the time at which one said call is to be routed, further comprising:

means for determining that a current one of said first intervals should end; and

means responsive to said determining means for updating said record to represent said active state of said second station.

53. A system according to claim 52, further comprising:

said first determining means comprising flag means for recording an out early flag with respect to said first interval, and second means responsive to said out early flag for determining whether said current time is in said first interval; and

said updating means is responsive to said second determining means determining that said current time is in said interval for updating said record to indicate that said second station is in said active state.

54. A system according to claim 48 further comprising:

said storing means also storing a flag record representing a flag to end said active state before the scheduled start of said first interval; and

menas responsive to said selecting means selecting said flag for updating said flag record to render said station inactive before the start of said first interval.

55. A system according to claim 54, further comprising:

second means responsive to said selection of said flag for determining that the current time is before the start of said first interval; and

means for causing said timing means to be set for indicating the end of said first interval.

56. A system according to claim 48, further comprising:

said flag record also being adapted to represent a disabled flag having no effect on said active and inactive states;

said second means also being for determining that the current time is within said first interval; and

means responsive to said determination that the current time is within said first interval for updating said flag record to represent said disabled flag.

57. A system according to claim 48, further comprising:

said storing means comprising a database manager for updating said records following said selecting of said intervals; and

said router comprising a memory for storing a second record indicating that at a current time each said first and second station is either inactive or available to answer one of said emergency calls.

58. A system according to claim 57, wherein a plurality of said emergency call answering stations is connected to said router, further comprising:

said router being at a location different from the location of each of said stations and including said displaying means and said selecting means, each of said displaying means and said selecting means being selectively effective with respect to said stations to enable said first interval to be selected for said second station.

59. A system for controlling the availability for operation of a station for answering emergency telephone calls, said station having an inactive state and an active state, comprising:

means for establishing a schedule for said station, said schedule indicating when said station is to be in said active state and when in said inactive state; and

means for overriding said schedule to cause said station to be out early from said inactive state when said schedule indicates that said station is to be in said inactive state or to be in early to said inactive state when said schedule indicates that said station is to be in said active state.

60. A system according to claim 59, said means for overriding, further comprising:

in early means effective when said station is in said active state for causing said station to be in said inactive state.

61. A system according to claim 60, said in early means further comprising:

means for setting an in early flag;

means responsive to said in early flag for determining whether said station is currently in said inactive state; and

means effective when said station is currently in said active satat for causing said station to be in said inactive state.

62. A system according to claim 61, further comprising:

means effective when said station is currently in said inactive state for causing said setting means to set said flag to a disabled condition.

63. A system according to claim 59, further comprising:

said overriding means having a disabled condition in which it does not cause either of said overriding to occur;

means for recording said disabled condition;

means responsive to said overriding means not being set to cause said out early nor said in early overriding for recording said disabled condition of said overriding means.

64. A system according to claim 63, further comprising:

routing means responsive to said disabled condition of said overriding means for routing said telephone calls to said station when said station is in said active state according to said schedule.

65. A system according to claim 59, said means for overriding further comprising:

out early means when said station is in said inactive state for causing said station to be in said active state.

66. A system according to claim 65, said out early means further comprising:

means for setting an out early flag;

means responsive to said out early flag for determining whether said station is currently in said inactive state; and

means effective when said station is in said inactive state for causing said station to be in said active state.

67. A method utilizing a computer for controlling emergency call routing from an incoming trunk to a selected one of a plurality of call answering stations;

each said station being adapted to be in one of an active state, a night service state or an abandoned state;

said night service state being scheduled to occur during a night service interval of time;

said abandoned state being unscheduled;

said computer having a first table for selectively establishing for each said station an in early condition for overriding said active state, an out early condition for overriding said night service state; and

a disabled condition for overriding neither said active nor said night service state;

said computer having a second table for indicating for each said station an active state, said abandoned state and said night service state;

said computer being programmed to perform the following functions;

at an administration time, updating said first table for one of said stations to establish one of said out early condition, in early condition or disabled condition and getting said administration time;

if said established condition is said in early condition, and if said one station is not in said night service state at said administration time, then updating said second table for said one station to indicate that said one station is in said night service state.

68. A method according to claim 67, said computer being programmed to perform the following functions:

if said established condition is not said in early nor said disabled conditions, then determining if said second table indicates that said one station is in said night service state; and

if said second table indicates that said one station is not in said night service state, then setting said first table to establish said disabled condition for said one station.

69. A method according to claim 67, said computer being programmed to perform the following functions:

if said established condition is not said in early nor said disabled conditions, then determining if said second table indicates that said one station is in said night service state; and

if said second table indicates that said one station is in said night service state, then updating said second table for said one station to said active state.

70. A method according to claim 69, said computer being programmed to perform the following functions:

if said second table indicated said night service condition for said one station was not due to an in early condition established by said first table, then setting said first table to establish said out early condition.

71. A computer according to claim 69, said computer being programmed to perform the following functions:

if said second table indicated said night service condition for said one station due to an in early condition established by said first table, then settig said first table to establish said disabled condition.

72. A method according to claim 67, said computer being further programmed to perform the following functions:

if said established condition is said in early condition, and if said one station is in said night service state at said administration time, then setting said first table to establish said disabled condition for said one station.

73. In a computer system including a computer for rendering a public safety answering station available or not available to receive incoming emergency telephone calls, said system including table means for storing a plurality of records, said availability of said station being indicated by an active one of said records, said nonavailability of said station being indicated by a night service one of said records, or an abandoned one of said records, an availability schedule being provided to define at least one active interval of time during which said station is available, said schedule also defining a night service interval of time during which said station is not available, the improvement in said system comprising:

first means for causing said computer to store an in early override one of said records to render said active record ineffective;

second means for causing said computer to store an out early one of said records to render said night service record ineffective;

said first and second means being effective at an override time; and

third means for causing said computer to determine if, at a given time within said availability schedule, either said in early one or said out early one of said records is stored.

74. In the computer system according to claim 73, the further improvement comprising:

fourth means for causing said computer to determine if said given time is within said night service interval of time.

75. In the computer system according to claim 74, the further improvement comprising:

fifth means effective if said given time is not within said night service interval of time of said records to indicate that at said given time said station is available to receive incoming telephone calls.

76. In the computer system according to claim 74, the further improvement comprising:

sixth means effective if said given time is within said night service interval of time for causing said computer to store one of said records to indicate that at said given time said station is unavailable to receive incoming telephone calls.

77. In a system for controlling the availability for operation of a unit for answering an emergency telephone call, said unit being available for operation during one or more active service intervals and not being available for operation during one or more inactive intervals, the improvement comprising:

means for preparing a schedule for said unit wherein said schedule includes at least one of said active service intervals and/or at least one of said inactive intervals;

means for causing said preparing means to change said schedule from an original schedule to a new schedule; and

first means for determining whether the change in said schedule was a modification or an addition to or a deletion from said original schedule.

78. A system according to claim 77, further comprising:

means for signalling the start or the end of said inactive intervals, said signalling means initially being set to signal according to said original schedule and being responsive to an update to signal according to said new schedule;

means responsive to said first determining means determining that said change was an addition or modification to said schedule for canceling the operation of said signalling means according to said original schedule.

79. A system according to claim 78, wherein said original schedule was changed at a given time, further comprising:

second means for determining whether said given time is within said changed schedule.

80. A system according to claim 79, further comprising:

means for setting an override flag to render said current and changed schedules ineffective to schedule the availability of said unit to answer said call; and

third means effective at said given time for determining whether said override flag is set.

81. A system according to claim 80, further comprising:

means for setting said signalling means according to said changed schedule to signal the start of the next inactive interval.

82. A system according to claim 80, further comprising:

means responsive to said third means determining that said override flag is not set at said given time for invoking said inactive interval of said station.

83. The system according to claim 77, further comprising:

said means for preparing a schedule being unadministered when no schedule has been prepared for said unit; and

means responsive to said first means determining that said change in said schedule was to delete said schedule for indicating that said schedule is unadministered.

84. The system according to claim 77, further comprising:

means for recording said original and new schedules; and

means responsive to a determination that said change was a deletion for deleting said orignal schedule.

85. A system for controlling the availibility of an emergency call answering station to answer emergency calls, comprising:

means for displaying a period of time having a plurality of increments;

means for selecting an interval of time in said period as an interval;

during which said station is to be inactive;

means for storing a first record of at least one said interval for said station; and

means normally effective for routing said emergency calls to said station, said routing means being responsive to said first record for routing said calls received during said interval to a destination other than said station.

86. A system according to claim 85, further comprising:

said means for displaying comprising a workstation at said emergency call answering station;

said storing means comprising a database manager for updating said storing means following said selecting of said interval; and

said routing means comprising a memory for storing a second record indicating that at a current time said station is either inactive or available to answer one of said emergency calls.

87. A system according to claim 85, wherein a plurality of said emergency call answering stations are connected to said routing means, further comprising:

said routing means is at a location different from each of said stations and includes said displaying means and said selecting means, each of said displaying and selecting means being selectively effective with respect to one of said stations so that said interval is selected for said one station.

88. A system according to claim 85, further comprising:

said routing means further comprising timing means for indicating the end of said interval, and means responsive to an indication of the end of said interval for changing said first record to indicate that said station is available to answer emergency calls.

89. A system according to claim 88, further comprising:

means for indicating the current time at which a given one of said calls is to be routed; and

first means for determining whether the current time is in said interval.

90. A system according to claim 89, further comprising:

table means for recording a third record indicative of said station being inactive; and

means responsive to the determination that the current time is in one of said intervals for entering said third record in said table means.

91. A system according to claim 90, further comprising:

means for updating said third record to represent said active state of said station so that said routing means will route said calls to said station before the end of said interval.

92. A system according to claim 91, further comprising:

said updating means comprising flag means for recording an out early flag with respect to said interval, and means responsive to said out early flag for determining whether the current time is in said interval; and

means responsive to said first determining means determining that the current time is in said interval for causing said updating means to update said third record to indicate that said station is active.

93. A system according to claim 90, further comprising:

said table means being for recording a fourth record indicative of a flag to end said active state before the start of said interval; and

means for entering said fourth record in said table means to render said station inactive before the end of said interval.

94. A system according to claim 93, further comprising:

second means for determining that the current time is before the start of said interval; and

means for causing said timing means to be set for indicating the end of said interval.

95. A system for changing the state of an emergency telephone call answering station adapted to be in an active state or an inactive state, said inactive state having been scheduled or unscheduled, a next one of said states temporally following a current one of said states, comprising:

first means for indicating the end of a current one of said inactive scheduled states;

second means for determining whether said station is in one of said unscheduled inactive states;

means for recoding the current state of said station;

means responsive to said second means determining that said station is not in one of said unscheduled inactive states for causing said recording means to record the active state of said station; and

third means for determining whether said state is currently being changed to said inactive state with a delay in said change in said state to said inactive state for a selected period of time.

96. A system according to claim 95, wherein said station includes at least one workstation, each of said workstations having a display screen, said system further comprising:

means "related to/responsive to" said operation of said third means determining that said state is not currently being delayed before being changed to said inactive state, for causing said display screen to display a message indicating that said station is in said active state.

97. A system according to claim 95, further comprising:

means for signalling events relating to said active and inactive states; and

means responsive to said second means determining that said station is not in one of said unscheduled inactive states for causing said signalling means to signal the start of the next one of said scheduled inactive intervals.

98. A system according to claim 95, further comprising:

third means responsive to a determination that said station is in said unscheduled inactive state for signalling the start of the next scheduled inactive state of said station.

99. A system according to claim 95, further comprising:

fourth means responsive to said third means detrmining that said state is currently being delayed before being changed to said inactive state, for canceling said delayed change in state.

100. A system according to claim 95, wherein a first line is connected to said station for carrying emergency call notification messages to said station, further comprising:

fourth means responsive to said third means determining that said state is not currently being delayed before being changed to said inactive state, for allowing said station to receive said telephone calls.

101. A method for controlling the availability of a call ansering station to answer an emergency telephone call at a given time;

said station being adapted to be in one of an active state, a night service state or an abandoned state;

said night service state being scheduled to occur during a night service interval of time;

said abandoned state being unscheduled;

said method utilizing a computer having a first table for selectively indicating for said station said active state, said abandoned state and said night service state;

said method comprising steps for ending said night service state of said station by;

determining whether said station is in said abandoned state at the given time;

if said station is not in said abandoned state at said given time, then updating said first table to indicate that said station is in said active state.

102. A method according to claim 101, wherein said computer is provided with timer means for signalling changes to and from said inactive state of said station, said method further comprising the step of

whether or not said station is in said abandoned state at said given time, setting said timer means to signal the state of said next night service interval after said active state.

103. A method aqccording to claim 101 further comprising the steps:

determine whether at said given time said station was in condition to enter said night service state; and

if said station was in said condition, at said given time introducing a delay in the time at which said station enters said night service state.

104. A method according to claim 103, wherein said station is provided with a notification line for carrying messages for said station, said notification line having thereon a do not disturb message when said station is in said night service state, said method comprising the step of:

if said station was not in said condition, removing said do not disturb message from said notification line.

105. A method according to claim 101, wherein said station is provided with a video display terminal having a screen for displaying messages, said method further comprising the step of:

if said station is not in said abandoned state at said given time, then causing said terminal to display on said screen messages that said station is out of said night service state and is in said active state.