with respect to fig1 there is illustrated one embodiment of a fire suppression system 100 comprising an electronic system having electric circuits for detecting , identifying , and recording the presence of persons 112 within a monitored area 113 . fire suppression system 100 includes a fire detector 105 , electronic id readers or detectors 103 , 104 , rfid detector 110 , an audible and visible alarm 119 , fire suppressant containers 108 , 109 , fire suppressant tank outlets 116 , 117 , all electrically connected to fire control processing system 106 over communication channel 107 . a person 111 not within monitored area 113 enters monitored area 113 through entry / exit points 101 , 102 . similarly , a person 112 within monitored area 113 exits monitored area 113 through entry / exit points 101 , 102 . fire suppressant tanks 114 , 115 for flooding monitored area 113 are connected to fire suppressant tank outlets 116 , 117 , respectively , via pipes 118 . electronic id readers or detectors 103 , 104 may be deployed at each entry / exit point 101 , 102 for detecting entry and exit by persons into and out of monitored area 113 . such devices may comprise employee badge readers , which can be card - based magnetic strip reading devices or bar code reading devices ; text input devices such as keypads or other input devices for inputting id numbers or names ; radio frequency identification ( rfid ) reading devices which comprise circuitry for detecting an rfid source worn or carried by an employee , worker or other person ; a facial imaging and recognition device which includes a digital camera for capturing an image of a person &# 39 ; s face and facial recognition programming for identifying the person based on the captured facial image ; a retinal imaging and recognition device which captures an image of a portion of a person &# 39 ; s eye for identifying the person based on retinal patterns ; a voice recognition device for receiving a voice sample from a person in order to identify the person based on voice characteristics ; a fingerprint reader ; a hand print reader ; or any combination thereof . the id readers or detectors 103 , 104 are placed at each entry / exit point 101 , 102 and contain electric circuits for detecting and reading id information from each person entering and exiting monitored area 113 . the id information so detected is electronically stored in electronic memory of fire control processing system 106 or in memory that is accessible by fire control processing system 106 . instead of , or in combination with , the readers and detectors just described , an rfid detection system may be deployed within monitored area 113 to track personnel that are present within monitored area 113 by detecting rfid devices worn or carried by personnel within monitored area 113 . persons entering within range of rfid detector 110 are detected , identified , and recorded as being present in monitored area 113 . conversely , persons that depart monitored area 113 are detected , identified , and recorded as being no longer present in range of rfid detector 110 in monitored area 113 . such detection systems , as described herein , can be used to store the detected identification data and used in conjunction with , for example , an employee database that may be part of a standard security system employed by a company for controlling entry to monitored areas 113 of work sites by authorized personnel . the fire control processing system 106 may be configured to have access to such a security system database . each electronic id reader or detector 103 , 104 , or the personnel id data generated thereby , is accessible by fire control processing system 106 for determining , at any time , the presence of persons within monitored area 113 . fire control processing system 106 can be configured to be connected to , or part of , such a standard security system for tracking personnel that enter and exit monitored area 113 . databases utilized for tracking such personnel can be electrically connected to fire control processing system 106 such that fire control processing system 106 can freely access such data to determine whether there are persons who have entered but not exited the monitored area 113 via the entry / exit points 101 , 102 . in the embodiment shown in fig1 , the fire control processing system 106 directly manages and is directly connected to the electronic id readers and detectors 103 , 104 using communication channel 107 . in the embodiment shown in fig1 , fire control processing system 106 comprises a processor and memory for managing personnel id data and for storing and executing programs according to the algorithms described herein . the fire control processing system 106 can be located proximate to or remote from monitored area 113 . communication channel 107 represents either a wired communication channel 107 or a wireless communication channel . wired communication channel 107 can be implemented as a networked communication channel , such as an ethernet or usb communication channel , or a privately designed communication channel . similarly , the communication channel implemented as a wireless communication channel can be implemented as a wifi , cellular , or a privately designed wireless communication channel . fire control processing system 106 may comprise a microcontroller , memory , and electric circuits for executing a stored computer program triggered by reception of the fire condition signal from fire detector 105 . fire control processing system 106 may be embodied in an application executed on a general purpose processing system such as a pc or laptop , a site wide server , or a network - based system remotely located from monitored area 113 and communicating , over communication channel 107 implemented as an internet connection , with fire detector 105 or other detection devices proximate to monitored area 113 . in one embodiment , communication channel 107 may comprise , in various combinations , an internet connection , a cellular network connection , a wired network connection and a wifi connection interoperating to maintain communication between detection devices proximate to monitored area 113 and fire control processing system 106 connected remotely to such devices . in one embodiment , electronic id readers and detectors 103 , 104 are not configured to identify each person entering and exiting monitored area 113 . rather , the electronic id readers and detectors 103 , 104 track persons who enter and exit monitored area 113 without identifying such persons and merely keep track of a total count of persons entering and exiting monitored area 113 . such devices can comprise one or more of the readers and detectors described above and can further include other means for tracking entry and exit of persons from monitored area 113 , such as turnstiles , infrared detectors , and light beam detectors , for example . an rfid detection system using rfid detector 110 can anonymously detect persons carrying or wearing generic rfid tags . rfid detector 110 can be replaced or used together with a motion detector or infrared detector for determining that one or more persons are present or not present within monitored area 113 . any such detection devices communicate detection data to fire control processing system 106 as described above to indicate whether detection data indicates the presence of one or more persons within monitored area 113 . detected motion by a motion detector , or a total entry count higher than an exit count at entry / exit points 101 , 102 are further examples of data indicating the presence of persons in monitored area 113 . the fire suppressant container 109 is designated to store a human - safe fire suppressant , and container 108 is designated to store a carbon dioxide - based fire suppressant , wherein each container is connected to fire control processing system 106 using communication channel 107 . each of fire suppressant containers 108 , 109 comprise an electrically actuable valve for releasing its contents under pressure upon receiving an electric signal from fire control processing system 106 over communication channel 107 to open its valve . similarly , the valves in fire suppressant containers 108 , 109 close in response to receiving a second electric signal from fire control processing system 106 over communication channel 107 for terminating release of fire suppressant . the fire suppression system 100 is automated and is programmed to constantly monitor an area 113 such as a region on a factory floor , or other commercial or private premises wherein various personnel may enter and exit via one or more entry / exit points 101 , 102 . the premises may be occupied by at least one person intermittently , during scheduled times , or at all times . a programmed operation of fire suppression system 100 is triggered upon receiving a signal at fire control processing system 106 from fire detector 105 that a fire condition has been detected , as described below . in one embodiment , one or more fire detectors such as fire detector 105 is powered via battery power or permanent site power supply , and constantly monitors area 113 . upon detecting a fire condition , fire detector 105 issues an electric signal to fire control processing system 106 over communication channel 107 . fire detector 105 may comprise any conventional fire detection means such as a smoke detector or a heat detector . in one embodiment , a smoke detector may comprise a photodetector that monitors clarity of the air within smoke detector and is triggered when fire generated smoke particles affect transmissivity of the air within the detector above or below a preset threshold . in another embodiment , a smoke detector may comprise a ionization detector that monitors the air within the smoke detector and is triggered when fire generated smoke particles affect conductivity of ionized air within the smoke detector above a certain preset threshold . the fire detector 105 may also comprise a combination of the above types of smoke detectors . in another embodiment , fire detector 105 may be a heat detector , such as a temperature reading electronic heat detector , or an eutectic alloy ( melting switch ) heat detector , or a rate - of - rise heat detector , or a combination of the above . in one embodiment , the fire detection mechanism may be powered by connecting it to a permanent building power supply ( mains ), a battery , or capacitor - based power supply , or in any combination thereof , and using any combination thereof as a backup power supply . the preceding examples of fire detection mechanisms are not to be interpreted in a limiting sense , and are described herein as exemplary detection mechanisms useable with embodiments of the present invention . any other type of fire detection device used in fire suppression system 100 is contemplated as an embodiment of the present invention . the human - safe fire suppressant in fire suppressant container 109 may include a dry chemical powder ( dcp ) fire extinguishing agent , or another fire suppressant that is safe for humans , to be used when one or more persons are detected inside monitored area 113 during a fire condition . fire suppressant container 109 using a dcp fire suppressant is available in portable cylinders pressurized with nitrogen . similarly , fire suppressant container 108 using a carbon dioxide - based fire suppressant is available in portable pressurized cylinders . in one embodiment , large fire suppressant tanks 114 , 115 are connected with piping system 118 to fire suppressant tank outlets 116 , 117 respectively . the outlets are capable of selectively flooding monitored area 113 under control of an electric signal from fire control processing system 106 over communication channel 107 to either or both of fire suppressant tank outlets 116 , 117 . in this embodiment , fire suppressant tank 114 comprises a carbon dioxide - based fire suppressant in sufficient quantities for flooding monitored area 113 , while fire suppressant tank 115 comprises a fire suppressant safe for humans in sufficient quantities for flooding monitored area 113 , such as the dcp described above . both fire suppressant tank outlets 116 , 117 comprise valves selectively electrically actuable , individually or together , under control from an electric signal received from fire control processing system 106 over communication channel 107 to open and release fire suppressant from the fire suppressant tanks 114 , 115 , respectively , through a corresponding pipe 118 and through fire suppressant tank outlets 116 , 117 for flooding monitored area 113 . similarly , the valves in fire suppressant tank outlets 116 , 117 are selectively electrically actuable to close , for terminating the release of fire suppressant into monitored area 113 upon receiving a second signal from fire control processing system 106 . the dcp in fire suppressant container 109 and in fire suppressant tank 115 may comprise monoammonium phosphate . monoammonium phosphate is a well - known fire suppressant and is non - toxic to human beings . in the event that carbon dioxide has been released , or carbon dioxide is otherwise present , and a person is in , or enters , the monitored area 113 during a fire condition state , the dcp from fire suppressant container 109 or from fire suppressant tank 115 may be released into monitored area 113 as described below . with reference to fig2 , there is illustrated a fire control processing system algorithm 200 performed by fire control processing system 106 according to a program stored in a memory of fire control processing system 106 . as described above , fire detector 105 constantly monitors area 113 for a fire condition . when fire detector 105 detects a fire condition , it transmits an electric signal over communication channel 107 to fire control processing system 106 which interprets the signal as a fire condition detected signal at step 201 . at step 202 , fire control processing system 106 triggers an audible and visible alarm 119 in monitored area 113 by sending an electrical signal to alarm 119 over communication channel 107 . at step 203 , fire control processing system 106 determines if one or more people are present in monitored area 113 as described above . for example , fire control processing system can access an id information database to determine that people who have entered monitored area 113 have not yet exited , that a total entry count is less than a total exit count , that rfid detector 110 is currently detecting rfid tags in monitored area 113 , or that a motion detector is currently detecting motion in monitored area 113 . if fire control processing system 106 determines that one or more people are present in monitored area 113 , then at step 204 fire control processing system 106 sends an electric signal over communication channel 107 to human - safe fire suppressant container 109 , or to human - safe fire suppressant tank outlet 117 , or both , which causes corresponding valves to open and release human - safe fire suppressant from container 109 into monitored area 113 , and / or from tank 115 through fire suppressant tank outlet 117 for flooding monitored area 113 . a programmed delay occurs at step 205 for a preselected duration to allow time for people present in monitored area 113 to evacuate . at step 206 , fire control processing system 106 checks to determines if people are present in monitored area 113 . if fire control processing system 106 determines that people are still present in monitored area 113 then the human - safe fire suppressant continues to be released at step 204 until it is depleted , manually shut off , or the fire control processing system no longer detects a fire condition . if fire control processing system 106 determines at step 206 that people are no longer present in monitored area 113 , then the fire control processing system 106 sends an electric signal over communication channel 107 to carbon dioxide - based fire suppressant container 108 , or to carbon dioxide - based fire suppressant tank outlet 116 , or both , which causes the corresponding valves to open and release carbon dioxide - based fire suppressant from container 108 into monitored area 113 , and / or from fire suppressant tank 114 for flooding monitored area 113 through fire suppressant tank outlet 116 . the release of carbon dioxide - based fire suppressant at step 207 , following decision step 206 , may include fire control processing system 106 sending a second electric signal over communication channel 107 to fire suppressant container 109 , or to fire suppressant tank outlet 117 , or both , to close their valves and terminate release of the human - safe fire suppressant , or the human - safe fire suppressant can continue to be released together with the carbon dioxide - based fire suppressant . after step 207 , at step 206 , fire control processing system 106 determines if people are present in monitored area 113 . if fire control processing system 106 determines that people are still no longer present in monitored area 113 then the carbon dioxide - based fire suppressant continues to be released at step 207 until it is depleted , manually shut off , the fire control processing system no longer detects a fire condition , or until fire control processing system 106 detects that people are present at step 206 . if fire control processing system 106 determines at step 206 that people are present in monitored area 113 after a release of carbon dioxide - based fire suppressant at step 207 , then , at step 208 the fire control processing system 106 sends a second electric signal over communication channel 107 to carbon dioxide - based fire suppressant container 108 , or to carbon dioxide - based fire suppressant tank outlet 116 , or both , which causes the corresponding valves to close and terminate release of the carbon dioxide - based fire suppressant from container 108 and / or from fire suppressant tank 114 into monitored area 113 . at step 204 , if the human - safe fire suppressant container 109 and / or fire suppressant tank outlet 117 was not closed , the human - safe fire suppressant continues to be released until it is depleted , manually shut off , or the fire control processing system no longer detects a fire condition . if the human - safe fire suppressant container 109 and fire suppressant tank outlet 117 were closed , then fire control processing system 106 again sends an electric signal over communication channel 107 to human - safe fire suppressant container 109 , or to human - safe fire suppressant tank outlet 117 , or both , which causes corresponding valves to open and again release human - safe fire suppressant from container 109 into monitored area 113 , and / or from tank 115 through fire suppressant tank outlet 117 for flooding monitored area 113 . the fire control processing system algorithm 200 then continues through to step 206 as described above . returning back to step 203 , if , after receiving a fire condition detected signal at step 201 and triggering the alarm at step 202 , fire control processing system 106 determines that no people are present in monitored area 113 , then at step 207 the fire control processing system 106 sends an electric signal over communication channel 107 to carbon dioxide - based fire suppressant container 108 , or to carbon dioxide - based fire suppressant tank outlet 116 , or both , which causes the corresponding valves to open and release carbon dioxide - based fire suppressant from container 108 into monitored area 113 , and / or from fire suppressant tank 114 for flooding monitored area 113 through fire suppressant tank outlet 116 . in one embodiment , the release of carbon dioxide - based fire suppressant at step 207 may include fire control processing system 106 also sending an electric signal over communication channel 107 to fire suppressant container 109 , or to fire suppressant tank outlet 117 , or both , to simultaneously release the human - safe fire suppressant into monitored area 113 together with the carbon dioxide - based fire suppressant . after step 207 , at step 206 , fire control processing system 106 determines if people are present in monitored area 113 , and the algorithm continues as described above . in view of the foregoing , embodiments of the invention provide an automatic fire suppressant release system designed to protect people in the vicinity of the fire from hazardous fire suppressants . a technical effect is to automate the fire suppressant system without requiring manual mechanical shut off of fire suppressants that are hazardous to people . as will be appreciated by one skilled in the art , aspects of the present invention may be embodied as a system , method , or computer program product . accordingly , aspects of the present invention may take the form of an entirely hardware embodiment , an entirely software embodiment ( including firmware , resident software , micro - code , etc . ), or an embodiment combining software and hardware aspects that may all generally be referred to herein as a “ service ,” “ circuit ,” “ circuitry ,” “ module ,” and / or “ system .” furthermore , aspects of the present invention may take the form of a computer program product embodied in one or more computer readable medium ( s ) having computer readable program code embodied thereon . any combination of one or more computer readable medium ( s ) may be utilized . the computer readable medium may be a computer readable signal medium or a computer readable storage medium . a computer readable storage medium may be , for example , but not limited to , an electronic , magnetic , optical , electromagnetic , infrared , or semiconductor system , apparatus , or device , or any suitable combination of the foregoing . more specific examples ( a non - exhaustive list ) of the computer readable storage medium would include the following : an electrical connection having one or more wires , a portable computer diskette , a hard disk , a random access memory ( ram ), a read - only memory ( rom ), an erasable programmable read - only memory ( eprom or flash memory ), an optical fiber , a portable compact disc read - only memory ( cd - rom ), an optical storage device , a magnetic storage device , or any suitable combination of the foregoing . in the context of this document , a computer readable storage medium may be any tangible medium that can contain , or store a program for use by or in connection with an instruction execution system , apparatus , or device . program code and / or executable instructions embodied on a computer readable medium may be transmitted using any appropriate medium , including but not limited to wireless , wireline , optical fiber cable , rf , etc ., or any suitable combination of the foregoing . computer program code for carrying out operations for aspects of the present invention may be written in any combination of one or more programming languages , including an object oriented programming language such as java , smalltalk , c ++ or the like and conventional procedural programming languages , such as the “ c ” programming language or similar programming languages . the program code may execute entirely on the user &# 39 ; s computer ( device ), partly on the user &# 39 ; s computer , as a stand - alone software package , partly on the user &# 39 ; s computer and partly on a remote computer or entirely on the remote computer or server . in the latter scenario , the remote computer may be connected to the user &# 39 ; s computer through any type of network , including a local area network ( lan ) or a wide area network ( wan ), or the connection may be made to an external computer ( for example , through the internet using an internet service provider ). aspects of the present invention are described herein with reference to flowchart illustrations and / or block diagrams of methods , apparatus ( systems ) and computer program products according to embodiments of the invention . it will be understood that each block of the flowchart illustrations and / or block diagrams , and combinations of blocks in the flowchart illustrations and / or block diagrams , can be implemented by computer program instructions . these computer program instructions may be provided to a processor of a general purpose computer , special purpose computer , or other programmable data processing apparatus to produce a machine , such that the instructions , which execute via the processor of the computer or other programmable data processing apparatus , create means for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks . these computer program instructions may also be stored in a computer readable medium that can direct a computer , other programmable data processing apparatus , or other devices to function in a particular manner , such that the instructions stored in the computer readable medium produce an article of manufacture including instructions which implement the function / act specified in the flowchart and / or block diagram block or blocks . the computer program instructions may also be loaded onto a computer , other programmable data processing apparatus , or other devices to cause a series of operational steps to be performed on the computer , other programmable apparatus or other devices to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks . this written description uses examples to disclose the invention , including the best mode , and also to enable any person skilled in the art to practice the invention , including making and using any devices or systems and performing any incorporated methods . the patentable scope of the invention is defined by the claims , and may include other examples that occur to those skilled in the art . such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims , or if they include equivalent structural elements with insubstantial differences from the literal language of the claims .
a system and method for fire suppression proactively identifies persons present , during a fire , in a fire suppressant release area . the persons are identified using an electronic monitoring system . an fire suppression system using a suppressant that is effective but unsafe for humans is put into service only if no person is detected . in situations where a person is present , an alternate fire suppressant is released that is safe for humans .