Devices, methods, and systems for a self-testing fire sensing device are described herein. One device includes an adjustable particle generator and a variable airflow generator configured to generate an aerosol density level, an optical scatter chamber configured to measure a rate at which the aerosol density level decreases after the aerosol density level has been generated, and a controller configured to compare the measured rate at which the aerosol density level decreases with a baseline rate, and determine whether the self-testing fire sensing device requires maintenance based on the comparison of the measured rate at which the aerosol density level decreases and the baseline rate.

A method for dynamically partitioning a security system is described. A security system identifies sensors registered with the security system. The security system then identifies a first partition attribute of a first group of sensors of the sensors. The first partition attribute indicates a primary partition of the security system. The security system then identifies a second partition attribute of a second group of sensors of the sensors. The second partition attribute indicates a secondary partition of the security system. The security system forms a dynamic partition of the security system based on a combination of the first and second partition attributes.

A method for dynamically partitioning a security system is described. A security system identifies sensors registered with the security system. The security system then identifies a first partition attribute of a first group of sensors of the sensors. The first partition attribute indicates a primary partition of the security system. The security system then identifies a second partition attribute of a second group of sensors of the sensors. The second partition attribute indicates a secondary partition of the security system. The security system forms a dynamic partition of the security system based on a combination of the first and second partition attributes.

The present invention relates to a fire pre-detection device and, particularly, to a fire pre-detection device for pre-detecting a fire on the basis of the difference between a temperature of a thermal image acquired by a thermal imaging camera and a temperature of a differential thermal image, and finally detecting the fire by using a flame detector. The fire pre-detection device according to the present invention can pre-detect a fire sign or a fire through a thermal image and finally detect the fire through the flame detector, so as to pre-detect a fire and more clearly detect the occurrence of a fire.

A gunshot detection system synchronizes timing information across gunshot sensor units and/or a control panel. The gunshot sensor units exchange timing information with each other and/or with the control panel, which is then used by the gunshot sensor units to generate the event data for detected gunshot events. In one embodiment, the gunshot sensor units are configured as master and slave nodes. The master node periodically distributes a master time reference to the slave nodes, and the slave nodes calibrate local times based on the master time reference. The slave nodes can detect whether the current master node has become non-functional (e.g. based on a time elapsed since the most recently sent master time reference) and configure a new master node based on exchanging predetermined priority information for the slave nodes.

A gunshot detection system synchronizes timing information across gunshot sensor units and/or a control panel. The gunshot sensor units exchange timing information with each other and/or with the control panel, which is then used by the gunshot sensor units to generate the event data for detected gunshot events. In one embodiment, the gunshot sensor units are configured as master and slave nodes. The master node periodically distributes a master time reference to the slave nodes, and the slave nodes calibrate local times based on the master time reference. The slave nodes can detect whether the current master node has become non-functional (e.g. based on a time elapsed since the most recently sent master time reference) and configure a new master node based on exchanging predetermined priority information for the slave nodes.

Use of multiple sensors to determine whether motion of an object is occurring in an area is described. In one aspect, an infrared (IR) sensor can be supplemented with a radar sensor to determine whether the determined motion of an object is not a false positive.

A method comprising: controlling an active reflected wave detector to measure wave reflections from an environment using a first frame rate to accrue measured wave reflection data for a classifier, after a first amount of time, determining whether a predefined criteria is satisfied, wherein satisfaction of the predefined criteria is indicative of the classifier being likely to successfully identify a fall status of a person in the environment by a second amount of time of accruing measured wave reflection data from the active reflected wave detector, the second amount of time being greater than the first amount of time; in the event that the predefined criteria is not met, the method comprising controlling the active reflected wave detector to accrue measured wave reflection data at a lower second frame rate for classifying the fall status based on measured wave reflection data accrued at the lower second rate.

A system and method of reducing the incidence of false alarms attributable to dust in smoke detection apparatus. The method includes obtaining at least two sample air flows, subjecting a first airflow to particle reduction and measuring the level of particles in the first airflow and generating a first signal indicative of the intensity. The method also includes measuring the level of particles in the second airflow and generating a second signal indicative of the intensity. The first signal is compared to a predetermined alarm level and, if the alarm level is achieved, the first and second signals are subsequently compared and an output signal is generated based on the relative difference between the first and second signals.

A system and method of reducing the incidence of false alarms attributable to dust in smoke detection apparatus. The method includes obtaining at least two sample air flows, subjecting a first airflow to particle reduction and measuring the level of particles in the first airflow and generating a first signal indicative of the intensity. The method also includes measuring the level of particles in the second airflow and generating a second signal indicative of the intensity. The first signal is compared to a predetermined alarm level and, if the alarm level is achieved, the first and second signals are subsequently compared and an output signal is generated based on the relative difference between the first and second signals.