A detector (10; 110) is provided for mounting to a container (2) defining an internal space (6) in order to determine occupancy of the container. The detector includes a housing (12; 112), a mounting arrangement for mounting the housing to a container, a sensor arrangement comprising a first sensor (30; 130) disposed within the housing, the first sensor configured to determine a concentration of carbon dioxide within an internal space (6) of a container (2); and a control system (40; 140) configured to receive input values from the first sensor and to provide an output when the concentration of carbon dioxide exceeds a predetermined value. The housing is substantially sealed for preventing the ingress of debris into the housing, and the housing is configured such that air is able to flow into the housing and over the first sensor.

An apparatus, method, and system for detecting an object in an environment. The apparatus comprises: a processor configured to: control an active reflected wave detector to measure wave reflections from the environment to accrue measured wave reflection data; process the measured wave reflection data to detect an object in said environment; in response to detection of said object, determine whether a first predetermined condition in respect of the object is met; and if the first predetermined condition is met, control an output device to output a deterrent.

Disclosed is an electronic device comprising: a communication circuit, at least one sensor for sensing an open-or-closed state of a door and a person near the door, a processor electrically connected to the communication circuit and the at least one sensor, and a memory electrically connected to the processor.

A notification system for location-based fingerprint detection includes a wireless device scanner, at least one sensor, and a remote server. The sensor is configured to sense parameters indicative of an event. The system further includes a processor, and a memory having stored thereon instructions which, when executed by the processor, cause the notification system to: detect an occurrence of the event based on the sensed parameters; receive, by the wireless device scanner, a wireless signal of a user device; determine a unique identifier of the user device based on the wireless signal, wherein the wireless signal includes a wireless signal noise level for the user device; and transmit the determined unique identifier to the remote server.

A monitoring system that is configured to monitor a property is disclosed. The monitoring system includes a passive infrared (PIR) sensor configured to generate reference PIR data that represents motion within an area of the property; an auxiliary sensor configured to generate auxiliary sensor data that represents an attribute of the area of the property; and a motion sensor device. The motion sensor device is configured to: obtain the reference PIR data; determine that a first set of motion detection criteria is satisfied by the reference PIR data; in response to determining that the first set of motion detection criteria is satisfied by the reference PIR data, obtain the auxiliary sensor data; obtain a second set of motion detection criteria based on the reference PIR data and the auxiliary sensor data; and determine whether the second set of motion detection criteria is satisfied by additional PIR data.

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.

One variation of a method for detecting a fire includes: during a first time period: detecting an increase in ambient light intensity and detecting an increase in ambient humidity; responsive to the increase in ambient light intensity and the increase in ambient humidity, detecting a fire event; during a second time period: correlating a decrease in ambient light intensity with an increase in visual obscuration; detecting an increase in ambient air temperature; in response to a magnitude of the increase in visual obscuration remaining below a high obscuration threshold and a magnitude of the increase in ambient temperature remaining below a high temperature threshold, classifying the fire as an incipient fire; and, in response to the magnitude of the increase in visual obscuration exceeding the high obscuration threshold and the magnitude of the increase in ambient temperature exceeding the high temperature threshold, classifying the fire as a developed fire.

A photoelectric smoke detector (14) connected to a signal line (12-1) drawn into a warning area from a receiver (10) transmits a fire signal including identification information of smoke caused in detection zones Z1 and Z2. In the detection zones, a sensor (18) for sensing a change of physical phenomenon other than smoke involved in fire is provided, and the sensor (18) is connected to the signal line (12-1) via a relay device (16). The sensor (18) is at least one of a CO.sub.2 sensor, a CO sensor, a fire sensor, and a heat sensor. A fire alarm control unit (48) of the receiver (10) causes an alarm to be given, when determining the identification information of the smoke by the photoelectric smoke detector (14) and a sensing value by at least one of the CO.sub.2 sensor, the CO sensor, the fire sensor, and the heat sensor.

One variation of a method for detecting a fire includes: during a first time period: detecting an increase in ambient light intensity and detecting an increase in ambient humidity; responsive to the increase in ambient light intensity and the increase in ambient humidity, detecting a fire event; during a second time period: correlating a decrease in ambient light intensity with an increase in visual obscuration; detecting an increase in ambient air temperature; in response to a magnitude of the increase in visual obscuration remaining below a high obscuration threshold and a magnitude of the increase in ambient temperature remaining below a high temperature threshold, classifying the fire as an incipient fire; and, in response to the magnitude of the increase in visual obscuration exceeding the high obscuration threshold and the magnitude of the increase in ambient temperature exceeding the high temperature threshold, classifying the fire as a developed fire.

A monitoring system that is configured to monitor a property is disclosed. The monitoring system includes a passive infrared (PIR) sensor configured to generate reference PIR data that represents motion within an area of the property; an auxiliary sensor configured to generate auxiliary sensor data that represents an attribute of the area of the property; and a motion sensor device. The motion sensor device is configured to: obtain the reference PIR data; determine that a first set of motion detection criteria is satisfied by the reference PIR data; in response to determining that the first set of motion detection criteria is satisfied by the reference PIR data, obtain the auxiliary sensor data; obtain a second set of motion detection criteria based on the reference PIR data and the auxiliary sensor data; and determine whether the second set of motion detection criteria is satisfied by additional PIR data.