Abstract: An electrochemical cell for detecting a gas from the surrounding environment. The cell comprises an electrolyte and a sensing electrode which is in fluid communication with the electrolyte and the gas to be detected, when present. The cell further comprises a counter electrode in fluid communication with said electrolyte, and also a source of reactant gas provided in a cavity adjacent to the counter electrode, wherein reaction of the gas to be detected at the sensing electrode results in reaction of the reactant gas at the counter electrode and wherein the cavity is formed of or comprises a membrane. The cell may also have a wick extending between the sensing electrode and the counter electrode in an axial direction and a reservoir surrounding the wick.

Abstract: A remote alarm monitoring system (10) for recording and processing alarm event data. The alarm system (10) comprises one or more alarm devices (12) in connection with an interface (14), wherein the interface (14) is configured to receive alarm event data; a server (18) in communication with the interface (14), wherein the server (18) is configured to receive and process alarm event data from the interface (14); and one or more networked client devices (22) in communication with the server (18), wherein the server (18) is configured to transmit a message to the networked client device (22), said message based upon the processed alarm event data.

Abstract: A heat sensing module for a heat alarm apparatus comprises a base section having a concave surface, a cage, a heat sensor, and a control circuit configured to detect a temperature rise at the heat sensor and output an alarm signal in response thereto. A sensing part of the heat sensor is located in a space formed between the concave surface of the base section and the cage. The concave surface assists with reflecting, radiating and absorbing heat to increase the speed at which the heat sensor registers a change in temperature.

Abstract: An alarm apparatus, for detecting radiation and/or pollutants including smoke and carbon monoxide, comprises an alarm circuit including a detector for radiation and/or pollutants and an audible alarm emitting device. A power supply circuit, connectable to an external AC power supply, supplies power to the alarm circuit. A controller operates the power supply circuit in a first mode of operation in which it supplies current to the alarm circuit at a first power level less than that required to energize the audible alarm emitting device and, in response to the detection of radiation and/or pollutants, operates the power supply in a second mode of operation in which it supplies current to the alarm circuit at a second power level sufficient to energize the audible alarm emitting device.

Abstract: A heat alarm apparatus includes a housing defining a body, a sensor mounting panel located on the body and a heat sensor extending from the sensor mounting panel. A control circuit is configured to detect a temperature rise at the heat sensor and output an alarm signal in response thereto. At least the surface of the sensor mounting panel from which the heat sensor extends is a dark color.

Abstract: An optical smoke detector (110) is provided that comprises a housing (112) having a base (114) for attaching the detector to a surface and a cover (116) having a side wall (124) and a bottom wall (126) defining the interior of said cover. An optical sensor (131) is provided for generating a signal representative of the detected light and a control circuit (130) is provided for controlling operation of the detector. The control circuit (130) includes a plurality of temperature sensors (D1, D2) for sensing a rise in ambient temperature and generating a signal representative thereof. The temperature sensors (D1, D2) are located above an internal surface of said bottom wall (126) within the housing and are substantially equally spaced. The control circuit (30) is operable to compare said representative signal with a reference signal and generate an alarm signal in dependence thereon.

Abstract: An alarm for detecting smoke comprises a housing (1) having vents (9) for allowing ingress of smoke into the housing. A sensor chamber (22,26) is disposed within the housing and has vents (24a,24b) for allowing ingress of smoke into the sensor chamber and comprises two parts. A diode emitter and diode sensor (25) is mounted within the sensor chamber for sensing light reflected off smoke. An alarm circuit (32), including detection means for detecting smoke sensed by the sensor diode (25), is supported on a printed circuit board (PCB) (29). The PCB is sandwiched between two halves (22 and 26) of the sensor chamber such that an edge (30) thereof extends part-way into said sensor chamber. The sensor is mounted on, near or adjacent to the edge.

Abstract: An optical smoke detector (10) is provided that comprises a light source (154), a light receiver (172), and a control circuit (130) for controlling operation of the detector. The control circuit (130) is configured to apply an unregulated voltage to the light source to cause it to emit light, to monitor the current through said light source (154) so as to monitor the light emitted by said light source (154); and to monitor the current generated by light received by said light receiver (172) so as to monitor the light received by said light receiver (172). The control circuit (130) generates a ratio signal representative of the ratio of the monitored currents; and compares the ratio signal with a reference value and generate a smoke detection signal in dependence thereon.

Abstract: An alarm for detecting radiation and/or air pollutants such as smoke, carbon monoxide or the like has a control circuit (11) including a microcontroller (12) configured to monitor preselected alarm parameters, and memory means (30, 36, 40) for storing data representing said parameters. The microcontroller (12) has an input/output means (3) connectible both to a preselected voltage level for switching said control circuit between an operational mode and a shutdown mode and to an external processing means for enabling downloading and display of said data.

Abstract: An alarm for detecting radiation and/or pollutants such as smoke, carbon monoxide or the like, the alarm comprises: an alarm circuit (12) including detection means (14) for detecting the radiation and/or pollutants, and an audible alarm (16); a power supply circuit (24) connectable to an external AC power supply for supplying standby power to the alarm circuit (12); and a battery (20) for supplying power to the audible alarm (16) when the alarm is energized. The power supply circuit (20) is configured to supply current to the alarm circuit (12) at a level less than that required to energize the audible alarm (16).

Abstract: An optical smoke detector (110) is provided that comprises a housing (112) having a base (114) for attaching the detector to a surface and a cover (116) having a side wall (124) and a bottom wall (126) defining the interior of said cover. An optical sensor (131) is provided for generating a signal representative of the detected light and a control circuit (130) is provided for controlling operation of the detector. The control circuit (130) includes a plurality of temperature sensors (D1, D2) for sensing a rise in ambient temperature and generating a signal representative thereof. The temperature sensors (D1, D2) are located above an internal surface of said bottom wall (126) within the housing and are substantially equally spaced. The control circuit (30) is operable to compare said representative signal with a reference signal and generate an alarm signal in dependence thereon.

Abstract: An alarm for detecting smoke comprises a housing (1) having vents (9) for allowing ingress of smoke into the housing. A sensor chamber (22,26) is disposed within the housing and has vents (24a,24b) for allowing ingress of smoke into the sensor chamber and comprises two parts. A diode emitter and diode sensor (25) is mounted within the sensor chamber for sensing light reflected off smoke. An alarm circuit (32), including detection means for detecting smoke sensed by the sensor diode (25), is supported on a printed circuit board (PCB) (29). The PCB is sandwiched between two halves (22 and 26) of the sensor chamber such that an edge (30) thereof extends part-way into said sensor chamber. The sensor is mounted on, near or adjacent to the edge.