Abstract: A method of particle detection in an aspirated particle detection system having a sampling pipe network and a particle detector. The method includes drawing sample air to the particle detector through the air sampling network; analyzing the sample air with the particle detector; entering an amplification phase, in the event that a concentration of particles in the sample air greater than a predetermined threshold is detected, to create a plurality of sample air packets in the sampling pipe, wherein each sample air packet corresponds to a sampling inlet and includes an amplified concentration of air drawn from the corresponding sampling inlet; transporting the sample air including the plurality of sample air packets through the sampling pipe to the particle detector; and determining through which sampling inlet any particles entered the particle detection system.

Abstract: A sampling point for use with an aspirating particle detection system. The sampling point includes: a body; a plurality of apertures in the body for drawing an air sample from an ambient environment; an outlet for delivering the sampled air, at a predetermined sample flow rate, from the body into a sampling pipe of the network of sampling pipes; and a means for maintaining the predetermined sample flow rate regardless of the presence or absence of ambient flow of air about the body. A particle detection system, and air sampling system are also described.

Abstract: A smoke detecting method which uses a beam of radiation such as a laser (16), to monitor a region, such as a room (12). A camera (14) is used to capture images of part of the room (12), including a path of the laser beam. Particles in the laser beam scatter light (30), and this is captured by the camera (14) for analysis. A processor (20) extracts data relating to the scattered light (30) to determine the density of particles in the beam, to determine the level of smoke in the region. The laser may have a modulated output (38) so that images captured without the laser tuned “on” can be used as a reference point and compared to images taken with the laser turned “on”, to assist in determining the level of scattered light (30) compared to ambient light. Filters (24, 26) may be used to decrease signals generated from background light.

Abstract: A smoke detecting method which uses a beam of radiation such as a laser (16), to monitor a region, such as a room (12). A camera (14) is used to capture images of part of the room (12), including a path of the laser beam. Particles in the laser beam scatter light (30), and this is captured by the camera (14) for analysis. A processor (20) extracts data relating to the scattered light (30) to determine the density of particles in the beam, to determine the level of smoke in the region. The laser may have a modulated output (38) so that images captured without the laser tuned “on” can be used as a reference point and compared to images taken with the laser turned “on”, to assist in determining the level of scattered light (30) compared to ambient light. Filters (24, 26) may be used to decrease signals generated from background light.

Abstract: A smoke detecting method which uses a beam of radiation such as a laser (16), to monitor a region, such as a room (12). A camera (14) is used to capture images of part of the room (12), including a path of the laser beam. Particles in the laser beam scatter light (30), and this is captured by the camera (14) for analysis. A processor (20) extracts data relating to the scattered light (30) to determine the density of particles in the beam, to determine the level of smoke in the region. The laser may have a modulated output (38) so that images captured without the laser tuned “on” can be used as a reference point and compared to images taken with the laser turned “on”, to assist in determining the level of scattered light (30) compared to ambient light. Filters (24, 26) may be used to decrease signals generated from background light.

Abstract: A particle detection system (100), such as an active video smoke detection system, includes at least one illumination means (102) for directing a beam (106) of radiation through at least part of the air volume being monitored (110), an image sensor (104) is positioned to capture images of at least part of a beam (106) from illumination means (102); and means to analyse (107) the captured images to detect the presence of particles within the volume. At least 29 different aspects are described for improving the sensitivity, usability, and robustness of particle detection. These include, for example, configuring illumination means (102) to create a curtain of light or a rapidly-scanned beam across the air volume (110), and configuring a reflector to steer or change direction of a beam reflected from illumination means (102).

Abstract: A smoke detecting method which uses a beam of radiation such as a laser (16), to monitor a region, such as a room (12). A camera (14) is used to capture images of part of the room (12), including a path of the laser beam. Particles in the laser beam scatter light (30), and this is captured by the camera (14) for analysis. A processor (20) extracts data relating to the scattered light (30) to determine the density of particles in the beam, to determine the level of smoke in the region. The laser may have a modulated output (38) so that images captured without the laser tuned “on” can be used as a reference point and compared to images taken with the laser turned “on”, to assist in determining the level of scattered light (30) compared to ambient light. Filters (24, 26) may be used to decrease signals generated from background light.

Abstract: The invention provides use of one or more emitted beams of radiation (16), for example, laser beam(s), in combination with an image capturing means (14), for example, one or more video cameras and/or optical elements to detect particles (30), for example, smoke particles, located in an open space (12).

Abstract: A method of detecting one or more blocked sampling holes in a pipe of an aspirated smoke detector system. The method includes ascertaining the base flow of fluid through a particle detector using a flow sensor; monitoring subsequent flow through the particle detector; comparing the subsequent flow with the base flow; and indicating a fault if the difference between the base flow and the subsequent flow exceeds a predetermined threshold.

Abstract: A particle detection system (100), such as an active video smoke detection system, includes at least one illumination means (102) for directing a beam (106) of radiation through at least part of the air volume being monitored (110), an image sensor (104) is positioned to capture images of at least part of a beam (106) from illumination means (102); and means to analyze (107) the captured images to detect the presence of particles within the volume. At least 29 different aspects are described for improving the sensitivity, usability, and robustness of particle detection. These include, for example, configuring illumination means (102) to create a curtain of light or a rapidly-scanned beam across the air volume (110), and configuring a reflector to steer or change direction of a beam reflected from illumination means (102).

Abstract: The invention provides use of one or more emitted beams of radiation (16), for example, laser beam(s), in combination with an image capturing means (14), for example, one or more video cameras and/or optical elements to detect particles (30), for example, smoke particles, located in an open space (12).

Abstract: A smoke detecting method which uses a beam of radiation such as a laser (16), to monitor a region, such as a room (12). A camera (14) is used to capture images of part of the room (12), including a path of the laser beam. Particles in the laser beam scatter light (30), and this is captured by the camera (14) for analysis. A processor (20) extracts data relating to the scattered light (30) to determine the density of particles in the beam, to determine the level of smoke in the region. The laser may have a modulated output (38) so that images captured without the laser tuned “on” can be used as a reference point and compared to images taken with the laser turned “on”, to assist in determining the level of scattered light (30) compared to ambient light. Filters (24, 26) may be used to decrease signals generated from background light.

Abstract: 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.

Abstract: There is described a duct detector and components for duct detectors. In one form the duct detector includes: a port unit and detector unit. The port unit is mountable to a duct in use so as to position one or more ports in the duct. The detector unit includes a detection region. The port unit and detector unit are reconfigurable between a close coupled configuration and a separated configuration in which the units are mountable with a variable separation between them and coupled by one or more elongate conduits to provide fluid communication between the units.

Abstract: There is described a filter arrangement for a particle detector for detecting particles in an environment. The particle detector can include one or more sensors for analyzing fluid in a detection region to produce sensor output. The filter arrangement includes structure defining flow paths, for conveying fluid from the environment towards the detection region, including a first flow path, which includes a filter, and a second flow path bypassing the filter. There is also provided a mechanism for controlling relative flow rates of fluid through the first flow path and the second flow path and a controller configured to receive the sensor output corresponding to at least two relative flow rates and apply logic thereto to generate an output indicative of a condition of the filter.

Abstract: A filter arrangement for removing impurities from a fluid is disclosed, the filter arrangement (10) includes a plurality of screen portions (18, 20) through which the fluid passes. The screen portions include a first screen portion (18) and a second screen portion (20) separated by a predetermined distance. The predetermined distance can be determined on the basis of a threshold particle length. In one form the filter arrangement (10) is mounted in a housing (16) which is configured to receive two filter elements (18, 20) arranged in a nested configuration. A particle detector using the filter is described.

Abstract: An apparatus and methods for detecting the presence of gases is described. The gas detection apparatus includes, a housing adapted to be in fluid communication with a duct of a particle detection system, and at least one gas detector sensitive to a target species arranged in fluid communication with the housing to detect the presence of the target species in at least part of the air sample flowing in a duct. In one form the gas detection apparatus forms part of a system for detecting a condition in an environment that includes, a particle detector; a duct system in fluid communication with the environment and the particle detector and an aspirator to draw an air sample flow from the environment to the particle detector.

Abstract: In one form the present invention provides an apparatus in an airflow path before a particle detector, wherein the apparatus removes a substantially constant proportion of all sizes of airborne particles from the airflow over time. In an example the apparatus includes a flow splitting arrangement configured to divide a fluid flow into a plurality of sub-flows, the splitting arrangement 10 including means for defining a plurality of substantially identically dimensioned flow apertures configured to direct a portion of the fluid into a respective sub-flow.

Abstract: A particle detection system including; at least one light source adapted to illuminate a volume being monitored at least two wavelengths; a receiver) having a field of view and being adapted to receive light from at least one light source after said light has traversed the volume being monitored and being adapted to generate signals indicative of the intensity of light received at regions within the field of view of the receiver; a processor associated with the receiver adapted to process the signals generated by the receiver to correlate light received at least two wavelengths in corresponding regions within the field of view of the receiver and generate an output indicative of the relative level of light received at the two wavelengths.