Abstract: A particle detector, e.g. a smoke detector is described. In one form the detector includes a detection chamber and radiation source emitting a single beam of radiation. The detector also includes a radiation receiving system and an imaging system arranged to receive radiation from a common region of interest. Methods and systems for analysing the output of a particle detector are also disclosed.

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 particle detector, e.g. a smoke detector is described. In one form the detector includes a detection chamber and radiation source emitting a single beam of radiation. The detector also includes a radiation receiving system and an imaging system arranged to receive radiation from a common region of interest. Methods and systems for analyzing the output of a particle detector are also disclosed.

Abstract: A particle detection system including; at least one light source adapted to illuminate a volume being monitored at 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 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.

Abstract: There is described a duct detector (1) and components (2, 3, 6) for duct detectors. In one form the duct detector (1) includes: a port unit (3) and detector unit (2). The port unit (3) is mountable to a duct in use so as to position one or more ports in the duct. The detector unit (2) includes a detection region. The port unit (3) and detector unit (2) are reconfigurable between a close coupled configuration and a separated configuration in which the units (2,3) are mountable with a variable separation between them and coupled by one or more elongate conduits (12A, 12B) to provide fluid communication between the units (2,3).

Abstract: An air sampling system for a low-temperature space is disclosed. The air sampling system includes an air sampling pipe for passing sampling air to an air sampling device, and a sampling conduit extending from the low-temperature space to outside the low-temperature space. The sampling conduit is connected to the sampling pipe. The sampling conduit is selectively accessible from outside the low-temperature space for removal of ice build-up within the sampling conduit. Also disclosed is a kit for an air sampling system. Also disclosed is a method, computing system, air-sampling device and air monitoring system that evaluates an air sampling network.

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 beam detector including a light source, a receiver, and a target, acting in cooperation to detect particles in a monitored area. The target reflects incident light, resulting in reflected light being returned to receiver. The receiver is capable of recording and reporting light intensity at a plurality of points across its field of view. In the preferred form the detector emits a first light beam in a first wavelength band; a second light beam in a second wavelength band; and a third light beam in a third wavelength band, wherein the first and second wavelengths bands are substantially equal and are different to the third wavelength band.

Abstract: A particle separation system for separating particles in an airflow upstream of a detection chamber in an aspirating smoke detector is disclosed. The particle separation system includes an airflow path for directing the airflow from an inlet to an outlet. The airflow path includes a first airflow path section in a first direction and a second airflow path section in a second direction, the first and second directions being different relative to each other. The airflow path also includes at least one electrically charged surface such that the airflow undergoes electrostatic precipitation as it traverses the airflow path. A method of separating particles in an airflow upstream of a detection chamber in an aspirating smoke detector is also disclosed.

Abstract: A particle detection system including a particle detector in fluid communication with at least two sample inlets for receiving a sample flow from a monitored region. The particle detector includes detection means for detecting the level of particles within the sample flow and outputting a first signal indicative of the level of particles within the sample flow. A flow sensor is located downstream of the sample inlets for measuring the flow rate of the sample flow and outputting a second signal indicative of the flow rate of the sample flow. At least a first sample inlet is normally open to the monitored region for receiving at least part of the sample flow. At least a second sample inlet is normally closed to the monitored region but is openable to the monitored region in response to a change in environmental conditions in the monitored region.

Abstract: A surveillance system (10) for monitoring movement in a region of interest (18) is described. The surveillance system (10) includes: An image capturing system (12) having a field of view (16) including a region of interest (18), and adapted to capture an image of the region of interest (18). An image processing system (78) configured to process a time-sequential series of images of the field of view from the image capturing system such that at least a portion (52, 53, 54) of each processed image (50) is analyzed for detecting movement within the region of interest (18). The image capturing system (12) is configured to capture, in each image, different apparent magnifications of respective zones (20, 22, 24) within the region of interest (18) in the field of view (16) that are at different distances from the image capturing system (12) such that an object (60) in at least one position in at least two of said zones has substantially the same apparent size in the images.

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: 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 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: 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: 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: 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).