Abstract: The present invention provides apparatus and methods for safety compliance in hazardous situations. The apparatus may include sensing means for detecting a first protective apparatus, means for detecting a subject, monitoring means for monitoring engagement of the protective apparatus with the subject; and a controller for controlling operability of a second apparatus according to the monitoring means. Embodiments of the invention include the protective apparatus being eyewear or attenuating sound or radiation. The apparatus may include a power source. The communication between the elements of the apparatus may be by any suitable means, whether fixed line, radio frequency, optical transmission, acoustical, or the like.

Abstract: A method for the determination of the time of flight of a signal transmitted between a transmitter (42, 44) and a receiver (44, 42). In one form, the method involves transmitting a first signal and a second signal having a waveform modification introduced at a predetermined point in time of the duration of the second signal; receiving said first and second transmitted signals; determining a point of diversion between the first and second received signals to determine an arrival time of the introduced waveform feature modification at the receiver. In addition, the invention provides an accurate time of flight determination of ultrasonic signals in a flow sensor (24) adapted for a smoke detector system (10).

Abstract: A beam detector (10) including a light source (32), a receiver (34), and a target (36), acting in co-operation to detect particles in a monitored area (38). The target (36), reflects incident light (40), resulting in reflected light (32) being returned to receiver (34). The receiver (34) is a 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 (10) emits a first light beam (3614) in a first wavelength band; a second light beam (3618) in a second wavelength band; and a third light beam (3616) 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 method and apparatus for determining flow in an aspirated smoke detector system includes a plurality of sampling pipes in fluid communication with a smoke detector, a flow rate detector in at least one of the sampling pipes that senses a signal transmitted between a first and second signal transceiver, wherein the first transceiver transceives signals in at least two of the sampling pipes.

Abstract: A method of detecting particles in an air flow is described. The method includes receiving a signal indicative of light intensity scattered from the air flow at a plurality of wavelengths and processing the signal indicative of the intensity of received light at each of the wavelengths and a corresponding wavelength dependent parameter to generate an output signal indicative of at least one characteristic of particles in the air flow. A particle detection system is also described.

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.

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: The present invention relates to the field of pollution monitoring equipment and in particular to aspirated particle detector systems, which detect particles in air sampled from a number of locations. The present invention provides a method and apparatus for determining flow in an aspirated particle detector system, said system comprising a plurality of carriers in fluid communication with a particle detector, comprising means for detecting the flow rate in at least one of the carriers comprising sensing a signal transmitted between a first and a second signal transceiver (44a-d, 42) wherein the first transceiver (42) is adapted to transceive signals in at least two of the carriers. In a preferred embodiment, the invention relates to the use of an ultrasonic means of flow sensing within an aspirated smoke detector system.

Abstract: A method and apparatus for determining flow in an aspirated particle detector system, includes a plurality of carriers in fluid communication with a particle detector, a flow rate detector in at least one of the carriers that senses a signal transmitted between a first and a second signal transceiver, wherein the first transceiver transceives signals in at least two of the carriers.

Abstract: An apparatus for detecting particles in an airflow is disclosed. The apparatus can include at least one light source for illuminating a one or more portions of the airflow, at least one photo-detector positioned to detect light scattered from one or more illuminated volumes of the airflow. The at least one light source and at least one photo detector are arranged such that a signal indicative of light scattered from a plurality of illuminated volumes can be derived from the output of the at least one photo detector. The apparatus also includes a signal processing apparatus configured to process said signals indicative of light scattered from a plurality of illuminated volumes to determine whether particles have been detected in the airflow.

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 present invention relates to the field of pollution monitoring equipment and in particular to aspirated particle detector systems, which detect particles in air sampled from a number of locations The present invention provides a method and apparatus for determining flow in an aspirated particle detector systems said system comprising a plurality of carriers in fluid communication with a particle detector, comprising means for detecting the flow rate in at least one of the carriers comprising sensing a signal transmitted between a first and a second signal transceiver (44a-d, 42) wherein the first transceiver (42) is adapted to transceive signals in at least two of the carriers. In a preferred embodiment, the invention relates to the use of an ultrasonic means of flow sensing within an aspirated smoke detector system.

Abstract: The present invention relates to the field of sensing apparatus (10) in detecting particles in air sampled from a number of locations. In one aspect the present invention provides for the determination of the time of flight of a signal transmitted between a transmitter (42, 44) and a receiver (44, 42), comprising: transmitting a first signal comprising at least one characteristic waveform feature; transmitting a second signal comprising at least one characteristic waveform feature and a waveform modification introduced at a predetermined point in time of the duration of the second signal; receiving said first and second transmitted signals; determining a point of diversion between corresponding characteristic waveform features of the first and second received signals comprising super positioning said first and second received signals such that said point of diversion corresponds to an arrival time of the introduced waveform feature modification at the receiver.

Abstract: A calibration frame for a non-contact measurement system includes a frame structure (12); a plurality of targets (14) which may be light emitting diodes supported by the frame structure for viewing by the measurement system; control means for activating each of the targets for allowing the targets to be identified by the measurement system; memory means for storing data relating to the position of each target; and a communication link such as an infrared link for transferring data from the calibration frame to the measurement system which relates to the position of that target.