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FireVuFlame Detection

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History of Visual Smoke and Flame Detection

● NetVu Smoke and Flame detection developed since early 90’s.● Early solutions based on VSD / VFD developed in partnership with

Detector Technologies ( D-Tec ) ( Patented previously, now lapsed). ● In 2000’s evolved into SmokeVu and FireVu integrated with the NetVu

Connected recording and IP solutions.● In 2012 a completely new Smoke Detection algorithm was introduced,

which mitigated the vast majority of false alarms from movement and lighting changes.

● In 2013 a completely new Flame detection algorithm was developed, which relies on the precise measurement of the visible and near visible spectrum, setting it well beyond the capabilities of previous ‘flicker detection’ forms of flame detection. ( Patent Pending )

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Early Flame Detection

● Detection achieved by sensing flickering characteristic of the variation and guttering of a typical hydrocarbon flame.

● Such flames exhibit flicker at multiple frequency bands between 4Hz and 15Hz.

● Rely upon a correctly exposed visual image.● Susceptible to false alarms from sources such as flashing warning

beacons, and many other varying light sources, such as reflections on water and other materials, especially outdoors.

● May also respond falsely to PC screens and other displays.● Under low light conditions, quite likely that the flame source will in fact

just be perceived as a glowing ‘blob’ rather than exhibiting the flicker characteristics

● Often tested with a simple movie or a ‘fireplace screen saver’, even though there is no actual flame present.

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NetVu Flame Detection

● Utilises precise spectral measurements, and correlates to the physical laws of ‘Black Body Radiation

● Characteristic hydrocarbon flame colours result from the Black Body emissions of heated soot particles.

● The colour and intensity of these particles follow precise physical laws.

● Multiple controlled exposures determine if flame specific values occur across a wide range of temperatures giving specific colours and intensities in accordance with Planck’s Law.

● Multiple ‘hits’ across a defined period provides a very accurate determination of flames, regardless of lighting conditions, with very high rejection of false alarms.

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Flame Detection

● Above images show conventional AGC controlled exposure, and one of the fixed exposure images. Note complete rejection of external window in fixed exposure image showing flame. ● FireVu Flame Detectors run at 60 frames/sec; 30 frames normal visual range , 30 frames fixed exposure sequence.

● Video analytics and application of Planck’s law to fixed exposure frames gives very accurate and reliable flame detection

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Implementation

● Calibrated Fixed Iris and Focal length lens in 3.5mm, 6mm and 12mm format.

● Customized bandpass IR cut filter provides for analysis of near infrared as part of the measurement spectrum

● NetVu Connected streaming format supports multiple embedded meta data and embedded graphical diagnostic data.

● Both visual and sequence of constant exposure streams are recorded, complete with all exposure and analytic parameters and output.

● Enterprise Observer allows display and analysis of complete algorithm operation.

● Closed IP TV technology allows for secure deployment, with multipel firewalls, segregation and health check systems.

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Definition of Working Range

● Definition of Standard pan fire test as used in certification testing● A 1ft x 1ft oil pan, with between 600 - 700ml of fuel, typically diesel

fuel or N-Heptane.

● Detection to occur within 60 seconds of a fully developed flame.

● Nominal operating range based on detecting a standard ‘pan fire’ test at that distance. At this distance, horizontal Field of View is c. 20m.

● Larger flame sources can be detected at proportionately greater distance

● Smaller flame sources can be detected at closer distances.● At working distance, detection typically within 5-10 seconds of flame

being established, however detection can be achieved within limit time at up to twice that distance where there are no high intensity flashing light sources and maximum sensitivity selected by zone.

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Advantages of FireVu

● Long Range – Mid Range 6mm Model achieves Smoke and Flame Detection to 35m, Flame only detection at 50m and beyond. In independent testing, flame detected at 95m at maximum sensitivity settings.

● Models available for 20m ( 3.5mm), 35m ( 6mm), 70m ( 12mm) each give a nominal 20m wide field of view at the nominal range to provide high degree of flexibility in installation and coverage

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Advantages of FireVu

● False Alarm Rejection – Vastly superior false alarm than Visual flame detectors based upon general cameras and ‘flicker detection’ methods.

● High Sensitivity – Will detect flame sources as small as 1.5-2% of the horizontal and vertical field of view.

● Early Detection - Offering an early warning alarm, FireVu is able to detect the presence of flame and smoke at a fire’s inception stage, not needing to wait for the smoke to reach the detector. This provides the best opportunity to minimize commercial impacts, saving loss of/damage to costly equipment.

● Visual Verification - The presence, location and severity of the fire is able to be visually monitored and confirmed, providing detailed knowledge of potential threats.

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Advantages of FireVu

● Full Integration - Relay outputs and alarm inputs enable full integration with existing building management / fire panel systems enabling remote use of suppression systems

● Zones - Each channel can be segmented into 16 detection zones, each of which are customisable in terms of the sensitivity in detecting flame and smoke. This allows for sections where smoke, or smoke like phenomena are present normally to still be analysed, ignoring affected zones

● Flexibility - Because FireVu operates using a cameras field of view, specific, risky items or areas can be actively monitored. This may include deposits of flammable material or machinery where friction can cause overheating, enabling smoke within the risk area to be identified at its earliest possible stage

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Advantages of FireVu

● Real-time video stream● Draws attention to exactly what triggered the alarm and where in

the field of view it is through the use of coloured boxes.

● Lets you immediately know the size and scale of the fire so appropriate action can be taken. From allowing someone to tackle it with a fire extinguisher to immediately evacuating the building.

● Provides footage of the incident which will allow for post-event analysis to help determine the cause of the fire. This means processes can be improved and the site made safer in order to ensure there’s no repeat incident.

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Advantages of FireVu

● Remote Monitoring with both Video and Metadata● Supervision of both commissioning and on-going support and

maintenance of the system

● Fully automated Health Monitoring and logging solution can be operated either locally or as a ‘Cloud’ service.

● False positives can be analysed in detail using video and the data from the detectors. This allows parameters to be adjusted, reducing false positive levels and improving system performance.

● ‘Forensic’ analysis mode allows for replay of both false alarm sources and site tests to verify correct operation.

● Virtual NVR Infrastructure - provides benefits of advanced network security with simplified installation and maintenance.

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FireVu Multi Detector

● Built in Temperature Sensor Array● 80 x 62 Thermopiles array senses absolute temperature at 0.1

degC resolution.

● Verification of Flame source with Heat Detection

● Independent Heat/Hotspot Detection with a warning and alarm threshold configured in up to sixteen independent zones for process and materials monitoring.

● Available in 6mm format, giving nominal 35m working distance with 20m horizontal field of view.

● Accurate measurement of thermal target 0.5m x 0.5m at 20m horizontal field of view / working distance.

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FireVu Multi Detector

● Visual Image:

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FireVu Multi Detector

● Temperature Image:

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FireVu Multi Detector

● Overlay Image:

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FireVu Multi Detector

● Confirmed Visual & Temperature Detection:

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Alternate Technologies

● Aspirating smoke detectors and beam detectors can only be used indoors and struggle with large voluminous areas as they rely on smoke reaching the beam or pipes. Historically they have issues with dusty, dirty environments triggering false alarms or going into a trouble/fault state as filters become blocked, resulting in frequent extra maintenance

● Thermal imaging cameras are often expensive and unless accompanied by an additional CCTV image provide little or no situational awareness, preventing the end user or system operator from being able to identify the true nature of the risk and adopt the most appropriate course of action

● Triple IR detectors have a limited range, the greatest of which is listed at 65m. A complete lack of any visual output means that any alarm received cannot be verified. The technology is susceptible to false triggers as a result of direct sunlight, either if used externally or from reflections from floors near entrances when deployed internally