Video smoke detection (VSD) provides the security and fire safety industry with a new and efficient way to detect smoke and fire in a very early stage, writes Pieter Claerhout CEO of product company Araani.
VSD makes use of CCTV cameras and smart video analytics that are able to recognise initiating smoke and fire in the video image. VSD is especially used in critical infrastructure, to protect people, property and production processes. VSD can prevent serious fires from happening and thus avoid costs, including the cost of damage, of human lives and of production stops during an alarm.
Conventional smoke detection
In certain types of critical environments, like chemical plants, waste storage bunkers or production facilities, the impact and the risk of a fire can be very high. That’s why companies operating in such environments need to take the appropriate fire safety measures. However, it is exactly in those environments that conventional smoke detection technologies, like beam or point-type detectors, will fall short.
First of all, conventional smoke detection systems, like point, beam or aspiration-based smoke detectors, need to make contact with the smoke before they can generate an actual alarm. But in the typical high buildings of chemical plants, production halls or storage rooms, the smoke from an initiating fire will reach the smoke detector very slowly, too late or not all, because of a process called stratification, which stops the upward movement of smoke.
A second difficulty with conventional smoke detectors is that they can be set off unintentionally by chemicals, dust, exhaust gases or vapor, creating a high volume of unwanted alarms. Dust is also one of the reasons why a conventional smoke detector will degrade very fast, which will impact its detection performance. Video Smoke Detection is an addition to the spectrum of smoke detection technologies, that is specifically useful for environments where no adequate solution is available today:
– High-impact/high-risk facilities;
– Harsh environments; and
– Indoor spaces with high ceilings.
How does VSD work?
Today’s video smoke detection systems rely on the resolution and accuracy of a standard network security camera. Carefully developed software algorithms installed on the camera scan the environment and continuously analyse it in real time to locate the fire incident. In case of an event, an alarm output is sent over to the fire control panel. A video detection system can be connected to a video management system to provide control room operators with 24/7 situational awareness.
This approach has a number of advantages. Video smoke detection systems will see initiating smoke much faster than conventional systems. VSD makes efficient use of CCTV, so it is able to see dangers at source, from a very large distance. Unlike many other smoke detection technologies, video analytics do not need to make physical contact with smoke or dust. They immediately ‘see’ the danger when and where it originates.
VSD is also very accurate and thus the false alarm rate will be extremely low. Unwanted alarms can be very costly. Just think of the time lost when a production line needs to be stopped or imagine the cost of an erroneously called emergency team. Video smoke detection systems on the other hand will efficiently analyze the video image to make a distinction between starting smoke and other irregularities, such as people walking in the field of view, animals, vehicles or objects.
Control room operators can monitor the CCTV video images in real time. This allows them to assess the nature and severity of the fire as well as the stage it is in. Based on pre-incident recording, they can see whether people are present at the place of the incident and they can better assess the overall situation. This way, they can also make better use of their emergency resources.
When to use
VSD will especially prove its value where contact-based smoke detection systems are not efficient, including high-impact environments, harsh environments, and buildings with great height. In some environments, such as chemical plants, even a small fire can cause huge consequential damage. In these high-risk environments, conventional smoke detectors would be useless, because they might only get activated when the damage is already done. VSD on the other hand is so fast that it will efficiently reduce the impact and the risk of a fire outbreak.
Video smoke detection is also ideal for use in tall buildings or large indoor spaces. High or voluminous buildings of 10m+ have issues with the stratification of smoke whereby smoke will not rise high enough or quickly enough to reach ceiling mounted point or beam detectors. This is the case for example in aircraft hangars, airport passenger terminals, factory production halls, retail areas, museums and many historical buildings.
In production facilities, alarms will require the production lines to be stopped. In harsh environments, where chemicals, dust or vapor are present every day, such as chemical plants, waste recycling plants, wood processing companies or in the oil and gas industry, conventional smoke detectors will generate a lot of false alarms. But, because of its visual nature, video smoke detection will be able to analyze the above-mentioned phenomena in a more intelligent way through the use of smart video analytics. This will heavily reduce the number of false alarms.
Customised sensitivity
Smoke detection systems usually have the possibility to lower the detection sensitivity during specific time slots during extreme activities that otherwise would generate unwanted alarms. These conditions could include the start-up of the waste management process or the cleaning of the waste shredder.
Self-learning video detection systems are intelligent enough to filter out unwanted events, such as exhaust gases of loaders, moving dust or waste heaps. As such, they are perfectly able to adapt their sensitivity autonomously, without actually adhering to fixed time slots. For example, in periods of heavy activity from loaders or a shredder, the detected activity will enable the smoke detection sensitivity to be decreased. Conversely, when the VSD system detects no activity, for example at night, during weekends or in the holiday season, the system will adjust to a higher degree of sensitivity.
Detection at the source
Video smoke detection has a number of benefits that conventional technologies lack: detection speed, accuracy, robustness and visual operator feedback. This makes it the ultimate detection technology for critical environments that want to reduce the risk and impact of a fire 24/7. Because of its visual nature, VSD can spot initiating fires at the source, practically from any distance. This is a huge speed advantage compared to smoke detection technologies that need to make physical contact with the smoke. With VSD, there is no need to wait until the smoke has reached the ceiling. This is time gained for anyone who needs to make tough decisions about the required actions that need to be taken to avoid further fire and smoke damage.
A detection system that generates too many unwanted alarms will become useless and ignored in the long run. Video Smoke Detection on the other hand can effectively filter out unwanted events that are so typical of critical environments.
Enabling better decisions
Unwanted alarm or not, probably the biggest advantage of Video Smoke Detection technology is that it gives the operator time for more interpretation. Since it is so fast and since it allows for visual verification, VSD provides the operator with valuable time to make a well-founded decision. That decision could be calling the emergency services and avoid further damage or human suffering. But bearing in mind the cost of an alarm, it could also be ignoring the alarm and if possible isolating and controlling the fire to prevent the entire operation from closing.
About the author
Pieter Claerhout is CEO of Araani, a Belgian company that specialies in video analytics. Araani is the developer of SmokeCatcher, the company’s video smoke detection product. Visit www.araani.com.
