20 Dec Protecting people on the move
Mass transit applications are becoming an ever-increasing focus as we look to create the infrastructure to deal with the continuing growth in the world’s population. Here Kelvin Miller, Sales Director at industrial fire detection specialists Patol, considers the increasing role of thermal fire detection in protecting transportation applications.
Providing the means through which people are able to travel smoothly, both locally and globally, has never been more important. Ensuring a safe environment in airports, railways, ports and tunnels is a central requirement in this process, including the provision of effective fire safety and security measures.
In the past, thermal imaging was seen primarily as a specialty technology. As a consequence, a common misconception among fire and security integrators and end users is that thermal imaging is applicable in only a few very specialist environments. However, such thinking is now changing with systems based on infrared camera technology increasingly enhancing fire and security measures across many transportation projects, improving protection of people and property all over the world.
Adoption of thermal solutions at some level in transportation applications is growing at a much faster rate than previously. There is a greater appreciation of the benefits the technology offers in a wide range of transport environments in terms of both fire and security. An example is airports which are characterised by the need to monitor large areas, as well as having extensive perimeter fence lines that need tight security.
There is also a growing awareness from train operators and authorities of the need for active fire safety in railway vehicles and in underground railway tunnels. Fires in tunnels and vehicles can have a devastating impact on both people and infrastructure. In the worst cases they result in fatalities, material damage and significant disruption of important infrastructure lines. Effective fire prevention, detection and control saves lives, as well as reducing the costs of consequential damage and the potential and sometimes severe ongoing effects in terms of business continuity.
For airports, the importance of providing 24/7 surveillance and monitoring of all perimeters is crucial to maintaining effective security. It is imperative that no threat goes undetected. Traditional CCTV cameras are still widely used for airport perimeter protection but require light to display a decent image. In addition, many of these cameras are susceptible to higher false alarm rates, despite advances in video analytic software.
Due to some of the limitations of conventional CCTV, thermal cameras are becoming an increasingly popular option for airport protection, both inside and outside the perimeter. Infrared camera based systems can provide 24/7 coverage of the airport perimeter, regardless of light levels or weather conditions. These cameras can operate in any light as they are sensitive to heat rather than light. Any heat signatures emitted by vehicles, equipment, infrastructure, individuals, animals or aircraft is easily picked up and the moment an anomaly is spotted, the appropriate response teams can be notified.
Nowadays, a thermal camera system can provide matchless image quality, a higher processing capability, better range and a reduction in false alarms due to improvements in algorithms. Thermal cameras can be also integrated with additional sensors such as radar systems to provide an extra layer of perimeter protection.
In some applications perimeter protection can be further enhanced by combining fixed shorter range cameras with longer range PTZ (pan/tilt/zoom) camera systems that can provide 360-degree coverage within a few kilometres of the perimeter. Pan and tilt thermal cameras are ideal for this application, with a thermal camera for 24/7 detection and the visible-light camera for colour images and visual evidence. These technologies, along with the alarm management, PTZ control and security functions controlled by the software, enable the airport to perform a more information-rich, intelligent assessment with maximum flexibility.
A further advantage is that thermal cameras deployed in a well-designed installation can provide cost savings. Their superior detection range allows the deployment of fewer thermal cameras along a perimeter compared to the visible light cameras required for the same coverage. This saves both time and resources for both end user and integrator.
Railway tracks and yards
Railway security applications are designed to ensure both passenger and load safety. In this case, safety monitoring and object detection by thermal cameras on (or near) railway tracks can help prevent collisions by detecting vehicles that are stuck on a level crossing and blocking the passage of an approaching train. Also, they can help identify crossing pedestrians or detect people falling from a platform or walking on railway tracks. Importantly, this is without triggering false alarms by filtering out objects such as animals or passing trains.
As technology evolves, maintenance teams are increasing their investment in predictive and preventative maintenance strategies to deliver better, more reliable rail networks. Thermal imaging camera-based systems, along with event control software, offers such teams a set of diagnostic tools to monitor and compare key operating parameters and ensure that they are within a normal or expected range.
From unexpected events to failed railway infrastructure, it can be extremely beneficial to have the capability to see well ahead of moving trains. Dual channel thermal and colour day cameras can identify issues on the tracks several kilometres ahead of trains in any weather conditions. In the case of cooled thermal cameras, they can even provide rail safety detection capabilities beyond 20km.
This kind of full coverage offers visibility of any disturbances on the tracks. Constant coverage ensures that control room operators will be able to stop trains well ahead of animals, people, vehicles or other obstructions in the crossing area.
Also, advanced cooled optics on board trains allow for detection of the smallest details, improving response capabilities. The cameras allow operators sufficient time to stop the train if needed, drastically reducing instances of crashes and impacts.
Rail infrastructure maintenance
Railway infrastructure is at particular threat from constant usage. Thermal cameras help to prevent incidents caused by infrastructure failure through their ability to generate information regarding the conditions of wheel bearings or axle bearings, for example, to extend the operational life of rolling stock. They can also measure spatial variations in rail-track temperatures to avoid track buckling, as well as detecting hotspots in overhead catenaries and inspecting pantographs on electrified rolling stock.
Bridge and tunnel security
A major benefit of thermal cameras is that they enable timely detection and therefore intervention in important events. High risk areas like bridges and tunnels can be constantly monitored for fires. Early fire detection systems using infrared cameras can measure the temperature of any object in its field of view, allowing detection of fire at an early stage, long before traditional fire detection systems.
By supplementing an existing maintenance programme with the use of thermal imaging, rail network operators can extend the operational life of their infrastructure, reduce the operational lifecycle costs of their assets and offer full visibility and situational awareness of any disturbances in depots, on the tracks, and around critical railway infrastructure.
The safety and security of seaports is heavily dependent on situational awareness. Ports present unique security and safety issues that must be anticipated and addressed. From miles of unguarded, unlit perimeters to ever-changing lighting and weather conditions and a huge influx of commercial trade vessels, traditional video security finds it difficult to provide the comprehensive intelligence demanded by such a high-security facility.
By deploying long-range thermal pan-tilt cameras on high masts and piers, staff can observe water vessels both near and far. Also, thermal technology aids coastguards on search-and rescue missions by allowing them to assess swimmers and recreational boats that may be in distress. They are particularly useful at night or on days with rain or light fog. Thermal cameras can also be employed to monitor the physical and virtual perimeters of ports, identifying and assessing unauthorised personnel. Thermal zoom lenses, a recent technology advance for uncooled cameras, provides enhanced monitoring capabilities.
Roads, bridges and tunnels.
Municipalities use thermal cameras to provide 24/7 observation of critical transportation infrastructure, such as roads, highways, bridges and tunnels. When it comes to roadway monitoring, thermal cameras are not adversely affected by glare from car headlights. As such, they allow staff to clearly see vehicles, analyse traffic patterns and assess the cause of traffic disruptions, thereby reducing congestion and potentially speeding the dispatch of roadside assistance or maintenance crews. Fixed thermal cameras deployed for the detection and counting of cars at stop lights offer a cost-effective alternative to ground sensors which require groundwork preparation, often involving the breaking up of pavements.
Thermal imaging also improves coverage of key areas around bridges and tunnels to detect unauthorised entries, monitor unusual activity and detect hot spots that have the potential to turn into full blown fires.
Flexibility across transportation applications
Every day passengers rely on planes, trains, metros or trams to take them safely and quickly to their destination. However, accidents caused by fire or by careless behaviour can lead to delays, as well as severe damage to transport infrastructure or to people. Thermal imaging cameras can detect many of these incidents in time, thanks to the 24/7 monitoring process, and help public transportation operators take the appropriate measures quickly.
In addition, early fire detection systems using thermal cameras can help to prevent fires in any transport environment by detecting hot-spots or by detecting fires at an early stage to allow prompt intervention and prevent them turning into potentially major conflagrations. Thermal cameras can be configured to generate a direct alarm output to a control room operator when user-defined maximum temperature thresholds are exceeded.
These thermographic systems are particularly effective in low-light or no-light environments. Visible cameras rely on reflected light to create images and show contrast, which is difficult at night, particularly in remote areas. This is not the case with thermal cameras which capture video of people or objects in the darkest of night time conditions. Thermal imaging cameras can therefore enable transport operators to detect trespassers, stopped cars on tracks, people falling from platforms on tracks, people walking in tunnels, etc 24 hours a day.
From speciality to mainstream
There has been a definite shift in the perception of thermal imaging. From a technology that was originally deemed to be only relevant in very specific applications, it is now much more widely adopted, with transportation being very much a growth market. It is a technology which offers a number of advantages, not least the capacity for full visibility and situational awareness of any disturbances in any transport infrastructure. Networked systems, coupled with a range of different tracking and alerting analytics available within the thermal cameras, provide control room operators with the critical information needed to keep trains, planes or boats running on schedule. Furthermore, they protect assets and facilities while keeping dangerous areas constantly monitored, allowing for rapid response to possible risks. With the development of infrastructure showing no signs of slowing as the needs of a growing population continue to evolve, finding ways of ensuring that infrastructure is safe will only increase. Thermal imaging, with its many advantages, will have an important role to play in that process.
Alongside its own UK manufactured range of fire detection systems, Patol is also the UK partner for a number of other manufacturers, including VisionTIR, the Spanish producer of the FireTIR system based on infrared cameras for early fire detection and temperature monitoring.