Detailed Risk Analysis
Container surveillance in hazardous areas
Incorrect storage of hazardous chemical substances and inadequate surveillance of storage areas all too often result in catastrophic industrial accidents. In June 2020 a container with toxic chemicals exploded in a chemical factory in India, resulting in a catastrophe that claimed the lives of eight workers, with a further 74 sustaining injuries, some of them life-changing. Fire fighters needed five hours to get the fire under control. Only two months later, this terrible accident was overshadowed by the events in Beirut. An explosion of ammonium nitrate containers devastated large areas of the Lebanese capital. 220 people died as a result, and many more were injured.
Since the uncontrolled interaction of hazardous substances, oxygen, heat or sparks poses an extremely high risk for life and assets, the storage and monitoring of dangerous substances in hazardous areas is one of the most important tasks of plant operators. Particular caution is required if hazardous substances are stored in containers. Container fires are notoriously difficult to fight, because there are usually large amounts stored and access is difficult. What is more, in many cases there is an increased risk of subsequent fires or multiple explosions. For such incidents, fire brigades not only have to work at full capacity, employing large numbers of staff on the callout, but they also need specific expertise in fighting chemical fires. Consequently, fire brigades across the world are highly sensitized to callouts to chemical environments - even if they involve a large number of false alarms.
CCTV systems from R. STAHL
As a leading manufacturer of explosion-protected switchgear, surveillance systems and network components, R. STAHL has been involved in this issue for many years. For the surveillance of containers, tanks, piping and other potential sources of fire, the Ex protection specialist develops customized CCTV systems that can be flexibly adapted to suit different parameters and local conditions. For this, the one-stop-supplier provides hardware as well as services that are key to setting up a state-of-the-art, secure video surveillance system: from concept and project engineering to documentation, user training, factory and site acceptance tests (FAT / SAT) as well as commissioning of the surveillance systems.
Identify risks, prevent false alarms
To ensure a reliable detection of a hazard source when monitoring containers in hazardous areas and simultaneously prevent costly false alarms, R. STAHL's explosion-protected IP thermal imaging cameras now also feature separate detection of flame movement and temperature. This function means that the intelligent cameras can clearly distinguish whether there is "only" a flame movement or whether the temperature has also risen above the pre-defined limit. Since surveillance systems to date have not featured this functionality, fire brigades had to attend in every case to assess the seriousness of the situation on site.
The measuring module integrated into the series EC-840S-TIC cameras from R. STAHL distinguishes temperatures in the video recording pixel by pixel. Only once the pre-defined temperature levels are exceeded the programmed alarm procedure is triggered. These reliable fire and warning alarms increase surveillance security in hazardous areas, whilst greatly reducing false alarms and their associated cost. Furthermore, CCTV systems with thermal imaging cameras can monitor large areas with corresponding thermal images: depending on the type of thermal imaging camera, areas of a size of up to 650 m² can be monitored in great detail.
An integrated concept is the key
Even the latest thermal imaging cameras cannot ensure sufficient fire protection if used by themselves. Only the combination of explosion-protected cameras, industrial cameras where needed and associated software can ensure a sufficient level of protection. In chemical and pharmaceutical companies, for example, piping, transport routes and loading/unloading stations are monitored with fast-panning PTZ cameras (pan/tilt/zoom) from R. STAHL. These versions cover all surveillance points programmed in a virtual guard tour, and they can precisely zoom in on selected spots within 0.2 seconds. If the virtual guard tours also cover areas that should remain hidden, these can be blacked out with the "Dynamic Masking" function. Because this blacking out is dynamic, the specified areas will remain blacked out regardless of the panning and focusing motions of the camera. Because of their large range of functions, including precise 360° panning, fast and precise focusing and the high-quality images with electronic image stabilization, PTZ cameras are today used in many different applications.
Looking around corners
Chemical or pharmaceutical plants have many secluded areas that are difficult to view from afar. For such cases, AFZ (autofocus/zoom) cameras are particularly suitable for indoor monitoring. To cover the entire premises including zones blocked from direct view, we recommend positioning several cameras so that they provide seamless coverage, with each camera taking on part of the view and the combination of all cameras providing a complete overall view of the locality. Like many of R. STAHL's cameras, the AFZ models have been designed for temperatures ranging from -55 °C to +65 °C for continuous, 24/7 surveillance even under extreme conditions. The cameras, certified for operation almost everywhere across the world, not only can resist considerable temperature fluctuations, but also salt spray and vibrations.
Inside view: sight-glass cameras from R. STAHL
For monitoring tanks and reactors through sight glasses, the manufacturer offers specific sight-glass cameras that can be positioned exactly on top of the sight glass and provide clear, bright images of all processes inside due to their high degree of light sensitivity. If a process suddenly generates foaming, the direct image transfer to the control room allows for a much faster intervention by staff than would be possible with inspection rounds.
All-seeing eye for outdoor areas
For wide-reaching, 360° control of hazardous outdoor areas and complete plant sections R. STAHL has developed the EC-750 Dome camera. Its dust-proof and submersible stainless-steel enclosure with degree of protection IP68 is suitable for operation in rough ambient conditions. Located under a transparent dome, the pan and tilt camera with 18x or 40x optical zoom can also provide close-ups and enlargements of conspicuous or dangerous locations. Also, unauthorized personnel or wrongly placed goods can immediately be spotted for prompt intervention.
All information is pooled by a video management software such as CAYUGA, whose wide range of functions make it a key part of any highly professional surveillance solutions. The modular, upgradeable software solution can map all industry-specific complexities. Powerful alarm management concepts are part of the standard, as well as easy-to-use video players, configuration assistants and an analytics interface for integrating other analysis software. In addition, third-party systems for physical security information management, access control as well as break-in and fire alarms can also be integrated.
One-Stop-Supplier R. STAHL – everything from one source
As one-stop supplier, R. STAHL accompanies the set-up of a CCTV system right from the start, carrying out personal site inspections where required for a customized CCTV system - to prevent fires and explosions, thus ensuring the safety of personnel, equipment and plants.